Release 0.3.3.

Add CSS `scroll-margin-top` to headings which contain link targets.

.gitattributes

@@ -2,7 +2,7 @@
 
 * text=auto eol=lf
 *.rs rust
-*.woff -text
-*.ttf -text
-*.otf -text
-*.png -text
+*.woff binary
+*.ttf binary
+*.otf binary
+*.png binary

.github/workflows/deploy.yml

@@ -0,0 +1,45 @@
+name: Deploy
+on:
+  release:
+    types: [created]
+
+jobs:
+  release:
+    name: Deploy Release
+    runs-on: ${{ matrix.os }}
+    strategy:
+      matrix:
+        os: [ubuntu-latest, macos-latest, windows-latest]
+    steps:
+    - uses: actions/checkout@master
+    - name: Install hub
+      run: ci/install-hub.sh ${{ matrix.os }}
+      shell: bash
+    - name: Install Rustup
+      run: ci/install-rustup.sh stable
+      shell: bash
+    - name: Install Rust
+      run: ci/install-rust.sh stable
+      shell: bash
+    - name: Build and deploy artifacts
+      env:
+        GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+      run: ci/make-release.sh ${{ matrix.os }}
+      shell: bash
+  pages:
+    name: GitHub Pages
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@master
+    - name: Install Rust (rustup)
+      run: rustup update stable --no-self-update && rustup default stable
+    - name: Build book
+      run: cargo run -- build book-example
+    - name: Deploy to GitHub
+      env:
+        GITHUB_DEPLOY_KEY: ${{ secrets.GITHUB_DEPLOY_KEY }}
+      run: |
+        touch book-example/book/.nojekyll
+        curl -LsSf https://raw.githubusercontent.com/rust-lang/simpleinfra/master/setup-deploy-keys/src/deploy.rs | rustc - -o /tmp/deploy
+        cd book-example/book
+        /tmp/deploy

.github/workflows/main.yml

@@ -0,0 +1,53 @@
+name: CI
+on:
+  # Only run when merging to master, or open/synchronize/reopen a PR.
+  push:
+    branches:
+      - master
+  pull_request:
+
+jobs:
+  test:
+    name: Test
+    runs-on: ${{ matrix.os }}
+    strategy:
+      matrix:
+        build: [stable, beta, nightly, macos, windows, msrv]
+        include:
+          - build: stable
+            os: ubuntu-latest
+            rust: stable
+          - build: beta
+            os: ubuntu-latest
+            rust: beta
+          - build: nightly
+            os: ubuntu-latest
+            rust: nightly
+          - build: macos
+            os: macos-latest
+            rust: stable
+          - build: windows
+            os: windows-latest
+            rust: stable
+          - build: msrv
+            os: ubuntu-latest
+            rust: 1.35.0
+    steps:
+    - uses: actions/checkout@master
+    - name: Install Rustup
+      run: bash ci/install-rustup.sh ${{ matrix.rust }}
+    - name: Install Rust
+      run: bash ci/install-rust.sh ${{ matrix.rust }}
+    - name: Build and run tests
+      run: cargo test
+    - name: Test no default
+      run: cargo test --no-default-features
+
+  rustfmt:
+    name: Rustfmt
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@master
+    - name: Install Rust
+      run: rustup update stable && rustup default stable && rustup component add rustfmt
+    - run: cargo fmt -- --check

.gitignore

@@ -9,3 +9,5 @@ book-example/book
 .vscode
 tests/dummy_book/book/
 
+# Ignore Jetbrains specific files.
+.idea/

.travis.yml

@@ -1,47 +0,0 @@
-language: rust
-
-cache: 
-  - cargo
-
-before_cache:
-  - chmod -R a+r $HOME/.cargo
-
-env:
-  global:
-    - CRATE_NAME=mdbook
-    - TARGET=x86_64-unknown-linux-gnu
-
-install:
-  - sh ci/install.sh
-  - export PATH=$PATH:$HOME/.cargo/bin
-
-script:
-  - cargo build --all --no-default-features
-  - cargo build --verbose
-  - cargo test --verbose
-
-after_success:
-  - bash ci/github_pages.sh
-
-before_deploy:
-  - sh ci/before_deploy.sh
-
-deploy:
-  provider: releases
-  api_key:
-    - secure: cURRWBr034iqBz/ifD7uOunBfNR30YxIXfgLX0osWz+iafkVbhDGYYz9sBmRraqO2P7L2koEXMADVb/md1kI2+ykiq/ml+l9zuEAZPVmvSGUN7ZD+7s+lu3l5OBPG5z175T+b2q2q2m8XVR7TW20ra4QbE0bq06KAoOyjSgQVBTSCYsL9uTsGwiVRMEqqJT/BmKhKJNkpGsTKyBSKkOXvfeAAbE260vXUDEN9TYdJ3fvteRrpwLX56ee64gIZUq0RjDc4SKIEqilM6iUtNMvurqaewYNGkiXKRruV6BPCHxEHo6NNT46kOJLBJTf7gZw//dWhSoWpg9P0gdAnPWm407kSa3F7aJ1eRShAFQ4BLyfz9efTqm+jP3fOp7Mm7igSh9w6caSRuOnSsUf5+raRQ8E5Y9HsWGzzpZQk24Fx9EGZ04EeDSdpZAFz+jcbMpHf8t2p4CEx0CCNwYvKx6EydMKbMF5QteQ8SQkXNLhv7Rz2OgtXWYZPRVCMfQfOplsi2InsLCrQxTgwh+6u654SqVSgaHG+IncEAxBrdWy4rHcg7qereUcKfcY3k96vaDxdn/T2c00Ig0aNFR91YnixGMd6J6tQgDcRK9jh6fUm1CCBE9hT+pNUmtgYKuWBoLZexUZFFnfuBed0WciBot1bGDDamndqKq0jJiAzg+GMHk=
-  file_glob: true
-  file: "$CRATE_NAME-$TRAVIS_TAG-$TARGET.*"
-  on:
-    condition: "$TRAVIS_RUST_VERSION = stable"
-    tags: true
-  skip_cleanup: true
-
-branches:
-  only:
-    - "/^v\\d+\\.\\d+\\.\\d+.*$/"
-    - master
-
-notifications:
-  email:
-    on_success: never

CHANGELOG.md

@@ -0,0 +1,299 @@
+# Changelog
+
+## mdBook 0.3.3
+[2b649fe...e5f77aa](https://github.com/rust-lang-nursery/mdBook/compare/2b649fe...e5f77aa)
+
+### Changed
+- Improvements to the automatic dark theme selection.
+  [#1069](https://github.com/rust-lang-nursery/mdBook/pull/1069)
+- Fragment links now prevent scrolling the header behind the menu bar.
+  [#1077](https://github.com/rust-lang-nursery/mdBook/pull/1077)
+
+### Fixed
+- Fixed error when building a book that has a spacer immediately after the
+  first chapter.
+  [#1075](https://github.com/rust-lang-nursery/mdBook/pull/1075)
+
+## mdBook 0.3.2
+[9cd47eb...2b649fe](https://github.com/rust-lang-nursery/mdBook/compare/9cd47eb...2b649fe)
+
+### Added
+- Added a markdown renderer, which is off by default. This may be useful for
+  debugging preprocessors.
+  [#1018](https://github.com/rust-lang-nursery/mdBook/pull/1018)
+- Code samples may now include line numbers with the
+  `output.html.playpen.line-numbers` configuration value.
+  [#1035](https://github.com/rust-lang-nursery/mdBook/pull/1035)
+- The `watch` and `serve` commands will now ignore files listed in
+  `.gitignore`.
+  [#1044](https://github.com/rust-lang-nursery/mdBook/pull/1044)
+- Added automatic dark-theme detection based on the CSS `prefers-color-scheme`
+  feature. This may be enabled by setting `output.html.preferred-dark-theme`
+  to your preferred dark theme.
+  [#1037](https://github.com/rust-lang-nursery/mdBook/pull/1037)
+- Added `rustdoc_include` preprocessor. This makes it easier to include
+  portions of an external Rust source file. The rest of the file is hidden,
+  but the user may expand it to see the entire file, and will continue to work
+  with `mdbook test`.
+  [#1003](https://github.com/rust-lang-nursery/mdBook/pull/1003)
+- Added Ctrl-Enter shortcut to the playpen editor to automatically run the
+  sample.
+  [#1066](https://github.com/rust-lang-nursery/mdBook/pull/1066)
+- Added `output.html.playpen.copyable` configuration option to disable
+  the copy button.
+  [#1050](https://github.com/rust-lang-nursery/mdBook/pull/1050)
+- Added ability to dynamically expand and fold sections within the sidebar.
+  See the `output.html.fold` configuration to enable this feature.
+  [#1027](https://github.com/rust-lang-nursery/mdBook/pull/1027)
+
+### Changed
+- Use standard `scrollbar-color` CSS along with webkit extension
+  [#816](https://github.com/rust-lang-nursery/mdBook/pull/816)
+- The renderer build directory is no longer deleted before the renderer is
+  run. This allows a backend to cache results between runs.
+  [#985](https://github.com/rust-lang-nursery/mdBook/pull/985)
+- Next/prev links now highlight on hover to indicate it is clickable.
+  [#994](https://github.com/rust-lang-nursery/mdBook/pull/994)
+- Increase padding of table headers.
+  [#824](https://github.com/rust-lang-nursery/mdBook/pull/824)
+- Errors in `[output.html]` config are no longer ignored.
+  [#1033](https://github.com/rust-lang-nursery/mdBook/pull/1033)
+- Updated highlight.js for syntax highlighting updates (primarily to add
+  async/await to Rust highlighting).
+  [#1041](https://github.com/rust-lang-nursery/mdBook/pull/1041)
+- Raised minimum supported rust version to 1.35.
+  [#1003](https://github.com/rust-lang-nursery/mdBook/pull/1003)
+- Hidden code lines are no longer dynamically removed via JavaScript, but
+  instead managed with CSS.
+  [#846](https://github.com/rust-lang-nursery/mdBook/pull/846)
+  [#1065](https://github.com/rust-lang-nursery/mdBook/pull/1065)
+- Changed the default font set for the ACE editor, giving preference to
+  "Source Code Pro".
+  [#1062](https://github.com/rust-lang-nursery/mdBook/pull/1062)
+- Windows 32-bit releases are no longer published.
+  [#1071](https://github.com/rust-lang-nursery/mdBook/pull/1071)
+
+### Fixed
+- Fixed sidebar auto-scrolling.
+  [#1052](https://github.com/rust-lang-nursery/mdBook/pull/1052)
+- Fixed error message when running `clean` multiple times.
+  [#1055](https://github.com/rust-lang-nursery/mdBook/pull/1055)
+- Actually fix the "next" link on index.html. The previous fix didn't work.
+  [#1005](https://github.com/rust-lang-nursery/mdBook/pull/1005)
+- Stop using `inline-block` for `inline code`, fixing selection highlighting
+  and some rendering issues.
+  [#1058](https://github.com/rust-lang-nursery/mdBook/pull/1058)
+- Fix header auto-hide on browsers with momentum scrolling that allows
+  negative `scrollTop`.
+  [#1070](https://github.com/rust-lang-nursery/mdBook/pull/1070)
+
+## mdBook 0.3.1
+[69a08ef...9cd47eb](https://github.com/rust-lang-nursery/mdBook/compare/69a08ef...9cd47eb)
+
+### Added
+- 🔥 Added ability to include files using anchor points instead of line numbers.
+  [#851](https://github.com/rust-lang-nursery/mdBook/pull/851)
+- Added `language` configuration value to set the language of the book, which
+  will affect things like the `<html lang="en">` tag.
+  [#941](https://github.com/rust-lang-nursery/mdBook/pull/941)
+
+### Changed
+- Updated to handlebars 2.0.
+  [#977](https://github.com/rust-lang-nursery/mdBook/pull/977)
+
+### Fixed
+- Fixed memory leak warning.
+  [#967](https://github.com/rust-lang-nursery/mdBook/pull/967)
+- Fix more print.html links.
+  [#963](https://github.com/rust-lang-nursery/mdBook/pull/963)
+- Fixed crash on some unicode input.
+  [#978](https://github.com/rust-lang-nursery/mdBook/pull/978)
+
+## mdBook 0.3.0
+[6cbc41d...69a08ef](https://github.com/rust-lang-nursery/mdBook/compare/6cbc41d...69a08ef)
+
+### Added
+- Added ability to resize the sidebar.
+  [#849](https://github.com/rust-lang-nursery/mdBook/pull/849)
+- Added `load_with_config_and_summary` function to `MDBook` to be able to
+  build a book with a custom `Summary`.
+  [#883](https://github.com/rust-lang-nursery/mdBook/pull/883)
+- Set `noindex` on `print.html` page to prevent robots from indexing it.
+  [#844](https://github.com/rust-lang-nursery/mdBook/pull/844)
+- Added support for ~~strikethrough~~ and GitHub-style tasklists.
+  [#952](https://github.com/rust-lang-nursery/mdBook/pull/952)
+
+### Changed
+- Command-line help output is now colored.
+  [#861](https://github.com/rust-lang-nursery/mdBook/pull/861)
+- The build directory is now deleted before rendering starts, instead of after
+  if finishes.
+  [#878](https://github.com/rust-lang-nursery/mdBook/pull/878)
+- Removed dependency on `same-file` crate.
+  [#903](https://github.com/rust-lang-nursery/mdBook/pull/903)
+- 💥 Renamed `with_preprecessor` to `with_preprocessor`.
+  [#906](https://github.com/rust-lang-nursery/mdBook/pull/906)
+- Updated ACE editor to 1.4.4, should remove a JavaScript console warning.
+  [#935](https://github.com/rust-lang-nursery/mdBook/pull/935)
+- Dependencies have been updated.
+  [#934](https://github.com/rust-lang-nursery/mdBook/pull/934)
+  [#945](https://github.com/rust-lang-nursery/mdBook/pull/945)
+- Highlight.js has been updated. This fixes some TOML highlighting, and adds
+  Julia support.
+  [#942](https://github.com/rust-lang-nursery/mdBook/pull/942)
+- 🔥 Updated to pulldown-cmark 0.5. This may have significant changes to the
+  formatting of existing books, as the newer version has more accurate
+  interpretation of the CommonMark spec and a large number of bug fixes and
+  changes.
+  [#898](https://github.com/rust-lang-nursery/mdBook/pull/898)
+- The `diff` language should now highlight correctly.
+  [#943](https://github.com/rust-lang-nursery/mdBook/pull/943)
+- Make the blank region of a header not clickable.
+  [#948](https://github.com/rust-lang-nursery/mdBook/pull/948)
+- Rustdoc tests now use the preprocessed content instead of the raw,
+  unpreprocessed content.
+  [#891](https://github.com/rust-lang-nursery/mdBook/pull/891)
+
+### Fixed
+- Fixed file change detection so that `mdbook serve` only reloads once when
+  multiple files are changed at once.
+  [#870](https://github.com/rust-lang-nursery/mdBook/pull/870)
+- Fixed on-hover color highlighting for links in sidebar.
+  [#834](https://github.com/rust-lang-nursery/mdBook/pull/834)
+- Fixed loss of focus when clicking the "Copy" button in code blocks.
+  [#867](https://github.com/rust-lang-nursery/mdBook/pull/867)
+- Fixed incorrectly stripping the path for `additional-js` files.
+  [#796](https://github.com/rust-lang-nursery/mdBook/pull/796)
+- Fixed color of `code spans` that are links.
+  [#905](https://github.com/rust-lang-nursery/mdBook/pull/905)
+- Fixed "next" navigation on index.html.
+  [#916](https://github.com/rust-lang-nursery/mdBook/pull/916)
+- Fixed keyboard chapter navigation for `file` urls.
+  [#915](https://github.com/rust-lang-nursery/mdBook/pull/915)
+- Fixed bad wrapping for inline code on some browsers.
+  [#818](https://github.com/rust-lang-nursery/mdBook/pull/818)
+- Properly load an existing `SUMMARY.md` in `mdbook init`.
+  [#841](https://github.com/rust-lang-nursery/mdBook/pull/841)
+- Fixed some broken links in `print.html`.
+  [#871](https://github.com/rust-lang-nursery/mdBook/pull/871)
+- The Rust Playground link now supports the 2018 edition.
+  [#946](https://github.com/rust-lang-nursery/mdBook/pull/946)
+
+## mdBook 0.2.3 (2018-01-18)
+[2c20c99...6cbc41d](https://github.com/rust-lang-nursery/mdBook/compare/2c20c99...6cbc41d)
+
+### Added
+- Added an optional button to the top of the page which will link to a git
+  repository. Use the `git-repository-url` and `git-repository-icon` options
+  in the `[output.html]` section to enable it and set its appearance.
+  [#802](https://github.com/rust-lang-nursery/mdBook/pull/802)
+- Added a `default-theme` option to the `[output.html]` section.
+  [#804](https://github.com/rust-lang-nursery/mdBook/pull/804)
+
+### Changed
+- 💥 Header ID anchors no longer add an arbitrary `a` character for headers
+  that start with a non-ascii-alphabetic character.
+  [#788](https://github.com/rust-lang-nursery/mdBook/pull/788)
+
+### Fixed
+- Fix websocket hostname usage
+  [#865](https://github.com/rust-lang-nursery/mdBook/pull/865)
+- Fixing links in print.html
+  [#866](https://github.com/rust-lang-nursery/mdBook/pull/866)
+
+## mdBook 0.2.2 (2018-10-19)
+[7e2e095...2c20c99](https://github.com/rust-lang-nursery/mdBook/compare/7e2e095...2c20c99)
+
+### Added
+- 🎉 Process-based custom preprocessors. See [the
+  docs](https://rust-lang-nursery.github.io/mdBook/for_developers/preprocessors.html)
+  for more.
+  [#792](https://github.com/rust-lang-nursery/mdBook/pull/792)
+
+- 🎉 Configurable preprocessors.
+
+  Added `build.use-default-preprocessors` boolean TOML key to allow disabling
+  the built-in `links` and `index` preprocessors.
+
+  Added `[preprocessor]` TOML tables to configure each preprocessor.
+
+  Specifying `[preprocessor.links]` or `[preprocessor.index]` will enable the
+  respective built-in preprocessor if `build.use-default-preprocessors` is
+  `false`.
+
+  Added `fn supports_renderer(&self, renderer: &str) -> bool` to the
+  `Preprocessor` trait to specify if the preprocessor supports the given
+  renderer. The default implementation always returns `true`.
+
+  `Preprocessor::run` now takes a book by value instead of a mutable
+  reference. It should return a `Book` value with the intended modifications.
+
+  Added `PreprocessorContext::renderer` to indicate the renderer being used.
+
+  [#658](https://github.com/rust-lang-nursery/mdBook/pull/658)
+  [#787](https://github.com/rust-lang-nursery/mdBook/pull/787)
+
+### Fixed
+- Fix paths to additional CSS and JavaScript files
+  [#777](https://github.com/rust-lang-nursery/mdBook/pull/777)
+- Ensure section numbers are correctly incremented after a horizontal
+  separator
+  [#790](https://github.com/rust-lang-nursery/mdBook/pull/790)
+
+## mdBook 0.2.1 (2018-08-22)
+[91ffca1...7e2e095](https://github.com/rust-lang-nursery/mdBook/compare/91ffca1...7e2e095)
+
+### Changed
+- Update to handlebars-rs 1.0
+  [#761](https://github.com/rust-lang-nursery/mdBook/pull/761)
+
+### Fixed
+- Fix table colors, broken by Stylus -> CSS transition
+  [#765](https://github.com/rust-lang-nursery/mdBook/pull/765)
+
+## mdBook 0.2.0 (2018-08-02)
+
+### Changed
+- 💥 This release changes how links are handled in mdBook. Previously, relative
+  links were interpreted relative to the book's root. In `0.2.0`+ links are
+  relative to the page they are in, and use the `.md` extension. This has [several
+  advantages](https://github.com/rust-lang-nursery/mdBook/pull/603#issue-166701447),
+  such as making links work in other markdown viewers like GitHub. You will
+  likely have to change links in your book to accommodate this change. For
+  example, a book with this layout:
+
+  ```
+  chapter_1/
+      section_1.md
+      section_2.md
+  SUMMARY.md
+  ```
+
+  Previously a link in `section_1.md` to `section_2.md` would look like this:
+  ```markdown
+  [section_2](chapter_1/section_2.html)
+  ```
+
+  Now it must be changed to this:
+  ```markdown
+  [section_2](section_2.md)
+  ```
+
+- 💥 `mdbook test --library-path` now accepts a comma-delimited list of
+  arguments rather than taking all following arguments. This makes it easier
+  to handle the trailing book directory argument without always needing to put
+  ` -- ` before it. Multiple instances of the option continue to be accepted:
+  `mdbook test -L foo -L bar`.
+
+- 💥 `mdbook serve` has some of its options renamed for clarity. See `mdbook
+  help serve` for details.
+
+- Embedded rust playpens now use the "stable" playground API.
+  [#754](https://github.com/rust-lang-nursery/mdBook/pull/754)
+
+### Fixed
+- Escaped includes (`\{{#include file.rs}}`) will now render correctly.
+  [f30ce01](https://github.com/rust-lang-nursery/mdBook/commit/f30ce0184d71e342141145472bf816419d30a2c5)
+- `index.html` will now render correctly when the book's first section is
+  inside a subdirectory.
+  [#756](https://github.com/rust-lang-nursery/mdBook/pull/756)

CONTRIBUTING.md

@@ -48,29 +48,53 @@ mdBook builds on stable Rust, if you want to build mdBook from source, here are
 
 The resulting binary can be found in `mdBook/target/debug/` under the name `mdBook` or `mdBook.exe`.
 
+### Code Quality
 
-### Making changes to the style
+We love code quality and Rust has some excellent tools to assist you with contributions.
 
-mdBook doesn't use CSS directly but uses [Stylus](http://stylus-lang.com/), a CSS-preprocessor which compiles to CSS.
+#### Formatting Code with rustfmt
 
-When you want to change the style, it is important to not change the CSS directly because any manual modification to
-the CSS files will be overwritten when compiling the stylus files. Instead, you should make your changes directly in the
-[stylus files](https://github.com/rust-lang-nursery/mdBook/tree/master/src/theme/stylus) and regenerate the CSS.
+Before you make your Pull Request to the project, please run it through the `rustfmt` utility.
+This will ensure we have good quality source code that is better for us all to maintain.
 
-For this to work, you first need [Node and NPM](https://nodejs.org/en/) installed on your machine.
-Then run the following command to install both [stylus](http://stylus-lang.com/) and [nib](https://tj.github.io/nib/), you might need `sudo` to install successfully.
+[rustfmt](https://github.com/rust-lang-nursery/rustfmt) has a lot more information on the project.
+The quick guide is
 
-```
-npm install -g stylus nib
-```
+1. Install it
+    ```
+    rustup component add rustfmt
+    ```
+1. You can now run `rustfmt` on a single file simply by...
+    ```
+    rustfmt src/path/to/your/file.rs
+    ```
+   ... or you can format the entire project with
+   ```
+   cargo fmt
+   ```
+   When run through `cargo` it will format all bin and lib files in the current crate.
 
-When that finished, you can simply regenerate the CSS files by building mdBook with the following command:
+For more information, such as running it from your favourite editor, please see the `rustfmt` project. [rustfmt](https://github.com/rust-lang-nursery/rustfmt)
 
-```
-cargo build --features=regenerate-css
-```
 
-This should automatically call the appropriate stylus command to recompile the files to CSS and include them in the project.
+#### Finding Issues with Clippy
+
+Clippy is a code analyser/linter detecting mistakes, and therfore helps to improve your code.
+Like formatting your code with `rustfmt`, running clippy regularly and before your Pull Request will
+help us maintain awesome code.
+
+The best documentation can be found over at [rust-clippy](https://github.com/rust-lang-nursery/rust-clippy)
+
+1. To install
+    ```
+    rustup component add clippy
+    ```
+2. Running clippy
+    ```
+    cargo clippy
+    ```
+
+Clippy has an ever growing list of checks, that are managed in [lint files](https://rust-lang-nursery.github.io/rust-clippy/master/index.html).
 
 ### Making a pull-request
 

Cargo.toml

@@ -1,73 +1,67 @@
 [package]
 name = "mdbook"
-version = "0.1.8"
-authors = ["Mathieu David <mathieudavid@mathieudavid.org>", "Michael-F-Bryan <michaelfbryan@gmail.com>"]
-description = "Create books from markdown files"
+version = "0.3.3"
+authors = [
+    "Mathieu David <mathieudavid@mathieudavid.org>",
+    "Michael-F-Bryan <michaelfbryan@gmail.com>",
+    "Matt Ickstadt <mattico8@gmail.com>"
+]
 documentation = "http://rust-lang-nursery.github.io/mdBook/index.html"
-repository = "https://github.com/rust-lang-nursery/mdBook"
+edition = "2018"
+exclude = ["/book-example/*"]
 keywords = ["book", "gitbook", "rustbook", "markdown"]
 license = "MPL-2.0"
 readme = "README.md"
-build = "build.rs"
-exclude = [
-    "book-example/*",
-    "src/theme/stylus/**",
-]
+repository = "https://github.com/rust-lang-nursery/mdBook"
+description = "Creates a book from markdown files"
 
 [dependencies]
-clap = "2.24"
 chrono = "0.4"
-handlebars = "0.32"
-serde = "1.0"
-serde_derive = "1.0"
-error-chain = "0.11"
-serde_json = "1.0"
-pulldown-cmark = "0.1.2"
+clap = "2.24"
+env_logger = "0.6"
+error-chain = "0.12"
+handlebars = { version = "2.0", default-features = false, features = ["no_dir_source"] }
+itertools = "0.8"
 lazy_static = "1.0"
 log = "0.4"
-env_logger = "0.5.0-rc.1"
-toml = "0.4"
 memchr = "2.0"
 open = "1.1"
+pulldown-cmark = "0.5"
 regex = "1.0.0"
-tempfile = "3.0"
-itertools = "0.7"
+serde = "1.0"
+serde_derive = "1.0"
+serde_json = "1.0"
 shlex = "0.1"
-toml-query = "0.6"
+tempfile = "3.0"
+toml = "0.5.1"
+toml-query = "0.9"
 
 # Watch feature
 notify = { version = "4.0", optional = true }
-time = { version = "0.1.34", optional = true }
-crossbeam = { version = "0.3", optional = true }
+gitignore = { version = "1.0", optional = true }
 
 # Serve feature
 iron = { version = "0.6", optional = true }
 staticfile = { version = "0.5", optional = true }
-ws = { version = "0.7", optional = true}
+ws = { version = "0.9", optional = true}
 
 # Search feature
-elasticlunr-rs = { version = "2.2", optional = true, default-features = false }
-ammonia = { version = "1.1", optional = true }
-
-[build-dependencies]
-error-chain = "0.11"
+elasticlunr-rs = { version = "2.3", optional = true, default-features = false }
+ammonia = { version = "3", optional = true }
 
 [dev-dependencies]
 select = "0.4"
-pretty_assertions = "0.5"
+pretty_assertions = "0.6"
 walkdir = "2.0"
-pulldown-cmark-to-cmark = "1.1.0"
 
 [features]
 default = ["output", "watch", "serve", "search"]
 debug = []
 output = []
-regenerate-css = []
-watch = ["notify", "time", "crossbeam"]
+watch = ["notify", "gitignore"]
 serve = ["iron", "staticfile", "ws"]
 search = ["elasticlunr-rs", "ammonia"]
 
 [[bin]]
 doc = false
 name = "mdbook"
-path = "src/bin/mdbook.rs"

README.md

@@ -1,25 +1,8 @@
 # mdBook
 
-<table>
-    <tr>
-        <td><strong>Linux / OS X</strong></td>
-        <td>
-            <a href="https://travis-ci.org/rust-lang-nursery/mdBook"><img src="https://travis-ci.org/rust-lang-nursery/mdBook.svg?branch=master"></a>
-        </td>
-    </tr>
-    <tr>
-        <td><strong>Windows</strong></td>
-        <td>
-            <a href="https://ci.appveyor.com/project/rust-lang-libs/mdbook"><img src="https://ci.appveyor.com/api/projects/status/ysyke2rvo85sni55?svg=true"></a>
-        </td>
-    </tr>
-    <tr>
-        <td colspan="2">
-            <a href="https://crates.io/crates/mdbook"><img src="https://img.shields.io/crates/v/mdbook.svg"></a>
-            <a href="LICENSE"><img src="https://img.shields.io/github/license/rust-lang-nursery/mdBook.svg"></a>
-        </td>
-    </tr>
-</table>
+[![Build Status](https://github.com/rust-lang-nursery/mdBook/workflows/CI/badge.svg)](https://github.com/rust-lang-nursery/mdBook/actions?workflow=CI)
+[![crates.io](https://img.shields.io/crates/v/mdbook.svg)](https://crates.io/crates/mdbook)
+[![LICENSE](https://img.shields.io/github/license/rust-lang-nursery/mdBook.svg)](LICENSE)
 
 mdBook is a utility to create modern online books from Markdown files.
 
@@ -41,7 +24,7 @@ There are multiple ways to install mdBook.
 
 2. **From Crates.io**
 
-   This requires at least [Rust] 1.20 and Cargo to be installed. Once you have installed
+   This requires at least [Rust] 1.35 and Cargo to be installed. Once you have installed
    Rust, type the following in the terminal:
 
    ```
@@ -57,7 +40,7 @@ There are multiple ways to install mdBook.
    another CI server, we recommend that you specify a semver version range for
    mdBook when you install it through your script!
 
-   This will constrain the server to install the latests **non-breaking**
+   This will constrain the server to install the latest **non-breaking**
    version of mdBook and will prevent your books from failing to build because
    we released a new version. For example:
 
@@ -65,7 +48,7 @@ There are multiple ways to install mdBook.
    cargo install mdbook --vers "^0.1.0"
    ```
 
-3. **From Git**  
+3. **From Git**
 
    The version published to crates.io will ever so slightly be behind the
    version hosted here on GitHub. If you need the latest version you can build
@@ -77,7 +60,7 @@ There are multiple ways to install mdBook.
 
    Again, make sure to add the Cargo bin directory to your `PATH`.
 
-4. **For Contributions**  
+4. **For Contributions**
 
    If you want to contribute to mdBook you will have to clone the repository on
    your local machine:
@@ -145,6 +128,60 @@ explanation, check out the [User Guide].
 
     Delete directory in which generated book is located.
 
+### 3rd Party Plugins
+
+The way a book is loaded and rendered can be configured by the user via third
+party plugins. These plugins are just programs which will be invoked during the
+build process and are split into roughly two categories, *preprocessors* and
+*renderers*.
+
+Preprocessors are used to transform a book before it is sent to a renderer.
+One example would be to replace all occurrences of
+`{{#include some_file.ext}}` with the contents of that file. Some existing
+preprocessors are:
+
+- `index` - a built-in preprocessor (enabled by default) which will transform
+  all `README.md` chapters to `index.md` so `foo/README.md` can be accessed via
+  the url `foo/` when published to a browser
+- `links` - a built-in preprocessor (enabled by default) for expanding the
+  `{{# playpen}}` and `{{# include}}` helpers in a chapter.
+
+Renderers are given the final book so they can do something with it. This is
+typically used for, as the name suggests, rendering the document in a particular
+format, however there's nothing stopping a renderer from doing static analysis
+of a book in order to validate links or run tests. Some existing renderers are:
+
+- `html` - the built-in renderer which will generate a HTML version of the book
+- `markdown` - the built-in renderer (disabled by default) which will run
+  preprocessors then output the resulting Markdown. Useful for debugging
+  preprocessors.
+- [`linkcheck`] - a backend which will check that all links are valid
+- [`epub`] - an experimental EPUB generator
+
+> **Note for Developers:** Feel free to send us a PR if you've developed your
+> own plugin and want it mentioned here.
+
+A preprocessor or renderer is enabled by installing the appropriate program and
+then mentioning it in the book's `book.toml` file.
+
+```console
+$ cargo install mdbook-linkcheck
+$ edit book.toml && cat book.toml
+[book]
+title = "My Awesome Book"
+authors = ["Michael-F-Bryan"]
+
+[output.html]
+
+[output.linkcheck]  # enable the "mdbook-linkcheck" renderer
+
+$ mdbook build
+2018-10-20 13:57:51 [INFO] (mdbook::book): Book building has started
+2018-10-20 13:57:51 [INFO] (mdbook::book): Running the html backend
+2018-10-20 13:57:53 [INFO] (mdbook::book): Running the linkcheck backend
+```
+
+For more information on the plugin system, consult the [User Guide].
 
 ### As a library
 
@@ -188,4 +225,6 @@ All the code in this repository is released under the ***Mozilla Public License
 [releases]: https://github.com/rust-lang-nursery/mdBook/releases
 [Rust]: https://www.rust-lang.org/
 [CLI docs]: http://rust-lang-nursery.github.io/mdBook/cli/init.html
-[master-docs]: http://rust-lang-nursery.github.io/mdBook/mdbook/
+[master-docs]: http://rust-lang-nursery.github.io/mdBook/
+[`linkcheck`]: https://crates.io/crates/mdbook-linkcheck
+[`epub`]: https://crates.io/crates/mdbook-epub

appveyor.yml

@@ -1,69 +0,0 @@
-environment:
-  global:
-    PROJECT_NAME: mdBook
-    nodejs_version: "6"
-  matrix:
-    # Stable channel
-    - TARGET: i686-pc-windows-msvc
-      RUST_CHANNEL: stable
-    - TARGET: x86_64-pc-windows-msvc
-      RUST_CHANNEL: stable
-    # Beta channel
-    - TARGET: i686-pc-windows-msvc
-      RUST_CHANNEL: beta
-    - TARGET: x86_64-pc-windows-msvc
-      RUST_CHANNEL: beta
-    # Nightly channel
-    - TARGET: i686-pc-windows-msvc
-      RUST_CHANNEL: nightly
-    - TARGET: x86_64-pc-windows-msvc
-      RUST_CHANNEL: nightly
-
-# Install Rust and Cargo
-install:
-  - ps: >-
-      If ($Env:TARGET -eq 'x86_64-pc-windows-gnu') {
-        $Env:PATH += ';C:\msys64\mingw64\bin'
-      } ElseIf ($Env:TARGET -eq 'i686-pc-windows-gnu') {
-        $Env:PATH += ';C:\msys64\mingw32\bin'
-      }
-  - curl -sSf -o rustup-init.exe https://win.rustup.rs/
-  - rustup-init.exe -y --default-host %TARGET% --default-toolchain %RUST_CHANNEL%
-  - set PATH=%PATH%;C:\Users\appveyor\.cargo\bin
-  - rustc -Vv
-  - cargo -V
-  - ps: Install-Product node $env:nodejs_version
-  - node --version
-  - npm --version
-  - npm install -g stylus nib
-
-build: false
-
-# Equivalent to Travis' `script` phase
-test_script:
-  - cargo build --verbose
-  - cargo build --verbose --features=regenerate-css
-  - cargo test --verbose
-
-before_deploy:
-  # Generate artifacts for release
-  - cargo build --release
-  - mkdir staging
-  - copy target\release\mdbook.exe staging
-  - cd staging
-  - 7z a ../%PROJECT_NAME%-%APPVEYOR_REPO_TAG_NAME%-%TARGET%.zip *
-  - appveyor PushArtifact ../%PROJECT_NAME%-%APPVEYOR_REPO_TAG_NAME%-%TARGET%.zip
-
-deploy:
-  description: 'Windows release'
-  artifact: /.*\.zip/
-  auth_token:
-    secure: QQhjKVyz7mpjlyGhlXytbFQQfKFQWTahHkD+B0NzIUoEVqO7ZLWjnoWasvLqW4nE
-  provider: GitHub
-  on:
-    RUST_CHANNEL: stable
-    appveyor_repo_tag: true
-
-branches:
-  only:
-    - master

book-example/book.toml

@@ -2,12 +2,14 @@
 title = "mdBook Documentation"
 description = "Create book from markdown files. Like Gitbook but implemented in Rust"
 authors = ["Mathieu David", "Michael-F-Bryan"]
+language = "en"
 
 [output.html]
 mathjax-support = true
 
 [output.html.playpen]
 editable = true
+line-numbers = true
 
 [output.html.search]
 limit-results = 20

book-example/src/README.md

@@ -1,15 +1,25 @@
 # mdBook
 
-**mdBook** is a command line tool and Rust crate to create books using Markdown files. It's very similar to Gitbook but written in [Rust](http://www.rust-lang.org).
+**mdBook** is a command line tool and Rust crate to create books using Markdown
+files. It's very similar to Gitbook but written in
+[Rust](http://www.rust-lang.org).
 
-What you are reading serves as an example of the output of mdBook and at the same time as a high-level documentation.
+What you are reading serves as an example of the output of mdBook and at the
+same time as a high-level documentation.
 
-mdBook is free and open source, you can find the source code on [Github](https://github.com/rust-lang-nursery/mdBook). Issues and feature requests can be posted on the [Github Issue tracker](https://github.com/rust-lang-nursery/mdBook/issues).
+mdBook is free and open source, you can find the source code on
+[GitHub](https://github.com/rust-lang-nursery/mdBook). Issues and feature
+requests can be posted on the [GitHub issue
+tracker](https://github.com/rust-lang-nursery/mdBook/issues).
 
 ## API docs
 
-Alongside this book you can also read the [API docs](https://docs.rs/mdbook/*/mdbook/) generated by Rustdoc if you would like to use mdBook as a crate or write a new renderer and need a more low-level overview.
+Alongside this book you can also read the [API
+docs](https://docs.rs/mdbook/*/mdbook/) generated by Rustdoc if you would like
+to use mdBook as a crate or write a new renderer and need a more low-level
+overview.
 
 ## License
 
-mdBook, all the source code, is released under the [Mozilla Public License v2.0](https://www.mozilla.org/MPL/2.0/)
+mdBook, all the source code, is released under the [Mozilla Public License
+v2.0](https://www.mozilla.org/MPL/2.0/).

book-example/src/SUMMARY.md

@@ -20,7 +20,7 @@
 - [Continuous Integration](continuous-integration.md)
 - [For Developers](for_developers/README.md)
     - [Preprocessors](for_developers/preprocessors.md)
-    - [Alternate Backends](for_developers/backends.md)
+    - [Alternative Backends](for_developers/backends.md)
 
 -----------
 

book-example/src/cli/README.md

@@ -1,30 +1,49 @@
 # Command Line Tool
 
-mdBook can be used either as a command line tool or a [Rust crate](https://crates.io/crates/mdbook).
-Let's focus on the command line tool capabilities first.
+mdBook can be used either as a command line tool or a [Rust
+crate](https://crates.io/crates/mdbook). Let's focus on the command line tool
+capabilities first.
 
-## Install
+## Install From Binaries
+
+Precompiled binaries are provided for major platforms on a best-effort basis.
+Visit [the releases page](https://github.com/rust-lang-nursery/mdBook/releases)
+to download the appropriate version for your platform.
+
+## Install From Source
+
+mdBook can also be installed from source
 
 ### Pre-requisite
 
-mdBook is written in **[Rust](https://www.rust-lang.org/)** and therefore needs to be compiled with **Cargo**, because we don't yet offer ready-to-go binaries. If you haven't already installed Rust, please go ahead and [install it](https://www.rust-lang.org/downloads.html) now.
+mdBook is written in **[Rust](https://www.rust-lang.org/)** and therefore needs
+to be compiled with **Cargo**. If you haven't already installed Rust, please go
+ahead and [install it](https://www.rust-lang.org/tools/install) now.
 
 ### Install Crates.io version
 
-Installing mdBook is relatively easy if you already have Rust and Cargo installed. You just have to type this snippet in your terminal:
+Installing mdBook is relatively easy if you already have Rust and Cargo
+installed. You just have to type this snippet in your terminal:
 
 ```bash
 cargo install mdbook
 ```
 
-This will fetch the source code from [Crates.io](https://crates.io/) and compile it. You will have to add Cargo's `bin` directory to your `PATH`.
+This will fetch the source code for the latest release from
+[Crates.io](https://crates.io/) and compile it. You will have to add Cargo's
+`bin` directory to your `PATH`.
 
-Run `mdbook help` in your terminal to verify if it works. Congratulations, you have installed mdBook!
+Run `mdbook help` in your terminal to verify if it works. Congratulations, you
+have installed mdBook!
 
 
 ### Install Git version
 
-The **[git version](https://github.com/rust-lang-nursery/mdBook)** contains all the latest bug-fixes and features, that will be released in the next version on **Crates.io**, if you can't wait until the next release. You can build the git version yourself. Open your terminal and navigate to the directory of you choice. We need to clone the git repository and then build it with Cargo.
+The **[git version](https://github.com/rust-lang-nursery/mdBook)** contains all
+the latest bug-fixes and features, that will be released in the next version on
+**Crates.io**, if you can't wait until the next release. You can build the git
+version yourself. Open your terminal and navigate to the directory of you
+choice. We need to clone the git repository and then build it with Cargo.
 
 ```bash
 git clone --depth=1 https://github.com/rust-lang-nursery/mdBook.git
@@ -32,4 +51,5 @@ cd mdBook
 cargo build --release
 ```
 
-The executable `mdbook` will be in the `./target/release` folder, this should be added to the path.
+The executable `mdbook` will be in the `./target/release` folder, this should be
+added to the path.

book-example/src/cli/build.md

@@ -6,16 +6,16 @@ The build command is used to render your book:
 mdbook build
 ```
 
-It will try to parse your `SUMMARY.md` file to understand the structure of your book
-and fetch the corresponding files.
+It will try to parse your `SUMMARY.md` file to understand the structure of your
+book and fetch the corresponding files.
 
 The rendered output will maintain the same directory structure as the source for
 convenience. Large books will therefore remain structured when rendered.
 
 #### Specify a directory
 
-Like `init`, the `build` command can take a directory as an argument to use
-instead of the current working directory.
+The `build` command can take a directory as an argument to use as the book's
+root instead of the current working directory.
 
 ```bash
 mdbook build path/to/book
@@ -23,13 +23,17 @@ mdbook build path/to/book
 
 #### --open
 
-When you use the `--open` (`-o`) option, mdbook will open the rendered book in
+When you use the `--open` (`-o`) flag, mdbook will open the rendered book in
 your default web browser after building it.
 
 #### --dest-dir
 
-The `--dest-dir` (`-d`) option allows you to change the output directory for your book.
+The `--dest-dir` (`-d`) option allows you to change the output directory for the
+book. Relative paths are interpreted relative to the book's root directory. If
+not specified it will default to the value of the `build.build-dir` key in
+`book.toml`, or to `./book`.
 
 -------------------
 
-***note:*** *make sure to run the build command in the root directory and not in the source directory*
+***Note:*** *Make sure to run the build command in the root directory and not in
+the source directory*

book-example/src/cli/clean.md

@@ -7,12 +7,21 @@ artifacts.
 mdbook clean
 ```
 
-It will try to delete the built book. If a path is provided, it will be used.
-
 #### Specify a directory
 
-Like `init`, the `clean` command can take a directory as an argument to use
-instead of the normal build directory.
+The `clean` command can take a directory as an argument to use as the book's
+root instead of the current working directory.
+
+```bash
+mdbook clean path/to/book
+```
+
+#### --dest-dir
+
+The `--dest-dir` (`-d`) option allows you to override the book's output
+directory, which will be deleted by this command. Relative paths are interpreted
+relative to the book's root directory. If not specified it will default to the
+value of the `build.build-dir` key in `book.toml`, or to `./book`.
 
 ```bash
 mdbook clean --dest-dir=path/to/book

book-example/src/cli/init.md

@@ -1,5 +1,7 @@
 # The init command
-There is some minimal boilerplate that is the same for every new book. It's for this purpose that mdBook includes an `init` command.
+
+There is some minimal boilerplate that is the same for every new book. It's for
+this purpose that mdBook includes an `init` command.
 
 The `init` command is used like this:
 
@@ -7,7 +9,8 @@ The `init` command is used like this:
 mdbook init
 ```
 
-When using the `init` command for the first time, a couple of files will be set up for you:
+When using the `init` command for the first time, a couple of files will be set
+up for you:
 ```bash
 book-test/
 ├── book
@@ -16,30 +19,36 @@ book-test/
     └── SUMMARY.md
 ```
 
-- The `src` directory is were you write your book in markdown. It contains all the source files,
-configuration files, etc.
+- The `src` directory is were you write your book in markdown. It contains all
+  the source files, configuration files, etc.
 
-- The `book` directory is where your book is rendered. All the output is ready to be uploaded
-to a server to be seen by your audience.
+- The `book` directory is where your book is rendered. All the output is ready
+  to be uploaded to a server to be seen by your audience.
 
-- The `SUMMARY.md` file is the most important file, it's the skeleton of your book and is discussed in more detail in another  [chapter](format/summary.html).
+- The `SUMMARY.md` file is the most important file, it's the skeleton of your
+  book and is discussed in more detail [in another
+  chapter](../format/summary.md)
 
-#### Tip & Trick: Hidden Feature
-When a `SUMMARY.md` file already exists, the `init` command will first parse it and generate the missing files according to the paths used in the `SUMMARY.md`. This allows you to think and create the whole structure of your book and then let mdBook generate it for you.
+#### Tip: Generate chapters from SUMMARY.md
+
+When a `SUMMARY.md` file already exists, the `init` command will first parse it
+and generate the missing files according to the paths used in the `SUMMARY.md`.
+This allows you to think and create the whole structure of your book and then
+let mdBook generate it for you.
 
 #### Specify a directory
 
-When using the `init` command, you can also specify a directory, instead of using the current working directory,
-by appending a path to the command:
+The `init` command can take a directory as an argument to use as the book's root
+instead of the current working directory.
 
 ```bash
 mdbook init path/to/book
 ```
 
-## --theme
+#### --theme
 
-When you use the `--theme` argument, the default theme will be copied into a directory
-called `theme` in your source directory so that you can modify it.
+When you use the `--theme` flag, the default theme will be copied into a
+directory called `theme` in your source directory so that you can modify it.
 
-The theme is selectively overwritten, this means that if you don't want to overwrite a
-specific file, just delete it and the default file will be used.
+The theme is selectively overwritten, this means that if you don't want to
+overwrite a specific file, just delete it and the default file will be used.

book-example/src/cli/serve.md

@@ -1,40 +1,48 @@
 # The serve command
 
-The `serve` command is useful when you want to preview your book. It also does hot reloading of the webpage whenever a file changes.
-It achieves this by serving the books content over `localhost:3000` (unless otherwise configured, see below) and runs a websocket server on `localhost:3001` which triggers the reloads.
-This preferred by many for writing books with mdbook because it allows for you to see the result of your work instantly after every file change.
+The serve command is used to preview a book by serving it over HTTP at
+`localhost:3000` by default. Additionally it watches the book's directory for
+changes, rebuilding the book and refreshing clients for each change. A websocket
+connection is used to trigger the client-side refresh.
+
+***Note:*** *The `serve` command is for testing a book's HTML output, and is not
+intended to be a complete HTTP server for a website.*
 
 #### Specify a directory
 
-Like `watch`, `serve` can take a directory as an argument to use instead of
-the current working directory.
+The `serve` command can take a directory as an argument to use as the book's
+root instead of the current working directory.
 
 ```bash
 mdbook serve path/to/book
 ```
 
-
 #### Server options
 
-`serve` has four options: the http port, the websocket port, the interface to serve on, and the public address of the server so that the browser may reach the websocket server.
+`serve` has four options: the HTTP port, the WebSocket port, the HTTP hostname
+to listen on, and the hostname for the browser to connect to for WebSockets.
 
-For example: suppose you had an nginx server for SSL termination which has a public address of 192.168.1.100 on port 80 and proxied that to 127.0.0.1 on port 8000. To run use the nginx proxy do:
+For example: suppose you have an nginx server for SSL termination which has a
+public address of 192.168.1.100 on port 80 and proxied that to 127.0.0.1 on port
+8000\. To run use the nginx proxy do:
 
 ```bash
-mdbook serve path/to/book -p 8000 -i 127.0.0.1 -a 192.168.1.100
+mdbook serve path/to/book -p 8000 -n 127.0.0.1 --websocket-hostname 192.168.1.100
 ```
 
-If you were to want live reloading for this you would need to proxy the websocket calls through nginx as well from `192.168.1.100:<WS_PORT>` to `127.0.0.1:<WS_PORT>`. The `-w` flag allows for the websocket port to be configured.
+If you were to want live reloading for this you would need to proxy the
+websocket calls through nginx as well from `192.168.1.100:<WS_PORT>` to
+`127.0.0.1:<WS_PORT>`. The `-w` flag allows for the websocket port to be
+configured.
 
 #### --open
 
-When you use the `--open` (`-o`) option, mdbook will open the book in your
-your default web browser after starting the server.
+When you use the `--open` (`-o`) flag, mdbook will open the book in your
+default web browser after starting the server.
 
 #### --dest-dir
 
-The `--dest-dir` (`-d`) option allows you to change the output directory for your book.
-
------
-
-***note:*** *the `serve` command has not gotten a lot of testing yet, there could be some rough edges. If you discover a problem, please report it [on Github](https://github.com/rust-lang-nursery/mdBook/issues)*
+The `--dest-dir` (`-d`) option allows you to change the output directory for the
+book. Relative paths are interpreted relative to the book's root directory. If
+not specified it will default to the value of the `build.build-dir` key in
+`book.toml`, or to `./book`.

book-example/src/cli/test.md

@@ -1,19 +1,53 @@
 # The test command
 
-When writing a book, you sometimes need to automate some tests. For example, [The Rust Programming Book](https://doc.rust-lang.org/stable/book/) uses a lot of code examples that could get outdated.
-Therefore it is very important for them to be able to automatically test these code examples.
+When writing a book, you sometimes need to automate some tests. For example,
+[The Rust Programming Book](https://doc.rust-lang.org/stable/book/) uses a lot
+of code examples that could get outdated. Therefore it is very important for
+them to be able to automatically test these code examples.
 
-mdBook supports a `test` command that will run all available tests in mdBook. At the moment, only one test is available:
-*"Test Rust code examples using Rustdoc"*, but I hope this will be expanded in the future to include more tests like:
+mdBook supports a `test` command that will run all available tests in a book. At
+the moment, only rustdoc tests are supported, but this may be expanded upon in
+the future.
 
-- checking for broken links
-- checking for unused files
-- ...
+#### Disable tests on a code block
 
-In the future I would like the user to be able to enable / disable test from the `book.toml` configuration file and support custom tests.
+rustdoc doesn't test code blocks which contain the `ignore` attribute:
+
+    ```rust,ignore
+    fn main() {}
+    ```
+
+rustdoc also doesn't test code blocks which specify a language other than Rust:
+
+    ```markdown
+    **Foo**: _bar_
+    ```
+
+rustdoc *does* test code blocks which have no language specified:
+
+    ```
+    This is going to cause an error!
+    ```
+
+#### Specify a directory
+
+The `test` command can take a directory as an argument to use as the book's root
+instead of the current working directory.
 
-**How to use it:**
 ```bash
-$ mdbook test
-[*]: Testing file: "/mdBook/book-example/src/README.md”
+mdbook test path/to/book
 ```
+
+#### --library-path
+
+The `--library-path` (`-L`) option allows you to add directories to the library
+search path used by `rustdoc` when it builds and tests the examples. Multiple
+directories can be specified with multiple options (`-L foo -L bar`) or with a
+comma-delimited list (`-L foo,bar`).
+
+#### --dest-dir
+
+The `--dest-dir` (`-d`) option allows you to change the output directory for the
+book. Relative paths are interpreted relative to the book's root directory. If
+not specified it will default to the value of the `build.build-dir` key in
+`book.toml`, or to `./book`.

book-example/src/cli/watch.md

@@ -1,12 +1,14 @@
 # The watch command
 
-The `watch` command is useful when you want your book to be rendered on every file change.
-You could repeatedly issue `mdbook build` every time a file is changed. But using `mdbook watch` once will watch your files and will trigger a build automatically whenever you modify a file.
+The `watch` command is useful when you want your book to be rendered on every
+file change. You could repeatedly issue `mdbook build` every time a file is
+changed. But using `mdbook watch` once will watch your files and will trigger a
+build automatically whenever you modify a file.
 
 #### Specify a directory
 
-Like `init` and `build`, `watch` can take a directory as an argument to use
-instead of the current working directory.
+The `watch` command can take a directory as an argument to use as the book's
+root instead of the current working directory.
 
 ```bash
 mdbook watch path/to/book
@@ -19,8 +21,7 @@ your default web browser.
 
 #### --dest-dir
 
-The `--dest-dir` (`-d`) option allows you to change the output directory for your book.
-
------
-
-***note:*** *the `watch` command has not gotten a lot of testing yet, there could be some rough edges. If you discover a problem, please report it [on Github](https://github.com/rust-lang-nursery/mdBook/issues)*
+The `--dest-dir` (`-d`) option allows you to change the output directory for the
+book. Relative paths are interpreted relative to the book's root directory. If
+not specified it will default to the value of the `build.build-dir` key in
+`book.toml`, or to `./book`.

book-example/src/continuous-integration.md

@@ -22,11 +22,11 @@ rust:
 
 before_script:
   - (test -x $HOME/.cargo/bin/cargo-install-update || cargo install cargo-update)
-  - (test -x $HOME/.cargo/bin/mdbook || cargo install --vers "^0.1" mdbook)
+  - (test -x $HOME/.cargo/bin/mdbook || cargo install --vers "^0.3" mdbook)
   - cargo install-update -a
 
 script:
-  - cd path/to/mybook && mdbook build && mdbook test
+  - mdbook build path/to/mybook && mdbook test path/to/mybook
 ```
 
 ## Deploying Your Book to GitHub Pages
@@ -34,12 +34,13 @@ script:
 Following these instructions will result in your book being published to GitHub
 pages after a successful CI run on your repository's `master` branch.
 
-First, create a new GitHub oauth token with the "public_repo" permissions (or
-"repo" for private repositories). Go to your repository's Travis CI settings
-page and add an environment variable named `GITHUB_TOKEN` that is marked secure
-and *not* shown in the logs.
+First, create a new GitHub "Personal Access Token" with the "public_repo"
+permissions (or "repo" for private repositories). Go to your repository's Travis
+CI settings page and add an environment variable named `GITHUB_TOKEN` that is
+marked secure and *not* shown in the logs.
 
-Then, add this snippet to your `.travis.yml`:
+Then, append this snippet to your `.travis.yml` and update the path to the
+`book` directory:
 
 ```yaml
 deploy:
@@ -53,3 +54,36 @@ deploy:
 ```
 
 That's it!
+
+### Deploying to GitHub Pages manually
+
+If your CI doesn't support GitHub pages, or you're deploying somewhere else
+with integrations such as Github Pages:
+ *note: you may want to use different tmp dirs*:
+
+```console
+$> git worktree add /tmp/book gh-pages
+$> mdbook build
+$> rm -rf /tmp/book/* # this won't delete the .git directory
+$> cp -rp book/* /tmp/book/
+$> cd /tmp/book
+$> git add -A
+$> git commit 'new book message'
+$> git push origin gh-pages
+$> cd -
+```
+
+Or put this into a Makefile rule:
+
+```makefile
+.PHONY: deploy
+deploy: book
+	@echo "====> deploying to github"
+	git worktree add /tmp/book gh-pages
+	rm -rf /tmp/book/*
+	cp -rp book/* /tmp/book/
+	cd /tmp/book && \
+		git add -A && \
+		git commit -m "deployed on $(shell date) by ${USER}" && \
+		git push origin gh-pages
+```

book-example/src/for_developers/README.md

@@ -1,25 +1,25 @@
 # For Developers
 
-While `mdbook` is mainly used as a command line tool, you can also import the 
+While `mdbook` is mainly used as a command line tool, you can also import the
 underlying library directly and use that to manage a book. It also has a fairly
-flexible plugin mechanism, allowing you to create your own custom tooling and 
+flexible plugin mechanism, allowing you to create your own custom tooling and
 consumers (often referred to as *backends*) if you need to do some analysis of
 the book or render it in a different format.
 
-The *For Developers* chapters are here to show you the more advanced usage of 
+The *For Developers* chapters are here to show you the more advanced usage of
 `mdbook`.
 
 The two main ways a developer can hook into the book's build process is via,
 
-- [Preprocessors](for_developers/preprocessors.html)
-- [Alternate Backends](for_developers/backends.html)
+- [Preprocessors](preprocessors.md)
+- [Alternative Backends](backends.md)
 
 
 ## The Build Process
 
 The process of rendering a book project goes through several steps.
 
-1. Load the book 
+1. Load the book
     - Parse the `book.toml`, falling back to the default `Config` if it doesn't
        exist
     - Load the book chapters into memory
@@ -32,15 +32,15 @@ The process of rendering a book project goes through several steps.
 
 The `mdbook` binary is just a wrapper around the `mdbook` crate, exposing its
 functionality as a command-line program. As such it is quite easy to create your
-own programs which use `mdbook` internally, adding your own functionality (e.g. 
+own programs which use `mdbook` internally, adding your own functionality (e.g.
 a custom preprocessor) or tweaking the build process.
 
 The easiest way to find out how to use the `mdbook` crate is by looking at the
-[API Docs]. The top level documentation explains how one would use the 
+[API Docs]. The top level documentation explains how one would use the
 [`MDBook`] type to load and build a book, while the [config] module gives a good
 explanation on the configuration system.
 
 
-[`MDBook`]: http://rust-lang-nursery.github.io/mdBook/mdbook/book/struct.MDBook.html
-[API Docs]: http://rust-lang-nursery.github.io/mdBook/mdbook/
-[config]: file:///home/michael/Documents/forks/mdBook/target/doc/mdbook/config/index.html
+[`MDBook`]: https://docs.rs/mdbook/*/mdbook/book/struct.MDBook.html
+[API Docs]: https://docs.rs/mdbook/*/mdbook/
+[config]: https://docs.rs/mdbook/*/mdbook/config/index.html

book-example/src/for_developers/backends.md

@@ -1,11 +1,11 @@
-# Alternate Backends
+# Alternative Backends
 
-A "backend" is simply a program which `mdbook` will invoke during the book 
+A "backend" is simply a program which `mdbook` will invoke during the book
 rendering process. This program is passed a JSON representation of the book and
-configuration information via `stdin`. Once the backend receives this 
+configuration information via `stdin`. Once the backend receives this
 information it is free to do whatever it wants.
 
-There are already several alternate backends on GitHub which can be used as a 
+There are already several alternative backends on GitHub which can be used as a
 rough example of how this is accomplished in practice.
 
 - [mdbook-linkcheck] - a simple program for verifying the book doesn't contain
@@ -14,24 +14,24 @@ rough example of how this is accomplished in practice.
 - [mdbook-test] - a program to run the book's contents through [rust-skeptic] to
   verify everything compiles and runs correctly (similar to `rustdoc --test`)
 
-This page will step you through creating your own alternate backend in the form
+This page will step you through creating your own alternative backend in the form
 of a simple word counting program. Although it will be written in Rust, there's
 no reason why it couldn't be accomplished using something like Python or Ruby.
 
 
 ## Setting Up
 
-First you'll want to create a new binary program and add `mdbook` as a 
+First you'll want to create a new binary program and add `mdbook` as a
 dependency.
 
-```
+```shell
 $ cargo new --bin mdbook-wordcount
-$ cd mdbook-wordcount 
+$ cd mdbook-wordcount
 $ cargo add mdbook
 ```
 
-When our `mdbook-wordcount` plugin is invoked, `mdbook` will send it a JSON 
-version of [`RenderContext`] via our plugin's `stdin`. For convenience, there's 
+When our `mdbook-wordcount` plugin is invoked, `mdbook` will send it a JSON
+version of [`RenderContext`] via our plugin's `stdin`. For convenience, there's
 a [`RenderContext::from_json()`] constructor which will load a `RenderContext`.
 
 This is all the boilerplate necessary for our backend to load the book.
@@ -49,18 +49,18 @@ fn main() {
 }
 ```
 
-> **Note:** The `RenderContext` contains a `version` field. This lets backends 
+> **Note:** The `RenderContext` contains a `version` field. This lets backends
   figure out whether they are compatible with the version of `mdbook` it's being
-  called by. This `version` comes directly from the corresponding field in 
-  `mdbook`'s `Cargo.toml`. 
-  
+  called by. This `version` comes directly from the corresponding field in
+  `mdbook`'s `Cargo.toml`.
+
   It is recommended that backends use the [`semver`] crate to inspect this field
   and emit a warning if there may be a compatibility issue.
 
 
 ## Inspecting the Book
 
-Now our backend has a copy of the book, lets count how many words are in each 
+Now our backend has a copy of the book, lets count how many words are in each
 chapter!
 
 Because the `RenderContext` contains a [`Book`] field (`book`), and a `Book` has
@@ -89,15 +89,15 @@ fn count_words(ch: &Chapter) -> usize {
 
 ## Enabling the Backend
 
-Now we've got the basics running, we want to actually use it. First, install
-the program.
+Now we've got the basics running, we want to actually use it. First, install the
+program.
 
-```
-$ cargo install
+```shell
+$ cargo install --path .
 ```
 
 Then `cd` to the particular book you'd like to count the words of and update its
-`book.toml` file. 
+`book.toml` file.
 
 ```diff
   [book]
@@ -110,18 +110,17 @@ Then `cd` to the particular book you'd like to count the words of and update its
 + [output.wordcount]
 ```
 
-When it loads a book into memory, `mdbook` will inspect your `book.toml` file 
-to try and figure out which backends to use by looking for all `output.*`
-tables. If none are provided it'll fall back to using the default HTML
-renderer. 
+When it loads a book into memory, `mdbook` will inspect your `book.toml` file to
+try and figure out which backends to use by looking for all `output.*` tables.
+If none are provided it'll fall back to using the default HTML renderer.
 
-Notably, this means if you want to add your own custom backend you'll also
-need to make sure to add the HTML backend, even if its table just stays empty.
+Notably, this means if you want to add your own custom backend you'll also need
+to make sure to add the HTML backend, even if its table just stays empty.
 
-Now you just need to build your book like normal, and everything should *Just 
+Now you just need to build your book like normal, and everything should *Just
 Work*.
 
-```
+```shell
 $ mdbook build
 ...
 2018-01-16 07:31:15 [INFO] (mdbook::renderer): Invoking the "mdbook-wordcount" renderer
@@ -141,15 +140,15 @@ Syntax highlighting: 314
 MathJax Support: 153
 Rust code specific features: 148
 For Developers: 788
-Alternate Backends: 710
+Alternative Backends: 710
 Contributors: 85
 ```
 
-The reason we didn't need to specify the full name/path of our `wordcount` 
-backend is because `mdbook` will try to *infer* the program's name via 
-convention. The executable for the `foo` backend is typically called 
+The reason we didn't need to specify the full name/path of our `wordcount`
+backend is because `mdbook` will try to *infer* the program's name via
+convention. The executable for the `foo` backend is typically called
 `mdbook-foo`, with an associated `[output.foo]` entry in the `book.toml`. To
-explicitly tell `mdbook` what command to invoke (it may require command-line 
+explicitly tell `mdbook` what command to invoke (it may require command-line
 arguments or be an interpreted script), you can use the `command` field.
 
 ```diff
@@ -168,16 +167,16 @@ arguments or be an interpreted script), you can use the `command` field.
 ## Configuration
 
 Now imagine you don't want to count the number of words on a particular chapter
-(it might be generated text/code, etc). The canonical way to do this is via
-the usual `book.toml` configuration file by adding items to your `[output.foo]` 
-table. 
+(it might be generated text/code, etc). The canonical way to do this is via the
+usual `book.toml` configuration file by adding items to your `[output.foo]`
+table.
 
 The `Config` can be treated roughly as a nested hashmap which lets you call
 methods like `get()` to access the config's contents, with a
-`get_deserialized()` convenience method for retrieving a value and
-automatically deserializing to some arbitrary type `T`.
+`get_deserialized()` convenience method for retrieving a value and automatically
+deserializing to some arbitrary type `T`.
 
-To implement this, we'll create our own serializable `WordcountConfig` struct 
+To implement this, we'll create our own serializable `WordcountConfig` struct
 which will encapsulate all configuration for this backend.
 
 First add `serde` and `serde_derive` to your `Cargo.toml`,
@@ -212,13 +211,13 @@ and then add a check to make sure we skip ignored chapters.
 +     let cfg: WordcountConfig = ctx.config
 +         .get_deserialized("output.wordcount")
 +         .unwrap_or_default();
-  
+
       for item in ctx.book.iter() {
           if let BookItem::Chapter(ref ch) = *item {
 +             if cfg.ignores.contains(&ch.name) {
 +                 continue;
 +             }
-+ 
++
               let num_words = count_words(ch);
               println!("{}: {}", ch.name, num_words);
           }
@@ -229,7 +228,7 @@ and then add a check to make sure we skip ignored chapters.
 
 ## Output and Signalling Failure
 
-While it's nice to print word counts to the terminal when a book is built, it 
+While it's nice to print word counts to the terminal when a book is built, it
 might also be a good idea to output them to a file somewhere. `mdbook` tells a
 backend where it should place any generated output via the `destination` field
 in [`RenderContext`].
@@ -240,17 +239,17 @@ in [`RenderContext`].
 - use std::io;
   use mdbook::renderer::RenderContext;
   use mdbook::book::{BookItem, Chapter};
-  
+
   fn main() {
     ...
-  
+
 +     let _ = fs::create_dir_all(&ctx.destination);
 +     let mut f = File::create(ctx.destination.join("wordcounts.txt")).unwrap();
-+ 
++
       for item in ctx.book.iter() {
           if let BookItem::Chapter(ref ch) = *item {
               ...
-  
+
               let num_words = count_words(ch);
               println!("{}: {}", ch.name, num_words);
 +             writeln!(f, "{}: {}", ch.name, num_words).unwrap();
@@ -262,9 +261,13 @@ in [`RenderContext`].
 > **Note:** There is no guarantee that the destination directory exists or is
 > empty (`mdbook` may leave the previous contents to let backends do caching),
 > so it's always a good idea to create it with `fs::create_dir_all()`.
+>
+> If the destination directory already exists, don't assume it will be empty.
+> To allow backends to cache the results from previous runs, `mdbook` may leave
+> old content in the directory.
 
 There's always the possibility that an error will occur while processing a book
-(just look at all the `unwrap()`'s we've written already), so `mdbook` will 
+(just look at all the `unwrap()`'s we've written already), so `mdbook` will
 interpret a non-zero exit code as a rendering failure.
 
 For example, if we wanted to make sure all chapters have an *even* number of
@@ -277,11 +280,11 @@ like this:
 
   fn main() {
       ...
-  
+
       for item in ctx.book.iter() {
           if let BookItem::Chapter(ref ch) = *item {
               ...
-  
+
               let num_words = count_words(ch);
               println!("{}: {}", ch.name, num_words);
               writeln!(f, "{}: {}", ch.name, num_words).unwrap();
@@ -304,8 +307,8 @@ like this:
 
 Now, if we reinstall the backend and build a book,
 
-```
-$ cargo install --force
+```shell
+$ cargo install --path . --force
 $ mdbook build /path/to/book
 ...
 2018-01-16 21:21:39 [INFO] (mdbook::renderer): Invoking the "wordcount" renderer
@@ -315,27 +318,27 @@ init: 283
 init has an odd number of words!
 2018-01-16 21:21:39 [ERROR] (mdbook::renderer): Renderer exited with non-zero return code.
 2018-01-16 21:21:39 [ERROR] (mdbook::utils): Error: Rendering failed
-2018-01-16 21:21:39 [ERROR] (mdbook::utils): 	Caused By: The "mdbook-wordcount" renderer failed
+2018-01-16 21:21:39 [ERROR] (mdbook::utils):    Caused By: The "mdbook-wordcount" renderer failed
 ```
 
 As you've probably already noticed, output from the plugin's subprocess is
-immediately passed through to the user. It is encouraged for plugins to
-follow the "rule of silence" and only generate output when necessary (e.g. an
-error in generation or a warning).
+immediately passed through to the user. It is encouraged for plugins to follow
+the "rule of silence" and only generate output when necessary (e.g. an error in
+generation or a warning).
 
-All environment variables are passed through to the backend, allowing you to
-use the usual `RUST_LOG` to control logging verbosity.
+All environment variables are passed through to the backend, allowing you to use
+the usual `RUST_LOG` to control logging verbosity.
 
 
 ## Wrapping Up
 
 Although contrived, hopefully this example was enough to show how you'd create
-an alternate backend for `mdbook`. If you feel it's missing something, don't 
+an alternative backend for `mdbook`. If you feel it's missing something, don't
 hesitate to create an issue in the [issue tracker] so we can improve the user
 guide.
 
 The existing backends mentioned towards the start of this chapter should serve
-as a good example of how it's done in real life, so feel free to skim through 
+as a good example of how it's done in real life, so feel free to skim through
 the source code or ask questions.
 
 
@@ -343,10 +346,10 @@ the source code or ask questions.
 [mdbook-epub]: https://github.com/Michael-F-Bryan/mdbook-epub
 [mdbook-test]: https://github.com/Michael-F-Bryan/mdbook-test
 [rust-skeptic]: https://github.com/budziq/rust-skeptic
-[`RenderContext`]: http://rust-lang-nursery.github.io/mdBook/mdbook/renderer/struct.RenderContext.html
-[`RenderContext::from_json()`]: http://rust-lang-nursery.github.io/mdBook/mdbook/renderer/struct.RenderContext.html#method.from_json
+[`RenderContext`]: https://docs.rs/mdbook/*/mdbook/renderer/struct.RenderContext.html
+[`RenderContext::from_json()`]: https://docs.rs/mdbook/*/mdbook/renderer/struct.RenderContext.html#method.from_json
 [`semver`]: https://crates.io/crates/semver
-[`Book`]: http://rust-lang-nursery.github.io/mdBook/mdbook/book/struct.Book.html
-[`Book::iter()`]: http://rust-lang-nursery.github.io/mdBook/mdbook/book/struct.Book.html#method.iter
-[`Config`]: http://rust-lang-nursery.github.io/mdBook/mdbook/config/struct.Config.html 
+[`Book`]: https://docs.rs/mdbook/*/mdbook/book/struct.Book.html
+[`Book::iter()`]: https://docs.rs/mdbook/*/mdbook/book/struct.Book.html#method.iter
+[`Config`]: https://docs.rs/mdbook/*/mdbook/config/struct.Config.html
 [issue tracker]: https://github.com/rust-lang-nursery/mdBook/issues

book-example/src/for_developers/preprocessors.md

@@ -11,64 +11,79 @@ the book. Possible use cases are:
   mathjax equivalents
 
 
-## Implementing a Preprocessor
+## Hooking Into MDBook
 
-A preprocessor is represented by the `Preprocessor` trait.
+MDBook uses a fairly simple mechanism for discovering third party plugins.
+A new table is added to `book.toml` (e.g. `preprocessor.foo` for the `foo`
+preprocessor) and then `mdbook` will try to invoke the `mdbook-foo` program as
+part of the build process.
 
-```rust
-pub trait Preprocessor {
-    fn name(&self) -> &str;
-    fn run(&self, ctx: &PreprocessorContext, book: &mut Book) -> Result<()>;
-}
+While preprocessors can be hard-coded to specify which backend it should be run
+for (e.g. it doesn't make sense for MathJax to be used for non-HTML renderers)
+with the `preprocessor.foo.renderer` key.
+
+```toml
+[book]
+title = "My Book"
+authors = ["Michael-F-Bryan"]
+
+[preprocessor.foo]
+# The command can also be specified manually
+command = "python3 /path/to/foo.py"
+# Only run the `foo` preprocessor for the HTML and EPUB renderer
+renderer = ["html", "epub"]
 ```
 
-Where the `PreprocessorContext` is defined as
+In typical unix style, all inputs to the plugin will be written to `stdin` as
+JSON and `mdbook` will read from `stdout` if it is expecting output.
+
+The easiest way to get started is by creating your own implementation of the
+`Preprocessor` trait (e.g. in `lib.rs`) and then creating a shell binary which
+translates inputs to the correct `Preprocessor` method. For convenience, there
+is [an example no-op preprocessor] in the `examples/` directory which can easily
+be adapted for other preprocessors.
+
+<details>
+<summary>Example no-op preprocessor</summary>
 
 ```rust
-pub struct PreprocessorContext {
-    pub root: PathBuf,
-    pub config: Config,
-}
+// nop-preprocessors.rs
+
+{{#include ../../../examples/nop-preprocessor.rs}}
 ```
+</details>
 
-## A complete Example
+## Hints For Implementing A Preprocessor
 
-The magic happens within the `run(...)` method of the [`Preprocessor`][preprocessor-docs] trait implementation.
+By pulling in `mdbook` as a library, preprocessors can have access to the
+existing infrastructure for dealing with books.
 
-As direct access to the chapters is not possible, you will probably end up iterating
-them using `for_each_mut(...)`:
+For example, a custom preprocessor could use the
+[`CmdPreprocessor::parse_input()`] function to deserialize the JSON written to
+`stdin`. Then each chapter of the `Book` can be mutated in-place via
+[`Book::for_each_mut()`], and then written to `stdout` with the `serde_json`
+crate.
+
+Chapters can be accessed either directly (by recursively iterating over
+chapters) or via the `Book::for_each_mut()` convenience method.
+
+The `chapter.content` is just a string which happens to be markdown. While it's
+entirely possible to use regular expressions or do a manual find & replace,
+you'll probably want to process the input into something more computer-friendly.
+The [`pulldown-cmark`][pc] crate implements a production-quality event-based
+Markdown parser, with the [`pulldown-cmark-to-cmark`][pctc] allowing you to
+translate events back into markdown text.
+
+The following code block shows how to remove all emphasis from markdown,
+without accidentally breaking the document.
 
 ```rust
-book.for_each_mut(|item: &mut BookItem| {
-    if let BookItem::Chapter(ref mut chapter) = *item {
-      eprintln!("{}: processing chapter '{}'", self.name(), chapter.name);
-      res = Some(
-          match Deemphasize::remove_emphasis(&mut num_removed_items, chapter) {
-              Ok(md) => {
-                  chapter.content = md;
-                  Ok(())
-              }
-              Err(err) => Err(err),
-          },
-      );
-  }
-});
-```
-
-The `chapter.content` is just a markdown formatted string, and you will have to
-process it in some way. Even though it's entirely possible to implement some sort of
-manual find & replace operation, if that feels too unsafe you can use [`pulldown-cmark`][pc]
-to parse the string into events and work on them instead.
-
-Finally you can use [`pulldown-cmark-to-cmark`][pctc] to transform these events back to
-a string.
-
-The following code block shows how to remove all emphasis from markdown, and do so
-safely.
-
-```rust
-fn remove_emphasis(num_removed_items: &mut i32, chapter: &mut Chapter) -> Result<String> {
+fn remove_emphasis(
+    num_removed_items: &mut usize,
+    chapter: &mut Chapter,
+) -> Result<String> {
     let mut buf = String::with_capacity(chapter.content.len());
+
     let events = Parser::new(&chapter.content).filter(|e| {
         let should_keep = match *e {
             Event::Start(Tag::Emphasis)
@@ -82,15 +97,19 @@ fn remove_emphasis(num_removed_items: &mut i32, chapter: &mut Chapter) -> Result
         }
         should_keep
     });
-    cmark(events, &mut buf, None)
-        .map(|_| buf)
-        .map_err(|err| Error::from(format!("Markdown serialization failed: {}", err)))
+
+    cmark(events, &mut buf, None).map(|_| buf).map_err(|err| {
+        Error::from(format!("Markdown serialization failed: {}", err))
+    })
 }
 ```
 
 For everything else, have a look [at the complete example][example].
 
-[preprocessor-docs]: https://docs.rs/mdbook/0.1.3/mdbook/preprocess/trait.Preprocessor.html
+[preprocessor-docs]: https://docs.rs/mdbook/latest/mdbook/preprocess/trait.Preprocessor.html
 [pc]: https://crates.io/crates/pulldown-cmark
 [pctc]: https://crates.io/crates/pulldown-cmark-to-cmark
-[example]: https://github.com/rust-lang-nursery/mdBook/blob/master/examples/de-emphasize.rs
+[example]: https://github.com/rust-lang-nursery/mdBook/blob/master/examples/nop-preprocessor.rs
+[an example no-op preprocessor]: https://github.com/rust-lang-nursery/mdBook/blob/master/examples/nop-preprocessor.rs
+[`CmdPreprocessor::parse_input()`]: https://docs.rs/mdbook/latest/mdbook/preprocess/trait.Preprocessor.html#method.parse_input
+[`Book::for_each_mut()`]: https://docs.rs/mdbook/latest/mdbook/book/struct.Book.html#method.for_each_mut

book-example/src/format/config.md

@@ -14,6 +14,10 @@ description = "The example book covers examples."
 build-dir = "my-example-book"
 create-missing = false
 
+[preprocessor.index]
+
+[preprocessor.links]
+
 [output.html]
 additional-css = ["custom.css"]
 
@@ -23,9 +27,9 @@ limit-results = 15
 
 ## Supported configuration options
 
-It is important to note that **any** relative path specified in the in the configuration will
-always be taken relative from the root of the book where the configuration file is located.
-
+It is important to note that **any** relative path specified in the
+configuration will always be taken relative from the root of the book where the
+configuration file is located.
 
 ### General metadata
 
@@ -38,6 +42,7 @@ This is general information about your book.
 - **src:** By default, the source directory is found in the directory named
   `src` directly under the root folder. But this is configurable with the `src`
   key in the configuration file.
+- **language:** The main language of the book, which is used as a language attribute `<html lang="en">` for example.
 
 **book.toml**
 ```toml
@@ -46,6 +51,7 @@ title = "Example book"
 authors = ["John Doe", "Jane Doe"]
 description = "The example book covers examples."
 src = "my-src"  # the source files will be found in `root/my-src` instead of `root/src`
+language = "en"
 ```
 
 ### Build options
@@ -58,13 +64,28 @@ This controls the build process of your book.
   will be created when the book is built (i.e. `create-missing = true`). If this
   is `false` then the build process will instead exit with an error if any files
   do not exist.
-- **preprocess:** Specify which preprocessors to be applied. Default is `["links", "index"]`. To disable default preprocessors, pass an empty array `[]` in.
+- **use-default-preprocessors:** Disable the default preprocessors of (`links` &
+  `index`) by setting this option to `false`.
 
+  If you have the same, and/or other preprocessors declared via their table
+  of configuration, they will run instead.
+
+  - For clarity, with no preprocessor configuration, the default `links` and
+    `index` will run.
+  - Setting `use-default-preprocessors = false` will disable these
+    default preprocessors from running.
+  - Adding `[preprocessor.links]`, for example, will ensure, regardless of
+    `use-default-preprocessors` that `links` it will run.
+
+## Configuring Preprocessors
 
 The following preprocessors are available and included by default:
 
-- `links`: Expand the `{{# playpen}}` and `{{# include}}` handlebars helpers in a chapter.
-- `index`: Convert all chapter files named `README.md` into `index.md`. That is to say, all `README.md` would be rendered to an index file `index.html` in the rendered book.
+- `links`: Expand the `{{ #playpen }}`, `{{ #include }}`, and `{{ #rustdoc_include }}` handlebars
+  helpers in a chapter to include the contents of a file.
+- `index`: Convert all chapter files named `README.md` into `index.md`. That is
+  to say, all `README.md` would be rendered to an index file `index.html` in the
+  rendered book.
 
 
 **book.toml**
@@ -72,94 +93,164 @@ The following preprocessors are available and included by default:
 [build]
 build-dir = "build"
 create-missing = false
-preprocess = ["links", "index"]
+
+[preprocessor.links]
+
+[preprocessor.index]
 ```
 
+### Custom Preprocessor Configuration
+
+Like renderers, preprocessor will need to be given its own table (e.g.
+`[preprocessor.mathjax]`). In the section, you may then pass extra
+configuration to the preprocessor by adding key-value pairs to the table.
+
+For example
+
+```toml
+[preprocessor.links]
+# set the renderers this preprocessor will run for
+renderers = ["html"]
+some_extra_feature = true
+```
+
+#### Locking a Preprocessor dependency to a renderer
+
+You can explicitly specify that a preprocessor should run for a renderer by
+binding the two together.
+
+```toml
+[preprocessor.mathjax]
+renderers = ["html"]  # mathjax only makes sense with the HTML renderer
+```
+
+### Provide Your Own Command
+
+By default when you add a `[preprocessor.foo]` table to your `book.toml` file,
+`mdbook` will try to invoke the `mdbook-foo` executable. If you want to use a
+different program name or pass in command-line arguments, this behaviour can
+be overridden by adding a `command` field.
+
+```toml
+[preprocessor.random]
+command = "python random.py"
+```
+
+## Configuring Renderers
+
 ### HTML renderer options
+
 The HTML renderer has a couple of options as well. All the options for the
 renderer need to be specified under the TOML table `[output.html]`.
 
 The following configuration options are available:
 
-- **theme:** mdBook comes with a default theme and all the resource files
-  needed for it. But if this option is set, mdBook will selectively overwrite
-  the theme files with the ones found in the specified folder.
-- **curly-quotes:** Convert straight quotes to curly quotes, except for
-  those that occur in code blocks and code spans. Defaults to `false`.
-- **google-analytics:** If you use Google Analytics, this option lets you
-  enable it by simply specifying your ID in the configuration file.
-- **additional-css:** If you need to slightly change the appearance of your
-  book without overwriting the whole style, you can specify a set of
-  stylesheets that will be loaded after the default ones where you can
-  surgically change the style.
+- **theme:** mdBook comes with a default theme and all the resource files needed
+  for it. But if this option is set, mdBook will selectively overwrite the theme
+  files with the ones found in the specified folder.
+- **default-theme:** The theme color scheme to select by default in the
+  'Change Theme' dropdown. Defaults to `light`.
+- **preferred-dark-theme:** The default dark theme. This theme will be used if
+  the browser requests the dark version of the site via the
+  ['prefers-color-scheme'](https://developer.mozilla.org/en-US/docs/Web/CSS/@media/prefers-color-scheme)
+  CSS media query. Defaults to the same theme as `default-theme`.
+- **curly-quotes:** Convert straight quotes to curly quotes, except for those
+  that occur in code blocks and code spans. Defaults to `false`.
+- **mathjax-support:** Adds support for [MathJax](mathjax.md). Defaults to
+  `false`.
+- **google-analytics:** If you use Google Analytics, this option lets you enable
+  it by simply specifying your ID in the configuration file.
+- **additional-css:** If you need to slightly change the appearance of your book
+  without overwriting the whole style, you can specify a set of stylesheets that
+  will be loaded after the default ones where you can surgically change the
+  style.
 - **additional-js:** If you need to add some behaviour to your book without
-  removing the current behaviour, you can specify a set of JavaScript files
-  that will be loaded alongside the default one.
+  removing the current behaviour, you can specify a set of JavaScript files that
+  will be loaded alongside the default one.
 - **no-section-label:** mdBook by defaults adds section label in table of
-  contents column. For example, "1.", "2.1". Set this option to true to
-  disable those labels. Defaults to `false`.
+  contents column. For example, "1.", "2.1". Set this option to true to disable
+  those labels. Defaults to `false`.
+- **fold:** A subtable for configuring sidebar section-folding behavior.
 - **playpen:** A subtable for configuring various playpen settings.
-- **search:** A subtable for configuring the in-browser search
-  functionality. mdBook must be compiled with the `search` feature enabled
-  (on by default).
+- **search:** A subtable for configuring the in-browser search functionality.
+  mdBook must be compiled with the `search` feature enabled (on by default).
+- **git-repository-url:**  A url to the git repository for the book. If provided
+  an icon link will be output in the menu bar of the book.
+- **git-repository-icon:** The FontAwesome icon class to use for the git
+  repository link. Defaults to `fa-github`.
+  
+Available configuration options for the `[output.html.fold]` table:
+
+- **enable:** Enable section-folding. When off, all folds are open.
+  Defaults to `false`.
+- **level:** The higher the more folded regions are open. When level is 0, all
+  folds are closed. Defaults to `0`.
 
 Available configuration options for the `[output.html.playpen]` table:
 
 - **editable:** Allow editing the source code. Defaults to `false`.
+- **copyable:** Display the copy button on code snippets. Defaults to `true`.
 - **copy-js:** Copy JavaScript files for the editor to the output directory.
   Defaults to `true`.
+- **line-numbers** Display line numbers on editable sections of code. Requires both `editable` and `copy-js` to be `true`. Defaults to `false`.
 
 [Ace]: https://ace.c9.io/
 
 Available configuration options for the `[output.html.search]` table:
 
+- **enable:** Enables the search feature. Defaults to `true`.
 - **limit-results:** The maximum number of search results. Defaults to `30`.
-- **teaser-word-count:** The number of words used for a search result teaser. 
+- **teaser-word-count:** The number of words used for a search result teaser.
   Defaults to `30`.
-- **use-boolean-and:** Define the logical link between multiple search words. 
-  If true, all search words must appear in each result. Defaults to `true`.
+- **use-boolean-and:** Define the logical link between multiple search words. If
+  true, all search words must appear in each result. Defaults to `false`.
 - **boost-title:** Boost factor for the search result score if a search word
   appears in the header. Defaults to `2`.
-- **boost-hierarchy:** Boost factor for the search result score if a search
-  word appears in the hierarchy. The hierarchy contains all titles of the
-  parent documents and all parent headings. Defaults to `1`.
-- **boost-paragraph:** Boost factor for the search result score if a search 
-  word appears in the text. Defaults to `1`.
-- **expand:** True if search should match longer results e.g. search `micro` 
+- **boost-hierarchy:** Boost factor for the search result score if a search word
+  appears in the hierarchy. The hierarchy contains all titles of the parent
+  documents and all parent headings. Defaults to `1`.
+- **boost-paragraph:** Boost factor for the search result score if a search word
+  appears in the text. Defaults to `1`.
+- **expand:** True if search should match longer results e.g. search `micro`
   should match `microwave`. Defaults to `true`.
 - **heading-split-level:** Search results will link to a section of the document
-  which contains the result. Documents are split into sections by headings
-  this level or less.
-  Defaults to `3`. (`### This is a level 3 heading`)
-- **copy-js:** Copy JavaScript files for the search implementation to the
-  output directory. Defaults to `true`.
+  which contains the result. Documents are split into sections by headings this
+  level or less. Defaults to `3`. (`### This is a level 3 heading`)
+- **copy-js:** Copy JavaScript files for the search implementation to the output
+  directory. Defaults to `true`.
+
+This shows all available HTML output options in the **book.toml**:
 
-This shows all available options in the **book.toml**:
 ```toml
 [book]
 title = "Example book"
 authors = ["John Doe", "Jane Doe"]
 description = "The example book covers examples."
 
-[build]
-build-dir = "book"
-create-missing = true
-preprocess = ["links", "index"]
-
 [output.html]
 theme = "my-theme"
+default-theme = "light"
+preferred-dark-theme = "navy"
 curly-quotes = true
+mathjax-support = false
 google-analytics = "123456"
 additional-css = ["custom.css", "custom2.css"]
 additional-js = ["custom.js"]
+no-section-label = false
+git-repository-url = "https://github.com/rust-lang-nursery/mdBook"
+git-repository-icon = "fa-github"
+
+[output.html.fold]
+enable = false
+level = 0
 
 [output.html.playpen]
-editor = "./path/to/editor"
 editable = false
+copy-js = true
+line-numbers = false
 
 [output.html.search]
 enable = true
-searcher = "./path/to/searcher"
 limit-results = 30
 teaser-word-count = 30
 use-boolean-and = true
@@ -168,8 +259,39 @@ boost-hierarchy = 1
 boost-paragraph = 1
 expand = true
 heading-split-level = 3
+copy-js = true
 ```
 
+### Markdown Renderer
+
+The Markdown renderer will run preprocessors and then output the resulting
+Markdown. This is mostly useful for debugging preprocessors, especially in
+conjunction with `mdbook test` to see the Markdown that `mdbook` is passing
+to `rustdoc`.
+
+The Markdown renderer is included with `mdbook` but disabled by default.
+Enable it by adding an emtpy table to your `book.toml` as follows:
+
+```toml
+[output.markdown]
+```
+
+There are no configuration options for the Markdown renderer at this time;
+only whether it is enabled or disabled.
+
+See [the preprocessors documentation](#configuring-preprocessors) for how to
+specify which preprocessors should run before the Markdown renderer.
+
+### Custom Renderers
+
+A custom renderer can be enabled by adding a `[output.foo]` table to your
+`book.toml`. Similar to [preprocessors](#configuring-preprocessors) this will
+instruct `mdbook` to pass a representation of the book to `mdbook-foo` for
+rendering.
+
+Custom renderers will have access to all configuration within their table
+(i.e. anything under `[output.foo]`), and the command to be invoked can be
+manually specified with the `command` field.
 
 ## Environment Variables
 
@@ -178,10 +300,10 @@ corresponding environment variable. Because many operating systems restrict
 environment variables to be alphanumeric characters or `_`, the configuration
 key needs to be formatted slightly differently to the normal `foo.bar.baz` form.
 
-Variables starting with `MDBOOK_` are used for configuration. The key is
-created by removing the `MDBOOK_` prefix and turning the resulting
-string into `kebab-case`. Double underscores (`__`) separate nested
-keys, while a single underscore (`_`) is replaced with a dash (`-`).
+Variables starting with `MDBOOK_` are used for configuration. The key is created
+by removing the `MDBOOK_` prefix and turning the resulting string into
+`kebab-case`. Double underscores (`__`) separate nested keys, while a single
+underscore (`_`) is replaced with a dash (`-`).
 
 For example:
 
@@ -191,21 +313,21 @@ For example:
 - `MDBOOK_FOO_BAR` -> `foo-bar`
 - `MDBOOK_FOO_bar__baz` -> `foo-bar.baz`
 
-So by setting the `MDBOOK_BOOK__TITLE` environment variable you can
-override the book's title without needing to touch your `book.toml`.
+So by setting the `MDBOOK_BOOK__TITLE` environment variable you can override the
+book's title without needing to touch your `book.toml`.
 
-> **Note:** To facilitate setting more complex config items, the value
-> of an environment variable is first parsed as JSON, falling back to a
-> string if the parse fails.
+> **Note:** To facilitate setting more complex config items, the value of an
+> environment variable is first parsed as JSON, falling back to a string if the
+> parse fails.
 >
-> This means, if you so desired, you could override all book metadata
-> when building the book with something like
+> This means, if you so desired, you could override all book metadata when
+> building the book with something like
 >
-> ```text
+> ```shell
 > $ export MDBOOK_BOOK="{'title': 'My Awesome Book', authors: ['Michael-F-Bryan']}"
 > $ mdbook build
 > ```
 
-The latter case may be useful in situations where `mdbook` is invoked
-from a script or CI, where it sometimes isn't possible to update the
-`book.toml` before building.
+The latter case may be useful in situations where `mdbook` is invoked from a
+script or CI, where it sometimes isn't possible to update the `book.toml` before
+building.

book-example/src/format/mathjax.md

@@ -1,29 +1,37 @@
 # MathJax Support
 
-mdBook has optional support for math equations through [MathJax](https://www.mathjax.org/).
+mdBook has optional support for math equations through
+[MathJax](https://www.mathjax.org/).
 
-To enable MathJax, you need to add the `mathjax-support` key to your `book.toml` under the `output.html` section.
+To enable MathJax, you need to add the `mathjax-support` key to your `book.toml`
+under the `output.html` section.
 
 ```toml
 [output.html]
 mathjax-support = true
 ```
 
->**Note:**
-The usual delimiters MathJax uses are not yet supported. You can't currently use `$$ ... $$` as delimiters and the `\[ ... \]` delimiters need an extra backslash to work. Hopefully this limitation will be lifted soon.
+>**Note:** The usual delimiters MathJax uses are not yet supported. You can't
+currently use `$$ ... $$` as delimiters and the `\[ ... \]` delimiters need an
+extra backslash to work. Hopefully this limitation will be lifted soon.
 
->**Note:**
-> When you use double backslashes in MathJax blocks (for example in commands such as `\begin{cases} \frac 1 2 \\ \frac 3 4 \end{cases}`) you need to add _two extra_ backslashes (e.g., `\begin{cases} \frac 1 2 \\\\ \frac 3 4 \end{cases}`).
+>**Note:** When you use double backslashes in MathJax blocks (for example in
+> commands such as `\begin{cases} \frac 1 2 \\ \frac 3 4 \end{cases}`) you need
+> to add _two extra_ backslashes (e.g., `\begin{cases} \frac 1 2 \\\\ \frac 3 4
+> \end{cases}`).
 
 
 ### Inline equations
-Inline equations are delimited by `\\(` and `\\)`. So for example, to render the following inline equation \\( \int x dx = \frac{x^2}{2} + C \\) you would write the following:
+Inline equations are delimited by `\\(` and `\\)`. So for example, to render the
+following inline equation \\( \int x dx = \frac{x^2}{2} + C \\) you would write
+the following:
 ```
 \\( \int x dx = \frac{x^2}{2} + C \\)
 ```
 
 ### Block equations
-Block equations are delimited by `\\[` and `\\]`. To render the following equation
+Block equations are delimited by `\\[` and `\\]`. To render the following
+equation
 
 \\[ \mu = \frac{1}{N} \sum_{i=0} x_i \\]
 

book-example/src/format/mdbook.md

@@ -2,7 +2,10 @@
 
 ## Hiding code lines
 
-There is a feature in mdBook that lets you hide code lines by prepending them with a `#`.
+There is a feature in mdBook that lets you hide code lines by prepending them
+with a `#` [in the same way that Rustdoc does][rustdoc-hide].
+
+[rustdoc-hide]: https://doc.rust-lang.org/stable/rustdoc/documentation-tests.html#hiding-portions-of-the-example
 
 ```bash
 # fn main() {
@@ -34,7 +37,20 @@ With the following syntax, you can include files into your book:
 
 The path to the file has to be relative from the current source file.
 
-Usually, this command is used for including code snippets and examples. In this case, oftens one would include a specific part of the file e.g. which only contains the relevant lines for the example. We support four different modes of partial includes:
+mdBook will interpret included files as markdown. Since the include command
+is usually used for inserting code snippets and examples, you will often
+wrap the command with ```` ``` ```` to display the file contents without
+interpretting them.
+
+````hbs
+```
+\{{#include file.rs}}
+```
+````
+
+## Including portions of a file
+Often you only need a specific part of the file e.g. relevant lines for an
+example. We support four different modes of partial includes:
 
 ```hbs
 \{{#include file.rs:2}}
@@ -43,7 +59,119 @@ Usually, this command is used for including code snippets and examples. In this
 \{{#include file.rs:2:10}}
 ```
 
-The first command only includes the second line from file `file.rs`. The second command includes all lines up to line 10, i.e. the lines from 11 till the end of the file are omitted. The third command includes all lines from line 2, i.e. the first line is omitted. The last command includes the excerpt of `file.rs` consisting of lines 2 to 10.
+The first command only includes the second line from file `file.rs`. The second
+command includes all lines up to line 10, i.e. the lines from 11 till the end of
+the file are omitted. The third command includes all lines from line 2, i.e. the
+first line is omitted. The last command includes the excerpt of `file.rs`
+consisting of lines 2 to 10.
+
+To avoid breaking your book when modifying included files, you can also
+include a specific section using anchors instead of line numbers.
+An anchor is a pair of matching lines. The line beginning an anchor must
+match the regex "ANCHOR:\s*[\w_-]+" and similarly the ending line must match
+the regex "ANCHOR_END:\s*[\w_-]+". This allows you to put anchors in
+any kind of commented line.
+
+Consider the following file to include:
+```rs
+/* ANCHOR: all */
+
+// ANCHOR: component
+struct Paddle {
+    hello: f32,
+}
+// ANCHOR_END: component
+
+////////// ANCHOR: system
+impl System for MySystem { ... }
+////////// ANCHOR_END: system
+
+/* ANCHOR_END: all */
+```
+
+Then in the book, all you have to do is:
+````hbs
+Here is a component:
+```rust,no_run,noplaypen
+\{{#include file.rs:component}}
+```
+
+Here is a system:
+```rust,no_run,noplaypen
+\{{#include file.rs:system}}
+```
+
+This is the full file.
+```rust,no_run,noplaypen
+\{{#include file.rs:all}}
+```
+````
+
+Lines containing anchor patterns inside the included anchor are ignored.
+
+## Including a file but initially hiding all except specified lines
+
+The `rustdoc_include` helper is for including code from external Rust files that contain complete
+examples, but only initially showing particular lines specified with line numbers or anchors in the
+same way as with `include`.
+
+The lines not in the line number range or between the anchors will still be included, but they will
+be prefaced with `#`. This way, a reader can expand the snippet to see the complete example, and
+Rustdoc will use the complete example when you run `mdbook test`.
+
+For example, consider a file named `file.rs` that contains this Rust program:
+
+```rust
+fn main() {
+    let x = add_one(2);
+    assert_eq!(x, 3);
+}
+
+fn add_one(num: i32) -> i32 {
+    num + 1
+}
+```
+
+We can include a snippet that initially shows only line 2 by using this syntax:
+
+````hbs
+To call the `add_one` function, we pass it an `i32` and bind the returned value to `x`:
+
+```rust
+\{{#rustdoc_include file.rs:2}}
+```
+````
+
+This would have the same effect as if we had manually inserted the code and hidden all but line 2
+using `#`:
+
+````hbs
+To call the `add_one` function, we pass it an `i32` and bind the returned value to `x`:
+
+```rust
+# fn main() {
+    let x = add_one(2);
+#     assert_eq!(x, 3);
+# }
+#
+# fn add_one(num: i32) -> i32 {
+#     num + 1
+#}
+```
+````
+
+That is, it looks like this (click the "expand" icon to see the rest of the file):
+
+```rust
+# fn main() {
+    let x = add_one(2);
+#     assert_eq!(x, 3);
+# }
+#
+# fn add_one(num: i32) -> i32 {
+#     num + 1
+#}
+```
 
 ## Inserting runnable Rust files
 
@@ -55,7 +183,9 @@ With the following syntax, you can insert runnable Rust files into your book:
 
 The path to the Rust file has to be relative from the current source file.
 
-When play is clicked, the code snippet will be sent to the [Rust Playpen] to be compiled and run. The result is sent back and displayed directly underneath the code.
+When play is clicked, the code snippet will be sent to the [Rust Playpen] to be
+compiled and run. The result is sent back and displayed directly underneath the
+code.
 
 Here is what a rendered code snippet looks like:
 

book-example/src/format/summary.md

@@ -1,32 +1,38 @@
 # SUMMARY.md
 
-The summary file is used by mdBook to know what chapters to include,
-in what order they should appear, what their hierarchy is and where the source files are.
-Without this file, there is no book.
+The summary file is used by mdBook to know what chapters to include, in what
+order they should appear, what their hierarchy is and where the source files
+are. Without this file, there is no book.
 
 Even though `SUMMARY.md` is a markdown file, the formatting is very strict to
 allow for easy parsing. Let's see how you should format your `SUMMARY.md` file.
 
 #### Allowed elements
 
-1. ***Title*** It's common practice to begin with a title, generally
-   <code class="language-markdown"># Summary</code>.
-   But it is not mandatory, the parser just ignores it. So you can too
-   if you feel like it.
+1. ***Title*** It's common practice to begin with a title, generally <code
+   class="language-markdown"># Summary</code>. But it is not mandatory, the
+   parser just ignores it. So you can too if you feel like it.
 
-2. ***Prefix Chapter*** Before the main numbered chapters you can add a couple of elements that will not be numbered. This is useful for
-   forewords, introductions, etc. There are however some constraints. You can not nest prefix chapters, they should all be on the root level. And you can not add prefix chapters once you have added numbered chapters.
+2. ***Prefix Chapter*** Before the main numbered chapters you can add a couple
+   of elements that will not be numbered. This is useful for forewords,
+   introductions, etc. There are however some constraints. You can not nest
+   prefix chapters, they should all be on the root level. And you can not add
+   prefix chapters once you have added numbered chapters.
    ```markdown
    [Title of prefix element](relative/path/to/markdown.md)
    ```
 
-3. ***Numbered Chapter*** Numbered chapters are the main content of the book, they will be numbered and can be nested,
-   resulting in a nice hierarchy (chapters, sub-chapters, etc.)
+3. ***Numbered Chapter*** Numbered chapters are the main content of the book,
+   they will be numbered and can be nested, resulting in a nice hierarchy
+   (chapters, sub-chapters, etc.)
    ```markdown
    - [Title of the Chapter](relative/path/to/markdown.md)
    ```
    You can either use `-` or `*` to indicate a numbered chapter.
 
-4. ***Suffix Chapter*** After the numbered chapters you can add a couple of non-numbered chapters. They are the same as prefix chapters but come after the numbered chapters instead of before.
+4. ***Suffix Chapter*** After the numbered chapters you can add a couple of
+   non-numbered chapters. They are the same as prefix chapters but come after
+   the numbered chapters instead of before.
 
-All other elements are unsupported and will be ignored at best or result in an error.
+All other elements are unsupported and will be ignored at best or result in an
+error.

book-example/src/format/theme/README.md

@@ -1,22 +1,34 @@
 # Theme
 
-The default renderer uses a [handlebars](http://handlebarsjs.com/) template to render your markdown files and comes with a default theme
-included in the mdBook binary.
+The default renderer uses a [handlebars](http://handlebarsjs.com/) template to
+render your markdown files and comes with a default theme included in the mdBook
+binary.
 
-The theme is totally customizable, you can selectively replace every file from the theme by your own by adding a
-`theme` directory next to `src` folder in your project root. Create a new file with the name of the file you want to override
+The theme is totally customizable, you can selectively replace every file from
+the theme by your own by adding a `theme` directory next to `src` folder in your
+project root. Create a new file with the name of the file you want to override
 and now that file will be used instead of the default file.
 
 Here are the files you can override:
 
 - ***index.hbs*** is the handlebars template.
-- ***book.css*** is the style used in the output. If you want to change the design of your book, this is probably the file you want to modify. Sometimes in conjunction with `index.hbs` when you want to radically change the layout.
-- ***book.js*** is mostly used to add client side functionality, like hiding / un-hiding the sidebar, changing the theme, ...
-- ***highlight.js*** is the JavaScript that is used to highlight code snippets, you should not need to modify this.  
+- ***book.css*** is the style used in the output. If you want to change the
+  design of your book, this is probably the file you want to modify. Sometimes
+  in conjunction with `index.hbs` when you want to radically change the layout.
+- ***book.js*** is mostly used to add client side functionality, like hiding /
+  un-hiding the sidebar, changing the theme, ...
+- ***highlight.js*** is the JavaScript that is used to highlight code snippets,
+  you should not need to modify this.  
 - ***highlight.css*** is the theme used for the code highlighting
 - ***favicon.png*** the favicon that will be used
 
-Generally, when you want to tweak the theme, you don't need to override all the files. If you only need changes in the stylesheet,
-there is no point in overriding all the other files. Because custom files take precedence over built-in ones, they will not get updated with new fixes / features.
+Generally, when you want to tweak the theme, you don't need to override all the
+files. If you only need changes in the stylesheet, there is no point in
+overriding all the other files. Because custom files take precedence over
+built-in ones, they will not get updated with new fixes / features.
 
-**Note:** When you override a file, it is possible that you break some functionality. Therefore I recommend to use the file from the default theme as template and only add / modify what you need. You can copy the default theme into your source directory automatically by using `mdbook init --theme` just remove the files you don't want to override.
+**Note:** When you override a file, it is possible that you break some
+functionality. Therefore I recommend to use the file from the default theme as
+template and only add / modify what you need. You can copy the default theme
+into your source directory automatically by using `mdbook init --theme` just
+remove the files you don't want to override.

book-example/src/format/theme/editor.md

@@ -1,13 +1,16 @@
 # Editor
 
-In addition to providing runnable code playpens, mdBook optionally allows them to be editable. In order to enable editable code blocks, the following needs to be added to the ***book.toml***:
+In addition to providing runnable code playpens, mdBook optionally allows them
+to be editable. In order to enable editable code blocks, the following needs to
+be added to the ***book.toml***:
 
 ```toml
 [output.html.playpen]
 editable = true
 ```
 
-To make a specific block available for editing, the attribute `editable` needs to be added to it:
+To make a specific block available for editing, the attribute `editable` needs
+to be added to it:
 
 <pre><code class="language-markdown">```rust,editable
 fn main() {
@@ -29,7 +32,8 @@ Note the new `Undo Changes` button in the editable playpens.
 
 ## Customizing the Editor
 
-By default, the editor is the [Ace](https://ace.c9.io/) editor, but, if desired, the functionality may be overriden by providing a different folder:
+By default, the editor is the [Ace](https://ace.c9.io/) editor, but, if desired,
+the functionality may be overriden by providing a different folder:
 
 ```toml
 [output.html.playpen]
@@ -37,4 +41,6 @@ editable = true
 editor = "/path/to/editor"
 ```
 
-Note that for the editor changes to function correctly, the `book.js` inside of the `theme` folder will need to be overriden as it has some couplings with the default Ace editor.
+Note that for the editor changes to function correctly, the `book.js` inside of
+the `theme` folder will need to be overriden as it has some couplings with the
+default Ace editor.

book-example/src/format/theme/index-hbs.md

@@ -1,15 +1,15 @@
 # index.hbs
 
-`index.hbs` is the handlebars template that is used to render the book.
-The markdown files are processed to html and then injected in that template.
+`index.hbs` is the handlebars template that is used to render the book. The
+markdown files are processed to html and then injected in that template.
 
-If you want to change the layout or style of your book, chances are that you will
-have to modify this template a little bit. Here is what you need to know.
+If you want to change the layout or style of your book, chances are that you
+will have to modify this template a little bit. Here is what you need to know.
 
 ## Data
 
-A lot of data is exposed to the handlebars template with the "context".
-In the handlebars template you can access this information by using
+A lot of data is exposed to the handlebars template with the "context". In the
+handlebars template you can access this information by using
 
 ```handlebars
 {{name_of_property}}
@@ -17,75 +17,84 @@ In the handlebars template you can access this information by using
 
 Here is a list of the properties that are exposed:
 
-- ***language*** Language of the book in the form `en`. To use in <code class="language-html">\<html lang="{{ language }}"></code> for example.
-At the moment it is hardcoded.
+- ***language*** Language of the book in the form `en`, as specified in `book.toml` (if not specified, defaults to `en`). To use in <code
+  class="language-html">\<html lang="{{ language }}"></code> for example.
 - ***title*** Title of the book, as specified in `book.toml`
 - ***chapter_title*** Title of the current chapter, as listed in `SUMMARY.md`
 
-- ***path*** Relative path to the original markdown file from the source directory
+- ***path*** Relative path to the original markdown file from the source
+  directory
 - ***content*** This is the rendered markdown.
-- ***path_to_root*** This is a path containing exclusively `../`'s that points to the root of the book from the current file.
-Since the original directory structure is maintained, it is useful to prepend relative links with this `path_to_root`.
+- ***path_to_root*** This is a path containing exclusively `../`'s that points
+  to the root of the book from the current file. Since the original directory
+  structure is maintained, it is useful to prepend relative links with this
+  `path_to_root`.
 
 - ***chapters*** Is an array of dictionaries of the form
   ```json
   {"section": "1.2.1", "name": "name of this chapter", "path": "dir/markdown.md"}
   ```
-  containing all the chapters of the book. It is used for example to construct the table of contents (sidebar).
+  containing all the chapters of the book. It is used for example to construct
+  the table of contents (sidebar).
 
 ## Handlebars Helpers
 
-In addition to the properties you can access, there are some handlebars helpers at your disposal.
+In addition to the properties you can access, there are some handlebars helpers
+at your disposal.
 
-1.  ### toc
+### 1. toc
 
-    The toc helper is used like this
+The toc helper is used like this
 
-    ```handlebars
-    {{#toc}}{{/toc}}
-    ```
+```handlebars
+{{#toc}}{{/toc}}
+```
 
-    and outputs something that looks like this, depending on the structure of your book
+and outputs something that looks like this, depending on the structure of your
+book
 
-    ```html
-    <ul class="chapter">
-        <li><a href="link/to/file.html">Some chapter</a></li>
-        <li>
-            <ul class="section">
-                <li><a href="link/to/other_file.html">Some other Chapter</a></li>
-            </ul>
-        </li>
-    </ul>
-    ```
+```html
+<ul class="chapter">
+    <li><a href="link/to/file.html">Some chapter</a></li>
+    <li>
+        <ul class="section">
+            <li><a href="link/to/other_file.html">Some other Chapter</a></li>
+        </ul>
+    </li>
+</ul>
+```
 
-    If you would like to make a toc with another structure, you have access to the chapters property containing all the data.
-    The only limitation at the moment is that you would have to do it with JavaScript instead of with a handlebars helper.
+If you would like to make a toc with another structure, you have access to the
+chapters property containing all the data. The only limitation at the moment
+is that you would have to do it with JavaScript instead of with a handlebars
+helper.
 
-    ```html
-    <script>
-    var chapters = {{chapters}};
-    // Processing here
-    </script>
-    ```
+```html
+<script>
+var chapters = {{chapters}};
+// Processing here
+</script>
+```
 
-2.  ### previous / next
+### 2. previous / next
 
-    The previous and next helpers expose a `link` and `name` property to the previous and next chapters.
+The previous and next helpers expose a `link` and `name` property to the
+previous and next chapters.
 
-    They are used like this
+They are used like this
 
-    ```handlebars
-    {{#previous}}
-        <a href="{{link}}" class="nav-chapters previous">
-            <i class="fa fa-angle-left"></i>
-        </a>
-    {{/previous}}
-    ```
+```handlebars
+{{#previous}}
+    <a href="{{link}}" class="nav-chapters previous">
+        <i class="fa fa-angle-left"></i>
+    </a>
+{{/previous}}
+```
 
-    The inner html will only be rendered if the previous / next chapter exists.
-    Of course the inner html can be changed to your liking.
+The inner html will only be rendered if the previous / next chapter exists.
+Of course the inner html can be changed to your liking.
 
 ------
 
-*If you would like me to expose other properties or helpers, please [create a new issue](https://github.com/rust-lang-nursery/mdBook/issues)
-and I will consider it.*
+*If you would like other properties or helpers exposed, please [create a new
+issue](https://github.com/rust-lang-nursery/mdBook/issues)*

book-example/src/format/theme/syntax-highlighting.md

@@ -1,6 +1,7 @@
 # Syntax Highlighting
 
-For syntax highlighting I use [Highlight.js](https://highlightjs.org) with a custom theme.
+For syntax highlighting I use [Highlight.js](https://highlightjs.org) with a
+custom theme.
 
 Automatic language detection has been turned off, so you will probably want to
 specify the programming language you use like this
@@ -12,19 +13,23 @@ fn main() {
 ```</code></pre>
 
 ## Custom theme
-Like the rest of the theme, the files used for syntax highlighting can be overridden with your own.
+Like the rest of the theme, the files used for syntax highlighting can be
+overridden with your own.
 
-- ***highlight.js*** normally you shouldn't have to overwrite this file, unless you want to use a more recent version.
+- ***highlight.js*** normally you shouldn't have to overwrite this file, unless
+  you want to use a more recent version.
 - ***highlight.css*** theme used by highlight.js for syntax highlighting.
 
-If you want to use another theme for `highlight.js` download it from their website, or make it yourself,
-rename it to `highlight.css` and put it in `src/theme` (or the equivalent if you changed your source folder)
+If you want to use another theme for `highlight.js` download it from their
+website, or make it yourself, rename it to `highlight.css` and put it in
+`src/theme` (or the equivalent if you changed your source folder)
 
 Now your theme will be used instead of the default theme.
 
 ## Hiding code lines
 
-There is a feature in mdBook that let's you hide code lines by prepending them with a `#`.
+There is a feature in mdBook that lets you hide code lines by prepending them
+with a `#`.
 
 
 ```bash
@@ -47,13 +52,18 @@ Will render as
 # }
 ```
 
-**At the moment, this only works for code examples that are annotated with `rust`. Because it would collide with semantics of some programming languages. In the future, we want to make this configurable through the `book.toml` so that everyone can benefit from it.**
+**At the moment, this only works for code examples that are annotated with
+`rust`. Because it would collide with semantics of some programming languages.
+In the future, we want to make this configurable through the `book.toml` so that
+everyone can benefit from it.**
 
 
 ## Improve default theme
 
-If you think the default theme doesn't look quite right for a specific language, or could be improved.
-Feel free to [submit a new issue](https://github.com/rust-lang-nursery/mdBook/issues) explaining what you have in mind and I will take a look at it.
+If you think the default theme doesn't look quite right for a specific language,
+or could be improved. Feel free to [submit a new
+issue](https://github.com/rust-lang-nursery/mdBook/issues) explaining what you
+have in mind and I will take a look at it.
 
 You could also create a pull-request with the proposed improvements.
 

book-example/src/misc/contributors.md

@@ -1,8 +1,7 @@
 # Contributors
 
-Here is a list of the contributors who have helped improving mdBook. Big shout-out to them!
-
-If you have contributed to mdBook and I forgot to add you, don't hesitate to add yourself to the list. If you are in the list, feel free to add your real name & contact information if you wish.
+Here is a list of the contributors who have helped improving mdBook. Big
+shout-out to them!
 
 - [mdinger](https://github.com/mdinger)
 - Kevin ([kbknapp](https://github.com/kbknapp))
@@ -12,8 +11,10 @@ If you have contributed to mdBook and I forgot to add you, don't hesitate to add
 - [funnkill](https://github.com/funkill)
 - Fu Gangqiang ([FuGangqiang](https://github.com/FuGangqiang))
 - [Michael-F-Bryan](https://github.com/Michael-F-Bryan)
-- [Chris Spiegel](https://github.com/cspiegel)
+- Chris Spiegel ([cspiegel](https://github.com/cspiegel))
 - [projektir](https://github.com/projektir)
 - [Phaiax](https://github.com/Phaiax)
-- [Matt Ickstadt](https://github.com/mattico)
+- Matt Ickstadt ([mattico](https://github.com/mattico))
 - Weihang Lo ([@weihanglo](https://github.com/weihanglo))
+
+If you feel you're missing from this list, feel free to add yourself in a PR.

build.rs

@@ -1,98 +0,0 @@
-// build.rs
-
-use std::env;
-use std::path::Path;
-#[macro_use]
-extern crate error_chain;
-
-#[cfg(windows)]
-mod execs {
-    use std::process::Command;
-
-    pub fn cmd(program: &str) -> Command {
-        let mut cmd = Command::new("cmd");
-        cmd.args(&["/c", program]);
-        cmd
-    }
-}
-#[cfg(not(windows))]
-mod execs {
-    use std::process::Command;
-
-    pub fn cmd(program: &str) -> Command {
-        Command::new(program)
-    }
-}
-
-
-error_chain!{
- foreign_links {
-        Io(std::io::Error);
-    }
-}
-
-fn program_exists(program: &str) -> Result<()> {
-    execs::cmd(program).arg("-v")
-                       .output()
-                       .chain_err(|| format!("Please install '{}'!", program))?;
-    Ok(())
-}
-
-fn npm_package_exists(package: &str) -> Result<()> {
-    let status = execs::cmd("npm").args(&["list", "-g"])
-                                  .arg(package)
-                                  .output();
-
-    match status {
-        Ok(ref out) if out.status.success() => Ok(()),
-        _ => {
-            bail!("Missing npm package '{0}' install with: 'npm -g install {0}'",
-                  package)
-        }
-    }
-}
-
-pub enum Resource<'a> {
-    Program(&'a str),
-    Package(&'a str),
-}
-use Resource::{Package, Program};
-
-impl<'a> Resource<'a> {
-    pub fn exists(&self) -> Result<()> {
-        match *self {
-            Program(name) => program_exists(name),
-            Package(name) => npm_package_exists(name),
-        }
-    }
-}
-
-fn run() -> Result<()> {
-    if let Ok(_) = env::var("CARGO_FEATURE_REGENERATE_CSS") {
-        // Check dependencies
-        Program("npm").exists()?;
-        Program("node").exists().or(Program("nodejs").exists())?;
-        Package("nib").exists()?;
-        Package("stylus").exists()?;
-
-        // Compile stylus stylesheet to css
-        let manifest_dir = env::var("CARGO_MANIFEST_DIR")
-            .chain_err(|| "Please run the script with: 'cargo build'!")?;
-        let theme_dir = Path::new(&manifest_dir).join("src/theme/");
-        let stylus_dir = theme_dir.join("stylus/book.styl");
-
-        if !execs::cmd("stylus").arg(stylus_dir)
-                                .arg("--out")
-                                .arg(theme_dir)
-                                .arg("--use")
-                                .arg("nib")
-                                .status()?
-                                .success()
-        {
-            bail!("Stylus encountered an error");
-        }
-    }
-    Ok(())
-}
-
-quick_main!(run);

ci/before_deploy.sh

@@ -1,29 +0,0 @@
-# This script takes care of building your crate and packaging it for release
-
-set -ex
-
-main() {
-    local src=$(pwd) \
-          stage=
-
-    case $TRAVIS_OS_NAME in
-        linux)
-            stage=$(mktemp -d)
-            ;;
-        osx)
-            stage=$(mktemp -d -t tmp)
-            ;;
-    esac
-
-    cargo rustc --bin mdbook --target $TARGET --release -- -C lto
-
-    cp target/release/mdbook $stage/
-
-    cd $stage
-    tar czf $src/$CRATE_NAME-$TRAVIS_TAG-$TARGET.tar.gz *
-    cd $src
-
-    rm -rf $stage
-}
-
-main

ci/github_pages.sh

@@ -1,50 +0,0 @@
-#!/bin/bash
-# Deploys the `book-example` to GitHub Pages
-
-set -ex
-
-# Only run this on the master branch for stable
-if [ "$TRAVIS_PULL_REQUEST" != "false" ] || 
-   [ "$TRAVIS_BRANCH" != "master" ] ||
-   [ "$TRAVIS_RUST_VERSION" != "stable" ] ||
-   [ "$TARGET" != "x86_64-unknown-linux-gnu" ]; then
-   exit 0
-fi
-
-# Make sure we have the css dependencies
-npm install -g stylus nib 
-
-NC='\033[39m'
-CYAN='\033[36m'
-GREEN='\033[32m'
-
-rev=$(git rev-parse --short HEAD)
-
-echo -e "${CYAN}Running cargo doc${NC}"
-cargo doc --features regenerate-css > /dev/null
-
-echo -e "${CYAN}Running mdbook build${NC}"
-cargo run -- build book-example/
-
-echo -e "${CYAN}Copying book to target/doc${NC}"
-cp -R book-example/book/* target/doc/
-
-cd target/doc
-
-echo -e "${CYAN}Initializing Git${NC}"
-git init
-git config user.name "Michael Bryan"
-git config user.email "michaelfbryan@gmail.com"
-
-git remote add upstream "https://$GH_TOKEN@github.com/rust-lang-nursery/mdBook.git"
-git fetch upstream --quiet
-git reset upstream/gh-pages --quiet
-
-touch .
-
-echo -e "${CYAN}Pushing changes to gh-pages${NC}"
-git add -A . 
-git commit -m "rebuild pages at ${rev}" --quiet
-git push -q upstream HEAD:gh-pages --quiet
-
-echo -e "${GREEN}Deployed docs to GitHub Pages${NC}"

ci/install-hub.sh

@@ -0,0 +1,24 @@
+#!/usr/bin/env bash
+# Installs the `hub` executable into hub/bin
+set -ex
+case $1 in
+  ubuntu*)
+    curl -LsSf https://github.com/github/hub/releases/download/v2.12.8/hub-linux-amd64-2.12.8.tgz -o hub.tgz
+    mkdir hub
+    tar -xzvf hub.tgz --strip=1 -C hub
+    ;;
+  macos*)
+    curl -LsSf https://github.com/github/hub/releases/download/v2.12.8/hub-darwin-amd64-2.12.8.tgz -o hub.tgz
+    mkdir hub
+    tar -xzvf hub.tgz --strip=1 -C hub
+    ;;
+  windows*)
+    curl -LsSf https://github.com/github/hub/releases/download/v2.12.8/hub-windows-amd64-2.12.8.zip -o hub.zip
+    7z x hub.zip -ohub
+    ;;
+  *)
+    echo "OS should be first parameter, was: $1"
+    ;;
+esac
+
+echo "##[add-path]$PWD/hub/bin"

ci/install-rust.sh

@@ -0,0 +1,19 @@
+#!/usr/bin/env bash
+# Install/update rust.
+# The first argument should be the toolchain to install.
+
+set -ex
+if [ -z "$1" ]
+then
+    echo "First parameter must be toolchain to install."
+    exit 1
+fi
+TOOLCHAIN="$1"
+
+rustup set profile minimal
+rustup component remove --toolchain=$TOOLCHAIN rust-docs || echo "already removed"
+rustup update $TOOLCHAIN
+rustup default $TOOLCHAIN
+rustup -V
+rustc -Vv
+cargo -V

ci/install-rustup.sh

@@ -0,0 +1,26 @@
+#!/usr/bin/env bash
+# Install/update rustup.
+# The first argument should be the toolchain to install.
+#
+# It is helpful to have this as a separate script due to some issues on
+# Windows where immediately after `rustup self update`, rustup can fail with
+# "Device or resource busy".
+
+set -ex
+if [ -z "$1" ]
+then
+    echo "First parameter must be toolchain to install."
+    exit 1
+fi
+TOOLCHAIN="$1"
+
+# Install/update rustup.
+if command -v rustup
+then
+    echo `command -v rustup` `rustup -V` already installed
+    rustup self update
+else
+    # macOS currently does not have rust pre-installed.
+    curl https://sh.rustup.rs -sSf | sh -s -- -y --default-toolchain $TOOLCHAIN --profile=minimal
+    echo "##[add-path]$HOME/.cargo/bin"
+fi

ci/install.sh

@@ -1,47 +0,0 @@
-set -ex
-
-main() {
-    local target=
-    if [ $TRAVIS_OS_NAME = linux ]; then
-        target=x86_64-unknown-linux-musl
-        sort=sort
-    else
-        target=x86_64-apple-darwin
-        sort=gsort  # for `sort --sort-version`, from brew's coreutils.
-    fi
-
-    # Builds for iOS are done on OSX, but require the specific target to be
-    # installed.
-    case $TARGET in
-        aarch64-apple-ios)
-            rustup target install aarch64-apple-ios
-            ;;
-        armv7-apple-ios)
-            rustup target install armv7-apple-ios
-            ;;
-        armv7s-apple-ios)
-            rustup target install armv7s-apple-ios
-            ;;
-        i386-apple-ios)
-            rustup target install i386-apple-ios
-            ;;
-        x86_64-apple-ios)
-            rustup target install x86_64-apple-ios
-            ;;
-    esac
-
-    # This fetches latest stable release
-    local tag=$(git ls-remote --tags --refs --exit-code https://github.com/japaric/cross \
-                       | cut -d/ -f3 \
-                       | grep -E '^v[0.1.0-9.]+$' \
-                       | $sort --version-sort \
-                       | tail -n1)
-    curl -LSfs https://japaric.github.io/trust/install.sh | \
-        sh -s -- \
-           --force \
-           --git japaric/cross \
-           --tag $tag \
-           --target $target
-}
-
-main

ci/make-release.sh

@@ -0,0 +1,36 @@
+#!/usr/bin/env bash
+# Builds the release and creates an archive and optionally deploys to GitHub.
+set -ex
+
+if [[ -z "$GITHUB_REF" ]]
+then
+  echo "GITHUB_REF must be set"
+  exit 1
+fi
+# Strip mdbook-refs/tags/ from the start of the ref.
+TAG=${GITHUB_REF#*/tags/}
+
+host=$(rustc -Vv | grep ^host: | sed -e "s/host: //g")
+cargo rustc --bin mdbook --release -- -C lto
+cd target/release
+case $1 in
+  ubuntu* | macos*)
+    asset="mdbook-$TAG-$host.tar.gz"
+    tar czf ../../$asset mdbook
+    ;;
+  windows*)
+    asset="mdbook-$TAG-$host.zip"
+    7z a ../../$asset mdbook.exe
+    ;;
+  *)
+    echo "OS should be first parameter, was: $1"
+    ;;
+esac
+cd ../..
+
+if [[ -z "$GITHUB_TOKEN" ]]
+then
+  echo "$GITHUB_TOKEN not set, skipping deploy."
+else
+  hub release edit -m "" --attach $asset $TAG
+fi

examples/de-emphasize.rs

@@ -1,94 +0,0 @@
-//! This program removes all forms of emphasis from the markdown of the book.
-extern crate mdbook;
-extern crate pulldown_cmark;
-extern crate pulldown_cmark_to_cmark;
-
-use mdbook::errors::{Error, Result};
-use mdbook::MDBook;
-use mdbook::book::{Book, BookItem, Chapter};
-use mdbook::preprocess::{Preprocessor, PreprocessorContext};
-use pulldown_cmark::{Event, Parser, Tag};
-use pulldown_cmark_to_cmark::fmt::cmark;
-
-use std::ffi::OsString;
-use std::env::{args, args_os};
-use std::process;
-
-struct Deemphasize;
-
-impl Preprocessor for Deemphasize {
-    fn name(&self) -> &str {
-        "md-links-to-html-links"
-    }
-
-    fn run(&self, _ctx: &PreprocessorContext, book: &mut Book) -> Result<()> {
-        eprintln!("Running '{}' preprocessor", self.name());
-        let mut res: Option<_> = None;
-        let mut num_removed_items = 0;
-        book.for_each_mut(|item: &mut BookItem| {
-            if let Some(Err(_)) = res {
-                return;
-            }
-            if let BookItem::Chapter(ref mut chapter) = *item {
-                eprintln!("{}: processing chapter '{}'", self.name(), chapter.name);
-                res = Some(
-                    match Deemphasize::remove_emphasis(&mut num_removed_items, chapter) {
-                        Ok(md) => {
-                            chapter.content = md;
-                            Ok(())
-                        }
-                        Err(err) => Err(err),
-                    },
-                );
-            }
-        });
-        eprintln!(
-            "{}: removed {} events from markdown stream.",
-            self.name(),
-            num_removed_items
-        );
-        match res {
-            Some(res) => res,
-            None => Ok(()),
-        }
-    }
-}
-
-fn do_it(book: OsString) -> Result<()> {
-    let mut book = MDBook::load(book)?;
-    book.with_preprecessor(Deemphasize);
-    book.build()
-}
-
-fn main() {
-    if args_os().count() != 2 {
-        eprintln!("USAGE: {} <book>", args().next().expect("executable"));
-        return;
-    }
-    if let Err(e) = do_it(args_os().skip(1).next().expect("one argument")) {
-        eprintln!("{}", e);
-        process::exit(1);
-    }
-}
-
-impl Deemphasize {
-    fn remove_emphasis(num_removed_items: &mut i32, chapter: &mut Chapter) -> Result<String> {
-        let mut buf = String::with_capacity(chapter.content.len());
-        let events = Parser::new(&chapter.content).filter(|e| {
-            let should_keep = match *e {
-                Event::Start(Tag::Emphasis)
-                | Event::Start(Tag::Strong)
-                | Event::End(Tag::Emphasis)
-                | Event::End(Tag::Strong) => false,
-                _ => true,
-            };
-            if !should_keep {
-                *num_removed_items += 1;
-            }
-            should_keep
-        });
-        cmark(events, &mut buf, None)
-            .map(|_| buf)
-            .map_err(|err| Error::from(format!("Markdown serialization failed: {}", err)))
-    }
-}

examples/nop-preprocessor.rs

@@ -0,0 +1,102 @@
+use crate::nop_lib::Nop;
+use clap::{App, Arg, ArgMatches, SubCommand};
+use mdbook::book::Book;
+use mdbook::errors::Error;
+use mdbook::preprocess::{CmdPreprocessor, Preprocessor, PreprocessorContext};
+use std::io;
+use std::process;
+
+pub fn make_app() -> App<'static, 'static> {
+    App::new("nop-preprocessor")
+        .about("A mdbook preprocessor which does precisely nothing")
+        .subcommand(
+            SubCommand::with_name("supports")
+                .arg(Arg::with_name("renderer").required(true))
+                .about("Check whether a renderer is supported by this preprocessor"),
+        )
+}
+
+fn main() {
+    let matches = make_app().get_matches();
+
+    // Users will want to construct their own preprocessor here
+    let preprocessor = Nop::new();
+
+    if let Some(sub_args) = matches.subcommand_matches("supports") {
+        handle_supports(&preprocessor, sub_args);
+    } else if let Err(e) = handle_preprocessing(&preprocessor) {
+        eprintln!("{}", e);
+        process::exit(1);
+    }
+}
+
+fn handle_preprocessing(pre: &dyn Preprocessor) -> Result<(), Error> {
+    let (ctx, book) = CmdPreprocessor::parse_input(io::stdin())?;
+
+    if ctx.mdbook_version != mdbook::MDBOOK_VERSION {
+        // We should probably use the `semver` crate to check compatibility
+        // here...
+        eprintln!(
+            "Warning: The {} plugin was built against version {} of mdbook, \
+             but we're being called from version {}",
+            pre.name(),
+            mdbook::MDBOOK_VERSION,
+            ctx.mdbook_version
+        );
+    }
+
+    let processed_book = pre.run(&ctx, book)?;
+    serde_json::to_writer(io::stdout(), &processed_book)?;
+
+    Ok(())
+}
+
+fn handle_supports(pre: &dyn Preprocessor, sub_args: &ArgMatches) -> ! {
+    let renderer = sub_args.value_of("renderer").expect("Required argument");
+    let supported = pre.supports_renderer(&renderer);
+
+    // Signal whether the renderer is supported by exiting with 1 or 0.
+    if supported {
+        process::exit(0);
+    } else {
+        process::exit(1);
+    }
+}
+
+/// The actual implementation of the `Nop` preprocessor. This would usually go
+/// in your main `lib.rs` file.
+mod nop_lib {
+    use super::*;
+
+    /// A no-op preprocessor.
+    pub struct Nop;
+
+    impl Nop {
+        pub fn new() -> Nop {
+            Nop
+        }
+    }
+
+    impl Preprocessor for Nop {
+        fn name(&self) -> &str {
+            "nop-preprocessor"
+        }
+
+        fn run(&self, ctx: &PreprocessorContext, book: Book) -> Result<Book, Error> {
+            // In testing we want to tell the preprocessor to blow up by setting a
+            // particular config value
+            if let Some(nop_cfg) = ctx.config.get_preprocessor(self.name()) {
+                if nop_cfg.contains_key("blow-up") {
+                    return Err("Boom!!1!".into());
+                }
+            }
+
+            // we *are* a no-op preprocessor after all
+            Ok(book)
+        }
+
+        fn supports_renderer(&self, renderer: &str) -> bool {
+            renderer != "not-supported"
+        }
+    }
+}

rustfmt.toml

@@ -1 +0,0 @@
-format_strings = true

src/bin/clean.rs

@@ -1,30 +0,0 @@
-use std::fs;
-use std::path::PathBuf;
-use clap::{App, ArgMatches, SubCommand};
-use mdbook::MDBook;
-use mdbook::errors::*;
-use get_book_dir;
-
-// Create clap subcommand arguments
-pub fn make_subcommand<'a, 'b>() -> App<'a, 'b> {
-    SubCommand::with_name("clean")
-        .about("Delete built book")
-        .arg_from_usage(
-            "-d, --dest-dir=[dest-dir] 'The directory of built book{n}(Defaults to ./book when \
-             omitted)'",
-        )
-}
-
-// Clean command implementation
-pub fn execute(args: &ArgMatches) -> ::mdbook::errors::Result<()> {
-    let book_dir = get_book_dir(args);
-    let book = MDBook::load(&book_dir)?;
-
-    let dir_to_remove = match args.value_of("dest-dir") {
-        Some(dest_dir) => PathBuf::from(dest_dir),
-        None => book.root.join(&book.config.build.build_dir),
-    };
-    fs::remove_dir_all(&dir_to_remove).chain_err(|| "Unable to remove the build directory")?;
-
-    Ok(())
-}

src/bin/serve.rs

@@ -1,117 +0,0 @@
-extern crate iron;
-extern crate staticfile;
-extern crate ws;
-
-use std;
-use self::iron::{status, AfterMiddleware, Chain, Iron, IronError, IronResult, Request, Response,
-                 Set};
-use clap::{App, ArgMatches, SubCommand};
-use mdbook::MDBook;
-use mdbook::utils;
-use mdbook::errors::*;
-use {get_book_dir, open};
-#[cfg(feature = "watch")]
-use watch;
-
-struct ErrorRecover;
-
-// Create clap subcommand arguments
-pub fn make_subcommand<'a, 'b>() -> App<'a, 'b> {
-    SubCommand::with_name("serve")
-        .about("Serve the book at http://localhost:3000. Rebuild and reload on change.")
-        .arg_from_usage(
-            "[dir] 'A directory for your book{n}(Defaults to Current Directory when omitted)'",
-        )
-        .arg_from_usage("-p, --port=[port] 'Use another port{n}(Defaults to 3000)'")
-        .arg_from_usage(
-            "-w, --websocket-port=[ws-port] 'Use another port for the websocket connection \
-             (livereload){n}(Defaults to 3001)'",
-        )
-        .arg_from_usage(
-            "-i, --interface=[interface] 'Interface to listen on{n}(Defaults to localhost)'",
-        )
-        .arg_from_usage(
-            "-a, --address=[address] 'Address that the browser can reach the websocket server \
-             from{n}(Defaults to the interface address)'",
-        )
-        .arg_from_usage("-o, --open 'Open the book server in a web browser'")
-}
-
-// Watch command implementation
-pub fn execute(args: &ArgMatches) -> Result<()> {
-    let book_dir = get_book_dir(args);
-    let mut book = MDBook::load(&book_dir)?;
-
-    let port = args.value_of("port").unwrap_or("3000");
-    let ws_port = args.value_of("websocket-port").unwrap_or("3001");
-    let interface = args.value_of("interface").unwrap_or("localhost");
-    let public_address = args.value_of("address").unwrap_or(interface);
-    let open_browser = args.is_present("open");
-
-    let address = format!("{}:{}", interface, port);
-    let ws_address = format!("{}:{}", interface, ws_port);
-
-    let livereload_url = format!("ws://{}:{}", public_address, ws_port);
-    book.config
-        .set("output.html.livereload-url", &livereload_url)?;
-
-    book.build()?;
-
-    let mut chain = Chain::new(staticfile::Static::new(book.build_dir_for("html")));
-    chain.link_after(ErrorRecover);
-    let _iron = Iron::new(chain)
-        .http(&*address)
-        .chain_err(|| "Unable to launch the server")?;
-
-    let ws_server =
-        ws::WebSocket::new(|_| |_| Ok(())).chain_err(|| "Unable to start the websocket")?;
-
-    let broadcaster = ws_server.broadcaster();
-
-    std::thread::spawn(move || {
-        ws_server.listen(&*ws_address).unwrap();
-    });
-
-    let serving_url = format!("http://{}", address);
-    info!("Serving on: {}", serving_url);
-
-    if open_browser {
-        open(serving_url);
-    }
-
-    #[cfg(feature = "watch")]
-    watch::trigger_on_change(&mut book, move |path, book_dir| {
-        info!("File changed: {:?}", path);
-        info!("Building book...");
-
-        // FIXME: This area is really ugly because we need to re-set livereload :(
-
-        let livereload_url = livereload_url.clone();
-
-        let result = MDBook::load(&book_dir)
-            .and_then(move |mut b| {
-                b.config.set("output.html.livereload-url", &livereload_url)?;
-                Ok(b)
-            })
-            .and_then(|b| b.build());
-
-        if let Err(e) = result {
-            error!("Unable to load the book");
-            utils::log_backtrace(&e);
-        } else {
-            let _ = broadcaster.send("reload");
-        }
-    });
-
-    Ok(())
-}
-
-impl AfterMiddleware for ErrorRecover {
-    fn catch(&self, _: &mut Request, err: IronError) -> IronResult<Response> {
-        match err.response.status {
-            // each error will result in 404 response
-            Some(_) => Ok(err.response.set(status::NotFound)),
-            _ => Err(err),
-        }
-    }
-}

src/bin/test.rs

@@ -1,26 +0,0 @@
-use clap::{App, ArgMatches, SubCommand};
-use mdbook::MDBook;
-use mdbook::errors::Result;
-use get_book_dir;
-
-// Create clap subcommand arguments
-pub fn make_subcommand<'a, 'b>() -> App<'a, 'b> {
-    SubCommand::with_name("test")
-        .about("Test that code samples compile")
-        .arg_from_usage(
-            "-L, --library-path [DIR]... 'directory to add to crate search path'",
-        )
-}
-
-// test command implementation
-pub fn execute(args: &ArgMatches) -> Result<()> {
-    let library_paths: Vec<&str> = args.values_of("library-path")
-                                       .map(|v| v.collect())
-                                       .unwrap_or_default();
-    let book_dir = get_book_dir(args);
-    let mut book = MDBook::load(&book_dir)?;
-
-    book.test(library_paths)?;
-
-    Ok(())
-}

src/bin/watch.rs

@@ -1,87 +0,0 @@
-extern crate notify;
-
-use std::path::Path;
-use self::notify::Watcher;
-use std::time::Duration;
-use std::sync::mpsc::channel;
-use clap::{App, ArgMatches, SubCommand};
-use mdbook::MDBook;
-use mdbook::utils;
-use mdbook::errors::Result;
-use {get_book_dir, open};
-
-// Create clap subcommand arguments
-pub fn make_subcommand<'a, 'b>() -> App<'a, 'b> {
-    SubCommand::with_name("watch")
-        .about("Watch the files for changes")
-        .arg_from_usage("-o, --open 'Open the compiled book in a web browser'")
-        .arg_from_usage(
-            "[dir] 'A directory for your book{n}(Defaults to Current Directory when omitted)'",
-        )
-}
-
-// Watch command implementation
-pub fn execute(args: &ArgMatches) -> Result<()> {
-    let book_dir = get_book_dir(args);
-    let book = MDBook::load(&book_dir)?;
-
-    if args.is_present("open") {
-        book.build()?;
-        open(book.build_dir_for("html").join("index.html"));
-    }
-
-    trigger_on_change(&book, |path, book_dir| {
-        info!("File changed: {:?}\nBuilding book...\n", path);
-        let result = MDBook::load(&book_dir).and_then(|b| b.build());
-
-        if let Err(e) = result {
-            error!("Unable to build the book");
-            utils::log_backtrace(&e);
-        }
-    });
-
-    Ok(())
-}
-
-/// Calls the closure when a book source file is changed, blocking indefinitely.
-pub fn trigger_on_change<F>(book: &MDBook, closure: F)
-where
-    F: Fn(&Path, &Path),
-{
-    use self::notify::RecursiveMode::*;
-    use self::notify::DebouncedEvent::*;
-
-    // Create a channel to receive the events.
-    let (tx, rx) = channel();
-
-    let mut watcher = match notify::watcher(tx, Duration::from_secs(1)) {
-        Ok(w) => w,
-        Err(e) => {
-            error!("Error while trying to watch the files:\n\n\t{:?}", e);
-            ::std::process::exit(1)
-        }
-    };
-
-    // Add the source directory to the watcher
-    if let Err(e) = watcher.watch(book.source_dir(), Recursive) {
-        error!("Error while watching {:?}:\n    {:?}", book.source_dir(), e);
-        ::std::process::exit(1);
-    };
-
-    let _ = watcher.watch(book.theme_dir(), Recursive);
-
-    // Add the book.toml file to the watcher if it exists
-    let _ = watcher.watch(book.root.join("book.toml"), NonRecursive);
-
-    info!("Listening for changes...");
-
-    for event in rx.iter() {
-        debug!("Received filesystem event: {:?}", event);
-        match event {
-            Create(path) | Write(path) | Remove(path) | Rename(_, path) => {
-                closure(&path, &book.root);
-            }
-            _ => {}
-        }
-    }
-}

src/book/book.rs

@@ -1,12 +1,12 @@
-use std::fmt::{self, Display, Formatter};
-use std::path::{Path, PathBuf};
 use std::collections::VecDeque;
+use std::fmt::{self, Display, Formatter};
 use std::fs::{self, File};
 use std::io::{Read, Write};
+use std::path::{Path, PathBuf};
 
 use super::summary::{parse_summary, Link, SectionNumber, Summary, SummaryItem};
-use config::BuildConfig;
-use errors::*;
+use crate::config::BuildConfig;
+use crate::errors::*;
 
 /// Load a book into memory from its `src/` directory.
 pub fn load_book<P: AsRef<Path>>(src_dir: P, cfg: &BuildConfig) -> Result<Book> {
@@ -82,7 +82,7 @@ impl Book {
     }
 
     /// Get a depth-first iterator over the items in the book.
-    pub fn iter(&self) -> BookItems {
+    pub fn iter(&self) -> BookItems<'_> {
         BookItems {
             items: self.sections.iter().collect(),
         }
@@ -116,7 +116,7 @@ where
     I: IntoIterator<Item = &'a mut BookItem>,
 {
     for item in items {
-        if let &mut BookItem::Chapter(ref mut ch) = item {
+        if let BookItem::Chapter(ch) = item {
             for_each_mut(func, &mut ch.sub_items);
         }
 
@@ -167,9 +167,9 @@ impl Chapter {
     ) -> Chapter {
         Chapter {
             name: name.to_string(),
-            content: content,
+            content,
             path: path.into(),
-            parent_names: parent_names,
+            parent_names,
             ..Default::default()
         }
     }
@@ -179,7 +179,7 @@ impl Chapter {
 ///
 /// You need to pass in the book's source directory because all the links in
 /// `SUMMARY.md` give the chapter locations relative to it.
-fn load_book_from_disk<P: AsRef<Path>>(summary: &Summary, src_dir: P) -> Result<Book> {
+pub(crate) fn load_book_from_disk<P: AsRef<Path>>(summary: &Summary, src_dir: P) -> Result<Book> {
     debug!("Loading the book from disk");
     let src_dir = src_dir.as_ref();
 
@@ -210,7 +210,7 @@ fn load_summary_item<P: AsRef<Path>>(
     match *item {
         SummaryItem::Separator => Ok(BookItem::Separator),
         SummaryItem::Link(ref link) => {
-            load_chapter(link, src_dir, parent_names).map(|c| BookItem::Chapter(c))
+            load_chapter(link, src_dir, parent_names).map(BookItem::Chapter)
         }
     }
 }
@@ -245,7 +245,8 @@ fn load_chapter<P: AsRef<Path>>(
     ch.number = link.number.clone();
 
     sub_item_parents.push(link.name.clone());
-    let sub_items = link.nested_items
+    let sub_items = link
+        .nested_items
         .iter()
         .map(|i| load_summary_item(i, src_dir, sub_item_parents.clone()))
         .collect::<Result<Vec<_>>>()?;
@@ -285,7 +286,7 @@ impl<'a> Iterator for BookItems<'a> {
 }
 
 impl Display for Chapter {
-    fn fmt(&self, f: &mut Formatter) -> fmt::Result {
+    fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
         if let Some(ref section_number) = self.number {
             write!(f, "{} ", section_number)?;
         }
@@ -297,10 +298,10 @@ impl Display for Chapter {
 #[cfg(test)]
 mod tests {
     use super::*;
-    use tempfile::{TempDir, Builder as TempFileBuilder};
     use std::io::Write;
+    use tempfile::{Builder as TempFileBuilder, TempDir};
 
-    const DUMMY_SRC: &'static str = "
+    const DUMMY_SRC: &str = "
 # Dummy Chapter
 
 this is some dummy text.
@@ -316,7 +317,7 @@ And here is some \
         let chapter_path = temp.path().join("chapter_1.md");
         File::create(&chapter_path)
             .unwrap()
-            .write(DUMMY_SRC.as_bytes())
+            .write_all(DUMMY_SRC.as_bytes())
             .unwrap();
 
         let link = Link::new("Chapter 1", chapter_path);
@@ -332,7 +333,7 @@ And here is some \
 
         File::create(&second_path)
             .unwrap()
-            .write_all("Hello World!".as_bytes())
+            .write_all(b"Hello World!")
             .unwrap();
 
         let mut second = Link::new("Nested Chapter 1", &second_path);
@@ -404,14 +405,12 @@ And here is some \
             ..Default::default()
         };
         let should_be = Book {
-            sections: vec![
-                BookItem::Chapter(Chapter {
-                    name: String::from("Chapter 1"),
-                    content: String::from(DUMMY_SRC),
-                    path: PathBuf::from("chapter_1.md"),
-                    ..Default::default()
-                }),
-            ],
+            sections: vec![BookItem::Chapter(Chapter {
+                name: String::from("Chapter 1"),
+                content: String::from(DUMMY_SRC),
+                path: PathBuf::from("chapter_1.md"),
+                ..Default::default()
+            })],
             ..Default::default()
         };
 
@@ -477,7 +476,8 @@ And here is some \
         assert_eq!(got.len(), 5);
 
         // checking the chapter names are in the order should be sufficient here...
-        let chapter_names: Vec<String> = got.into_iter()
+        let chapter_names: Vec<String> = got
+            .into_iter()
             .filter_map(|i| match *i {
                 BookItem::Chapter(ref ch) => Some(ch.name.clone()),
                 _ => None,
@@ -535,13 +535,11 @@ And here is some \
     fn cant_load_chapters_with_an_empty_path() {
         let (_, temp) = dummy_link();
         let summary = Summary {
-            numbered_chapters: vec![
-                SummaryItem::Link(Link {
-                    name: String::from("Empty"),
-                    location: PathBuf::from(""),
-                    ..Default::default()
-                }),
-            ],
+            numbered_chapters: vec![SummaryItem::Link(Link {
+                name: String::from("Empty"),
+                location: PathBuf::from(""),
+                ..Default::default()
+            })],
             ..Default::default()
         };
 
@@ -556,13 +554,11 @@ And here is some \
         fs::create_dir(&dir).unwrap();
 
         let summary = Summary {
-            numbered_chapters: vec![
-                SummaryItem::Link(Link {
-                    name: String::from("nested"),
-                    location: dir,
-                    ..Default::default()
-                }),
-            ],
+            numbered_chapters: vec![SummaryItem::Link(Link {
+                name: String::from("nested"),
+                location: dir,
+                ..Default::default()
+            })],
             ..Default::default()
         };
 

src/book/init.rs

@@ -1,12 +1,11 @@
 use std::fs::{self, File};
-use std::path::PathBuf;
 use std::io::Write;
-use toml;
+use std::path::PathBuf;
 
-use config::Config;
 use super::MDBook;
-use theme;
-use errors::*;
+use crate::config::Config;
+use crate::errors::*;
+use crate::theme;
 
 /// A helper for setting up a new book and its directory structure.
 #[derive(Debug, Clone, PartialEq)]
@@ -110,7 +109,8 @@ impl BookBuilder {
     fn copy_across_theme(&self) -> Result<()> {
         debug!("Copying theme");
 
-        let themedir = self.config
+        let themedir = self
+            .config
             .html_config()
             .and_then(|html| html.theme)
             .unwrap_or_else(|| self.config.book.src.join("theme"));
@@ -127,8 +127,20 @@ impl BookBuilder {
         let mut index = File::create(themedir.join("index.hbs"))?;
         index.write_all(theme::INDEX)?;
 
-        let mut css = File::create(themedir.join("book.css"))?;
-        css.write_all(theme::CSS)?;
+        let cssdir = themedir.join("css");
+        fs::create_dir(&cssdir)?;
+
+        let mut general_css = File::create(cssdir.join("general.css"))?;
+        general_css.write_all(theme::GENERAL_CSS)?;
+
+        let mut chrome_css = File::create(cssdir.join("chrome.css"))?;
+        chrome_css.write_all(theme::CHROME_CSS)?;
+
+        let mut print_css = File::create(cssdir.join("print.css"))?;
+        print_css.write_all(theme::PRINT_CSS)?;
+
+        let mut variables_css = File::create(cssdir.join("variables.css"))?;
+        variables_css.write_all(theme::VARIABLES_CSS)?;
 
         let mut favicon = File::create(themedir.join("favicon.png"))?;
         favicon.write_all(theme::FAVICON)?;
@@ -160,15 +172,19 @@ impl BookBuilder {
         let src_dir = self.root.join(&self.config.book.src);
 
         let summary = src_dir.join("SUMMARY.md");
-        let mut f = File::create(&summary).chain_err(|| "Unable to create SUMMARY.md")?;
-        writeln!(f, "# Summary")?;
-        writeln!(f, "")?;
-        writeln!(f, "- [Chapter 1](./chapter_1.md)")?;
-
-        let chapter_1 = src_dir.join("chapter_1.md");
-        let mut f = File::create(&chapter_1).chain_err(|| "Unable to create chapter_1.md")?;
-        writeln!(f, "# Chapter 1")?;
+        if !summary.exists() {
+            trace!("No summary found creating stub summary and chapter_1.md.");
+            let mut f = File::create(&summary).chain_err(|| "Unable to create SUMMARY.md")?;
+            writeln!(f, "# Summary")?;
+            writeln!(f)?;
+            writeln!(f, "- [Chapter 1](./chapter_1.md)")?;
 
+            let chapter_1 = src_dir.join("chapter_1.md");
+            let mut f = File::create(&chapter_1).chain_err(|| "Unable to create chapter_1.md")?;
+            writeln!(f, "# Chapter 1")?;
+        } else {
+            trace!("Existing summary found, no need to create stub files.");
+        }
         Ok(())
     }
 

src/book/mod.rs

@@ -5,31 +5,29 @@
 //!
 //! [1]: ../index.html
 
-mod summary;
 mod book;
 mod init;
+mod summary;
 
 pub use self::book::{load_book, Book, BookItem, BookItems, Chapter};
-pub use self::summary::{parse_summary, Link, SectionNumber, Summary, SummaryItem};
 pub use self::init::BookBuilder;
+pub use self::summary::{parse_summary, Link, SectionNumber, Summary, SummaryItem};
 
-use std::path::PathBuf;
 use std::io::Write;
+use std::path::PathBuf;
 use std::process::Command;
+use std::string::ToString;
 use tempfile::Builder as TempFileBuilder;
 use toml::Value;
 
-use utils;
-use renderer::{CmdRenderer, HtmlHandlebars, RenderContext, Renderer};
-use preprocess::{
-    LinkPreprocessor,
-    IndexPreprocessor,
-    Preprocessor,
-    PreprocessorContext
+use crate::errors::*;
+use crate::preprocess::{
+    CmdPreprocessor, IndexPreprocessor, LinkPreprocessor, Preprocessor, PreprocessorContext,
 };
-use errors::*;
+use crate::renderer::{CmdRenderer, HtmlHandlebars, MarkdownRenderer, RenderContext, Renderer};
+use crate::utils;
 
-use config::Config;
+use crate::config::Config;
 
 /// The object used to manage and build a book.
 pub struct MDBook {
@@ -39,10 +37,10 @@ pub struct MDBook {
     pub config: Config,
     /// A representation of the book's contents in memory.
     pub book: Book,
-    renderers: Vec<Box<Renderer>>,
+    renderers: Vec<Box<dyn Renderer>>,
 
     /// List of pre-processors to be run on the book
-    preprocessors: Vec<Box<Preprocessor>>,
+    preprocessors: Vec<Box<dyn Preprocessor>>,
 }
 
 impl MDBook {
@@ -70,7 +68,7 @@ impl MDBook {
 
         config.update_from_env();
 
-        if log_enabled!(::log::Level::Trace) {
+        if log_enabled!(log::Level::Trace) {
             for line in format!("Config: {:#?}", config).lines() {
                 trace!("{}", line);
             }
@@ -98,12 +96,34 @@ impl MDBook {
         })
     }
 
+    /// Load a book from its root directory using a custom config and a custom summary.
+    pub fn load_with_config_and_summary<P: Into<PathBuf>>(
+        book_root: P,
+        config: Config,
+        summary: Summary,
+    ) -> Result<MDBook> {
+        let root = book_root.into();
+
+        let src_dir = root.join(&config.book.src);
+        let book = book::load_book_from_disk(&summary, &src_dir)?;
+
+        let renderers = determine_renderers(&config);
+        let preprocessors = determine_preprocessors(&config)?;
+
+        Ok(MDBook {
+            root,
+            config,
+            book,
+            renderers,
+            preprocessors,
+        })
+    }
+
     /// Returns a flat depth-first iterator over the elements of the book,
     /// it returns an [BookItem enum](bookitem.html):
     /// `(section: String, bookitem: &BookItem)`
     ///
     /// ```no_run
-    /// # extern crate mdbook;
     /// # use mdbook::MDBook;
     /// # use mdbook::book::BookItem;
     /// # #[allow(unused_variables)]
@@ -125,7 +145,7 @@ impl MDBook {
     /// // etc.
     /// # }
     /// ```
-    pub fn iter(&self) -> BookItems {
+    pub fn iter(&self) -> BookItems<'_> {
         self.book.iter()
     }
 
@@ -154,35 +174,38 @@ impl MDBook {
     pub fn build(&self) -> Result<()> {
         info!("Book building has started");
 
-        let mut preprocessed_book = self.book.clone();
-        let preprocess_ctx = PreprocessorContext::new(self.root.clone(), self.config.clone());
-
-        for preprocessor in &self.preprocessors {
-            debug!("Running the {} preprocessor.", preprocessor.name());
-            preprocessor.run(&preprocess_ctx, &mut preprocessed_book)?;
-        }
-
         for renderer in &self.renderers {
-            info!("Running the {} backend", renderer.name());
-            self.run_renderer(&preprocessed_book, renderer.as_ref())?;
+            self.execute_build_process(&**renderer)?;
         }
 
         Ok(())
     }
 
-    fn run_renderer(&self, preprocessed_book: &Book, renderer: &Renderer) -> Result<()> {
+    /// Run the entire build process for a particular `Renderer`.
+    fn execute_build_process(&self, renderer: &dyn Renderer) -> Result<()> {
+        let mut preprocessed_book = self.book.clone();
+        let preprocess_ctx = PreprocessorContext::new(
+            self.root.clone(),
+            self.config.clone(),
+            renderer.name().to_string(),
+        );
+
+        for preprocessor in &self.preprocessors {
+            if preprocessor_should_run(&**preprocessor, renderer, &self.config) {
+                debug!("Running the {} preprocessor.", preprocessor.name());
+                preprocessed_book = preprocessor.run(&preprocess_ctx, preprocessed_book)?;
+            }
+        }
+
+        info!("Running the {} backend", renderer.name());
+        self.render(&preprocessed_book, renderer)?;
+
+        Ok(())
+    }
+
+    fn render(&self, preprocessed_book: &Book, renderer: &dyn Renderer) -> Result<()> {
         let name = renderer.name();
         let build_dir = self.build_dir_for(name);
-        if build_dir.exists() {
-            debug!(
-                "Cleaning build dir for the \"{}\" renderer ({})",
-                name,
-                build_dir.display()
-            );
-
-            utils::fs::remove_dir_content(&build_dir)
-                .chain_err(|| "Unable to clear output directory")?;
-        }
 
         let render_context = RenderContext::new(
             self.root.clone(),
@@ -205,7 +228,7 @@ impl MDBook {
     }
 
     /// Register a [`Preprocessor`](../preprocess/trait.Preprocessor.html) to be used when rendering the book.
-    pub fn with_preprecessor<P: Preprocessor + 'static>(&mut self, preprocessor: P) -> &mut Self {
+    pub fn with_preprocessor<P: Preprocessor + 'static>(&mut self, preprocessor: P) -> &mut Self {
         self.preprocessors.push(Box::new(preprocessor));
         self
     }
@@ -218,24 +241,26 @@ impl MDBook {
             .flat_map(|x| vec![x.0, x.1])
             .collect();
 
-        let temp_dir = TempFileBuilder::new().prefix("mdbook").tempdir()?;
+        let temp_dir = TempFileBuilder::new().prefix("mdbook-").tempdir()?;
 
-        let preprocess_context = PreprocessorContext::new(self.root.clone(), self.config.clone());
+        // FIXME: Is "test" the proper renderer name to use here?
+        let preprocess_context =
+            PreprocessorContext::new(self.root.clone(), self.config.clone(), "test".to_string());
 
-        LinkPreprocessor::new().run(&preprocess_context, &mut self.book)?;
-        IndexPreprocessor::new().run(&preprocess_context, &mut self.book)?;
+        let book = LinkPreprocessor::new().run(&preprocess_context, self.book.clone())?;
+        // Index Preprocessor is disabled so that chapter paths continue to point to the
+        // actual markdown files.
 
-        for item in self.iter() {
+        for item in book.iter() {
             if let BookItem::Chapter(ref ch) = *item {
                 if !ch.path.as_os_str().is_empty() {
                     let path = self.source_dir().join(&ch.path);
-                    let content = utils::fs::file_to_string(&path)?;
                     info!("Testing file: {:?}", path);
 
                     // write preprocessed file to tempdir
                     let path = temp_dir.path().join(&ch.path);
                     let mut tmpf = utils::fs::create_file(&path)?;
-                    tmpf.write_all(content.as_bytes())?;
+                    tmpf.write_all(ch.content.as_bytes())?;
 
                     let output = Command::new("rustdoc")
                         .arg(&path)
@@ -304,19 +329,19 @@ impl MDBook {
 }
 
 /// Look at the `Config` and try to figure out what renderers to use.
-fn determine_renderers(config: &Config) -> Vec<Box<Renderer>> {
-    let mut renderers: Vec<Box<Renderer>> = Vec::new();
+fn determine_renderers(config: &Config) -> Vec<Box<dyn Renderer>> {
+    let mut renderers = Vec::new();
 
-    if let Some(output_table) = config.get("output").and_then(|o| o.as_table()) {
-        for (key, table) in output_table.iter() {
-            // the "html" backend has its own Renderer
+    if let Some(output_table) = config.get("output").and_then(Value::as_table) {
+        renderers.extend(output_table.iter().map(|(key, table)| {
             if key == "html" {
-                renderers.push(Box::new(HtmlHandlebars::new()));
+                Box::new(HtmlHandlebars::new()) as Box<dyn Renderer>
+            } else if key == "markdown" {
+                Box::new(MarkdownRenderer::new()) as Box<dyn Renderer>
             } else {
-                let renderer = interpret_custom_renderer(key, table);
-                renderers.push(renderer);
+                interpret_custom_renderer(key, table)
             }
-        }
+        }));
     }
 
     // if we couldn't find anything, add the HTML renderer as a default
@@ -327,52 +352,98 @@ fn determine_renderers(config: &Config) -> Vec<Box<Renderer>> {
     renderers
 }
 
-fn default_preprocessors() -> Vec<Box<Preprocessor>> {
+fn default_preprocessors() -> Vec<Box<dyn Preprocessor>> {
     vec![
         Box::new(LinkPreprocessor::new()),
         Box::new(IndexPreprocessor::new()),
     ]
 }
 
+fn is_default_preprocessor(pre: &dyn Preprocessor) -> bool {
+    let name = pre.name();
+    name == LinkPreprocessor::NAME || name == IndexPreprocessor::NAME
+}
+
 /// Look at the `MDBook` and try to figure out what preprocessors to run.
-fn determine_preprocessors(config: &Config) -> Result<Vec<Box<Preprocessor>>> {
-    let preprocess_list = match config.build.preprocess {
-        Some(ref p) => p,
-        // If no preprocessor field is set, default to the LinkPreprocessor and
-        // IndexPreprocessor. This allows you to disable default preprocessors
-        // by setting "preprocess" to an empty list.
-        None => return Ok(default_preprocessors()),
-    };
+fn determine_preprocessors(config: &Config) -> Result<Vec<Box<dyn Preprocessor>>> {
+    let mut preprocessors = Vec::new();
 
-    let mut preprocessors: Vec<Box<Preprocessor>> = Vec::new();
+    if config.build.use_default_preprocessors {
+        preprocessors.extend(default_preprocessors());
+    }
 
-    for key in preprocess_list {
-        match key.as_ref() {
-            "links" => preprocessors.push(Box::new(LinkPreprocessor::new())),
-            "index" => preprocessors.push(Box::new(IndexPreprocessor::new())),
-            _ => bail!("{:?} is not a recognised preprocessor", key),
+    if let Some(preprocessor_table) = config.get("preprocessor").and_then(Value::as_table) {
+        for key in preprocessor_table.keys() {
+            match key.as_ref() {
+                "links" => preprocessors.push(Box::new(LinkPreprocessor::new())),
+                "index" => preprocessors.push(Box::new(IndexPreprocessor::new())),
+                name => preprocessors.push(interpret_custom_preprocessor(
+                    name,
+                    &preprocessor_table[name],
+                )),
+            }
         }
     }
 
     Ok(preprocessors)
 }
 
-fn interpret_custom_renderer(key: &str, table: &Value) -> Box<Renderer> {
+fn interpret_custom_preprocessor(key: &str, table: &Value) -> Box<CmdPreprocessor> {
+    let command = table
+        .get("command")
+        .and_then(Value::as_str)
+        .map(ToString::to_string)
+        .unwrap_or_else(|| format!("mdbook-{}", key));
+
+    Box::new(CmdPreprocessor::new(key.to_string(), command.to_string()))
+}
+
+fn interpret_custom_renderer(key: &str, table: &Value) -> Box<CmdRenderer> {
     // look for the `command` field, falling back to using the key
     // prepended by "mdbook-"
     let table_dot_command = table
         .get("command")
-        .and_then(|c| c.as_str())
-        .map(|s| s.to_string());
+        .and_then(Value::as_str)
+        .map(ToString::to_string);
 
     let command = table_dot_command.unwrap_or_else(|| format!("mdbook-{}", key));
 
     Box::new(CmdRenderer::new(key.to_string(), command.to_string()))
 }
 
+/// Check whether we should run a particular `Preprocessor` in combination
+/// with the renderer, falling back to `Preprocessor::supports_renderer()`
+/// method if the user doesn't say anything.
+///
+/// The `build.use-default-preprocessors` config option can be used to ensure
+/// default preprocessors always run if they support the renderer.
+fn preprocessor_should_run(
+    preprocessor: &dyn Preprocessor,
+    renderer: &dyn Renderer,
+    cfg: &Config,
+) -> bool {
+    // default preprocessors should be run by default (if supported)
+    if cfg.build.use_default_preprocessors && is_default_preprocessor(preprocessor) {
+        return preprocessor.supports_renderer(renderer.name());
+    }
+
+    let key = format!("preprocessor.{}.renderers", preprocessor.name());
+    let renderer_name = renderer.name();
+
+    if let Some(Value::Array(ref explicit_renderers)) = cfg.get(&key) {
+        return explicit_renderers
+            .iter()
+            .filter_map(Value::as_str)
+            .any(|name| name == renderer_name);
+    }
+
+    preprocessor.supports_renderer(renderer_name)
+}
+
 #[cfg(test)]
 mod tests {
     use super::*;
+    use std::str::FromStr;
     use toml::value::{Table, Value};
 
     #[test]
@@ -417,8 +488,8 @@ mod tests {
     fn config_defaults_to_link_and_index_preprocessor_if_not_set() {
         let cfg = Config::default();
 
-        // make sure we haven't got anything in the `output` table
-        assert!(cfg.build.preprocess.is_none());
+        // make sure we haven't got anything in the `preprocessor` table
+        assert!(cfg.get("preprocessor").is_none());
 
         let got = determine_preprocessors(&cfg);
 
@@ -429,47 +500,105 @@ mod tests {
     }
 
     #[test]
-    fn config_doesnt_default_if_empty() {
-        let cfg_str: &'static str = r#"
-        [book]
-        title = "Some Book"
+    fn use_default_preprocessors_works() {
+        let mut cfg = Config::default();
+        cfg.build.use_default_preprocessors = false;
 
-        [build]
-        build-dir = "outputs"
-        create-missing = false
-        preprocess = []
-        "#;
+        let got = determine_preprocessors(&cfg).unwrap();
 
-        let cfg = Config::from_str(cfg_str).unwrap();
-
-        // make sure we have something in the `output` table
-        assert!(cfg.build.preprocess.is_some());
-
-        let got = determine_preprocessors(&cfg);
-
-        assert!(got.is_ok());
-        assert!(got.unwrap().is_empty());
+        assert_eq!(got.len(), 0);
     }
 
     #[test]
-    fn config_complains_if_unimplemented_preprocessor() {
-        let cfg_str: &'static str = r#"
+    fn can_determine_third_party_preprocessors() {
+        let cfg_str = r#"
         [book]
         title = "Some Book"
 
+        [preprocessor.random]
+
         [build]
         build-dir = "outputs"
         create-missing = false
-        preprocess = ["random"]
         "#;
 
         let cfg = Config::from_str(cfg_str).unwrap();
 
-        // make sure we have something in the `output` table
-        assert!(cfg.build.preprocess.is_some());
+        // make sure the `preprocessor.random` table exists
+        assert!(cfg.get_preprocessor("random").is_some());
 
-        let got = determine_preprocessors(&cfg);
+        let got = determine_preprocessors(&cfg).unwrap();
 
-        assert!(got.is_err());
+        assert!(got.into_iter().any(|p| p.name() == "random"));
+    }
+
+    #[test]
+    fn preprocessors_can_provide_their_own_commands() {
+        let cfg_str = r#"
+        [preprocessor.random]
+        command = "python random.py"
+        "#;
+
+        let cfg = Config::from_str(cfg_str).unwrap();
+
+        // make sure the `preprocessor.random` table exists
+        let random = cfg.get_preprocessor("random").unwrap();
+        let random = interpret_custom_preprocessor("random", &Value::Table(random.clone()));
+
+        assert_eq!(random.cmd(), "python random.py");
+    }
+
+    #[test]
+    fn config_respects_preprocessor_selection() {
+        let cfg_str = r#"
+        [preprocessor.links]
+        renderers = ["html"]
+        "#;
+
+        let cfg = Config::from_str(cfg_str).unwrap();
+
+        // double-check that we can access preprocessor.links.renderers[0]
+        let html = cfg
+            .get_preprocessor("links")
+            .and_then(|links| links.get("renderers"))
+            .and_then(Value::as_array)
+            .and_then(|renderers| renderers.get(0))
+            .and_then(Value::as_str)
+            .unwrap();
+        assert_eq!(html, "html");
+        let html_renderer = HtmlHandlebars::default();
+        let pre = LinkPreprocessor::new();
+
+        let should_run = preprocessor_should_run(&pre, &html_renderer, &cfg);
+        assert!(should_run);
+    }
+
+    struct BoolPreprocessor(bool);
+    impl Preprocessor for BoolPreprocessor {
+        fn name(&self) -> &str {
+            "bool-preprocessor"
+        }
+
+        fn run(&self, _ctx: &PreprocessorContext, _book: Book) -> Result<Book> {
+            unimplemented!()
+        }
+
+        fn supports_renderer(&self, _renderer: &str) -> bool {
+            self.0
+        }
+    }
+
+    #[test]
+    fn preprocessor_should_run_falls_back_to_supports_renderer_method() {
+        let cfg = Config::default();
+        let html = HtmlHandlebars::new();
+
+        let should_be = true;
+        let got = preprocessor_should_run(&BoolPreprocessor(should_be), &html, &cfg);
+        assert_eq!(got, should_be);
+
+        let should_be = false;
+        let got = preprocessor_should_run(&BoolPreprocessor(should_be), &html, &cfg);
+        assert_eq!(got, should_be);
     }
 }

src/book/summary.rs

@@ -1,10 +1,10 @@
+use crate::errors::*;
+use memchr::{self, Memchr};
+use pulldown_cmark::{self, Event, Tag};
 use std::fmt::{self, Display, Formatter};
 use std::iter::FromIterator;
 use std::ops::{Deref, DerefMut};
 use std::path::{Path, PathBuf};
-use memchr::{self, Memchr};
-use pulldown_cmark::{self, Event, Tag};
-use errors::*;
 
 /// Parse the text from a `SUMMARY.md` file into a sort of "recipe" to be
 /// used when loading a book from disk.
@@ -164,37 +164,38 @@ struct SummaryParser<'a> {
 /// use pattern matching and you won't get errors because `take_while()`
 /// moves `$stream` out of self.
 macro_rules! collect_events {
-    ($stream:expr, start $delimiter:pat) => {
+    ($stream:expr,start $delimiter:pat) => {
         collect_events!($stream, Event::Start($delimiter))
     };
-    ($stream:expr, end $delimiter:pat) => {
+    ($stream:expr,end $delimiter:pat) => {
         collect_events!($stream, Event::End($delimiter))
     };
-    ($stream:expr, $delimiter:pat) => {
-        {
-            let mut events = Vec::new();
+    ($stream:expr, $delimiter:pat) => {{
+        let mut events = Vec::new();
 
-            loop {
-                let event = $stream.next();
-                trace!("Next event: {:?}", event);
+        loop {
+            let event = $stream.next();
+            trace!("Next event: {:?}", event);
 
-                match event {
-                    Some($delimiter) => break,
-                    Some(other) => events.push(other),
-                    None => {
-                        debug!("Reached end of stream without finding the closing pattern, {}", stringify!($delimiter));
-                        break;
-                    }
+            match event {
+                Some($delimiter) => break,
+                Some(other) => events.push(other),
+                None => {
+                    debug!(
+                        "Reached end of stream without finding the closing pattern, {}",
+                        stringify!($delimiter)
+                    );
+                    break;
                 }
             }
-
-            events
         }
-    }
+
+        events
+    }};
 }
 
 impl<'a> SummaryParser<'a> {
-    fn new(text: &str) -> SummaryParser {
+    fn new(text: &str) -> SummaryParser<'_> {
         let pulldown_parser = pulldown_cmark::Parser::new(text);
 
         SummaryParser {
@@ -220,11 +221,14 @@ impl<'a> SummaryParser<'a> {
     fn parse(mut self) -> Result<Summary> {
         let title = self.parse_title();
 
-        let prefix_chapters = self.parse_affix(true)
+        let prefix_chapters = self
+            .parse_affix(true)
             .chain_err(|| "There was an error parsing the prefix chapters")?;
-        let numbered_chapters = self.parse_numbered()
+        let numbered_chapters = self
+            .parse_numbered()
             .chain_err(|| "There was an error parsing the numbered chapters")?;
-        let suffix_chapters = self.parse_affix(false)
+        let suffix_chapters = self
+            .parse_affix(false)
             .chain_err(|| "There was an error parsing the suffix chapters")?;
 
         Ok(Summary {
@@ -255,7 +259,7 @@ impl<'a> SummaryParser<'a> {
                         bail!(self.parse_error("Suffix chapters cannot be followed by a list"));
                     }
                 }
-                Some(Event::Start(Tag::Link(href, _))) => {
+                Some(Event::Start(Tag::Link(_type, href, _title))) => {
                     let link = self.parse_link(href.to_string())?;
                     items.push(SummaryItem::Link(link));
                 }
@@ -276,7 +280,7 @@ impl<'a> SummaryParser<'a> {
             Err(self.parse_error("You can't have an empty link."))
         } else {
             Ok(Link {
-                name: name,
+                name,
                 location: PathBuf::from(href.to_string()),
                 number: None,
                 nested_items: Vec::new(),
@@ -288,6 +292,7 @@ impl<'a> SummaryParser<'a> {
     /// already been consumed by a previous parser.
     fn parse_numbered(&mut self) -> Result<Vec<SummaryItem>> {
         let mut items = Vec::new();
+        let mut root_items = 0;
         let root_number = SectionNumber::default();
 
         // we need to do this funny loop-match-if-let dance because a rule will
@@ -304,7 +309,8 @@ impl<'a> SummaryParser<'a> {
             // if we've resumed after something like a rule the root sections
             // will be numbered from 1. We need to manually go back and update
             // them
-            update_section_numbers(&mut bunch_of_items, 0, items.len() as u32);
+            update_section_numbers(&mut bunch_of_items, 0, root_items);
+            root_items += bunch_of_items.len() as u32;
             items.extend(bunch_of_items);
 
             match self.next_event() {
@@ -391,7 +397,7 @@ impl<'a> SummaryParser<'a> {
         loop {
             match self.next_event() {
                 Some(Event::Start(Tag::Paragraph)) => continue,
-                Some(Event::Start(Tag::Link(href, _))) => {
+                Some(Event::Start(Tag::Link(_type, href, _title))) => {
                     let mut link = self.parse_link(href.to_string())?;
 
                     let mut number = parent.clone();
@@ -465,11 +471,11 @@ fn get_last_link(links: &mut [SummaryItem]) -> Result<(usize, &mut Link)> {
 
 /// Removes the styling from a list of Markdown events and returns just the
 /// plain text.
-fn stringify_events(events: Vec<Event>) -> String {
+fn stringify_events(events: Vec<Event<'_>>) -> String {
     events
         .into_iter()
         .filter_map(|t| match t {
-            Event::Text(text) => Some(text.into_owned()),
+            Event::Text(text) | Event::Code(text) => Some(text.into_string()),
             _ => None,
         })
         .collect()
@@ -481,7 +487,7 @@ fn stringify_events(events: Vec<Event>) -> String {
 pub struct SectionNumber(pub Vec<u32>);
 
 impl Display for SectionNumber {
-    fn fmt(&self, f: &mut Formatter) -> fmt::Result {
+    fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
         if self.0.is_empty() {
             write!(f, "0")
         } else {
@@ -623,7 +629,7 @@ mod tests {
         let _ = parser.stream.next(); // skip past start of paragraph
 
         let href = match parser.stream.next() {
-            Some(Event::Start(Tag::Link(href, _))) => href.to_string(),
+            Some(Event::Start(Tag::Link(_type, href, _title))) => href.to_string(),
             other => panic!("Unreachable, {:?}", other),
         };
 
@@ -659,14 +665,12 @@ mod tests {
                 name: String::from("First"),
                 location: PathBuf::from("./first.md"),
                 number: Some(SectionNumber(vec![1])),
-                nested_items: vec![
-                    SummaryItem::Link(Link {
-                        name: String::from("Nested"),
-                        location: PathBuf::from("./nested.md"),
-                        number: Some(SectionNumber(vec![1, 1])),
-                        nested_items: Vec::new(),
-                    }),
-                ],
+                nested_items: vec![SummaryItem::Link(Link {
+                    name: String::from("Nested"),
+                    location: PathBuf::from("./nested.md"),
+                    number: Some(SectionNumber(vec![1, 1])),
+                    nested_items: Vec::new(),
+                })],
             }),
             SummaryItem::Link(Link {
                 name: String::from("Second"),
@@ -723,4 +727,41 @@ mod tests {
         let got = parser.parse_numbered();
         assert!(got.is_err());
     }
+
+    /// Regression test for https://github.com/rust-lang-nursery/mdBook/issues/779
+    /// Ensure section numbers are correctly incremented after a horizontal separator.
+    #[test]
+    fn keep_numbering_after_separator() {
+        let src =
+            "- [First](./first.md)\n---\n- [Second](./second.md)\n---\n- [Third](./third.md)\n";
+        let should_be = vec![
+            SummaryItem::Link(Link {
+                name: String::from("First"),
+                location: PathBuf::from("./first.md"),
+                number: Some(SectionNumber(vec![1])),
+                nested_items: Vec::new(),
+            }),
+            SummaryItem::Separator,
+            SummaryItem::Link(Link {
+                name: String::from("Second"),
+                location: PathBuf::from("./second.md"),
+                number: Some(SectionNumber(vec![2])),
+                nested_items: Vec::new(),
+            }),
+            SummaryItem::Separator,
+            SummaryItem::Link(Link {
+                name: String::from("Third"),
+                location: PathBuf::from("./third.md"),
+                number: Some(SectionNumber(vec![3])),
+                nested_items: Vec::new(),
+            }),
+        ];
+
+        let mut parser = SummaryParser::new(src);
+        let _ = parser.stream.next();
+
+        let got = parser.parse_numbered().unwrap();
+
+        assert_eq!(got, should_be);
+    }
 }

src/cmd/build.rs

@@ -1,21 +1,22 @@
-use std::path::PathBuf;
+use crate::{get_book_dir, open};
 use clap::{App, ArgMatches, SubCommand};
-use mdbook::MDBook;
 use mdbook::errors::Result;
-use {get_book_dir, open};
+use mdbook::MDBook;
 
 // Create clap subcommand arguments
 pub fn make_subcommand<'a, 'b>() -> App<'a, 'b> {
     SubCommand::with_name("build")
-        .about("Build the book from the markdown files")
-        .arg_from_usage("-o, --open 'Open the compiled book in a web browser'")
+        .about("Builds a book from its markdown files")
         .arg_from_usage(
-            "-d, --dest-dir=[dest-dir] 'The output directory for your book{n}(Defaults to ./book \
-             when omitted)'",
+            "-d, --dest-dir=[dest-dir] 'Output directory for the book{n}\
+             Relative paths are interpreted relative to the book's root directory.{n}\
+             If omitted, mdBook uses build.build-dir from book.toml or defaults to `./book`.'",
         )
         .arg_from_usage(
-            "[dir] 'A directory for your book{n}(Defaults to Current Directory when omitted)'",
+            "[dir] 'Root directory for the book{n}\
+             (Defaults to the Current Directory when omitted)'",
         )
+        .arg_from_usage("-o, --open 'Opens the compiled book in a web browser'")
 }
 
 // Build command implementation
@@ -24,7 +25,7 @@ pub fn execute(args: &ArgMatches) -> Result<()> {
     let mut book = MDBook::load(&book_dir)?;
 
     if let Some(dest_dir) = args.value_of("dest-dir") {
-        book.config.build.build_dir = PathBuf::from(dest_dir);
+        book.config.build.build_dir = dest_dir.into();
     }
 
     book.build()?;

src/cmd/clean.rs

@@ -0,0 +1,38 @@
+use crate::get_book_dir;
+use clap::{App, ArgMatches, SubCommand};
+use mdbook::errors::*;
+use mdbook::MDBook;
+use std::fs;
+
+// Create clap subcommand arguments
+pub fn make_subcommand<'a, 'b>() -> App<'a, 'b> {
+    SubCommand::with_name("clean")
+        .about("Deletes a built book")
+        .arg_from_usage(
+            "-d, --dest-dir=[dest-dir] 'Output directory for the book{n}\
+             Relative paths are interpreted relative to the book's root directory.{n}\
+             Running this command deletes this directory.{n}\
+             If omitted, mdBook uses build.build-dir from book.toml or defaults to `./book`.'",
+        )
+        .arg_from_usage(
+            "[dir] 'Root directory for the book{n}\
+             (Defaults to the Current Directory when omitted)'",
+        )
+}
+
+// Clean command implementation
+pub fn execute(args: &ArgMatches) -> mdbook::errors::Result<()> {
+    let book_dir = get_book_dir(args);
+    let book = MDBook::load(&book_dir)?;
+
+    let dir_to_remove = match args.value_of("dest-dir") {
+        Some(dest_dir) => dest_dir.into(),
+        None => book.root.join(&book.config.build.build_dir),
+    };
+
+    if dir_to_remove.exists() {
+        fs::remove_dir_all(&dir_to_remove).chain_err(|| "Unable to remove the build directory")?;
+    }
+
+    Ok(())
+}

src/cmd/init.rs

@@ -1,21 +1,23 @@
+use crate::get_book_dir;
+use clap::{App, ArgMatches, SubCommand};
+use mdbook::config;
+use mdbook::errors::Result;
+use mdbook::MDBook;
 use std::io;
 use std::io::Write;
 use std::process::Command;
-use clap::{App, ArgMatches, SubCommand};
-use mdbook::MDBook;
-use mdbook::errors::Result;
-use mdbook::config;
-use get_book_dir;
 
 // Create clap subcommand arguments
 pub fn make_subcommand<'a, 'b>() -> App<'a, 'b> {
     SubCommand::with_name("init")
-        .about("Create boilerplate structure and files in the directory")
+        .about("Creates the boilerplate structure and files for a new book")
         // the {n} denotes a newline which will properly aligned in all help messages
-        .arg_from_usage("[dir] 'A directory for your book{n}(Defaults to Current Directory \
-                         when omitted)'")
+        .arg_from_usage(
+            "[dir] 'Directory to create the book in{n}\
+             (Defaults to the Current Directory when omitted)'",
+        )
         .arg_from_usage("--theme 'Copies the default theme into your source folder'")
-        .arg_from_usage("--force 'skip confirmation prompts'")
+        .arg_from_usage("--force 'Skips confirmation prompts'")
 }
 
 // Init command implementation

src/cmd/mod.rs

@@ -0,0 +1,10 @@
+//! Subcommand modules for the `mdbook` binary.
+
+pub mod build;
+pub mod clean;
+pub mod init;
+#[cfg(feature = "serve")]
+pub mod serve;
+pub mod test;
+#[cfg(feature = "watch")]
+pub mod watch;

src/cmd/serve.rs

@@ -0,0 +1,144 @@
+#[cfg(feature = "watch")]
+use super::watch;
+use crate::{get_book_dir, open};
+use clap::{App, Arg, ArgMatches, SubCommand};
+use iron::{status, AfterMiddleware, Chain, Iron, IronError, IronResult, Request, Response, Set};
+use mdbook::errors::*;
+use mdbook::utils;
+use mdbook::MDBook;
+
+struct ErrorRecover;
+
+// Create clap subcommand arguments
+pub fn make_subcommand<'a, 'b>() -> App<'a, 'b> {
+    SubCommand::with_name("serve")
+        .about("Serves a book at http://localhost:3000, and rebuilds it on changes")
+        .arg_from_usage(
+            "-d, --dest-dir=[dest-dir] 'Output directory for the book{n}\
+             Relative paths are interpreted relative to the book's root directory.{n}\
+             If omitted, mdBook uses build.build-dir from book.toml or defaults to `./book`.'",
+        )
+        .arg_from_usage(
+            "[dir] 'Root directory for the book{n}\
+             (Defaults to the Current Directory when omitted)'",
+        )
+        .arg(
+            Arg::with_name("hostname")
+                .short("n")
+                .long("hostname")
+                .takes_value(true)
+                .default_value("localhost")
+                .empty_values(false)
+                .help("Hostname to listen on for HTTP connections"),
+        )
+        .arg(
+            Arg::with_name("port")
+                .short("p")
+                .long("port")
+                .takes_value(true)
+                .default_value("3000")
+                .empty_values(false)
+                .help("Port to use for HTTP connections"),
+        )
+        .arg(
+            Arg::with_name("websocket-hostname")
+                .long("websocket-hostname")
+                .takes_value(true)
+                .empty_values(false)
+                .help(
+                    "Hostname to connect to for WebSockets connections (Defaults to the HTTP hostname)",
+                ),
+        )
+        .arg(
+            Arg::with_name("websocket-port")
+                .short("w")
+                .long("websocket-port")
+                .takes_value(true)
+                .default_value("3001")
+                .empty_values(false)
+                .help("Port to use for WebSockets livereload connections"),
+        )
+        .arg_from_usage("-o, --open 'Opens the book server in a web browser'")
+}
+
+// Watch command implementation
+pub fn execute(args: &ArgMatches) -> Result<()> {
+    let book_dir = get_book_dir(args);
+    let mut book = MDBook::load(&book_dir)?;
+
+    let port = args.value_of("port").unwrap();
+    let ws_port = args.value_of("websocket-port").unwrap();
+    let hostname = args.value_of("hostname").unwrap();
+    let public_address = args.value_of("websocket-hostname").unwrap_or(hostname);
+    let open_browser = args.is_present("open");
+
+    let address = format!("{}:{}", hostname, port);
+    let ws_address = format!("{}:{}", hostname, ws_port);
+
+    let livereload_url = format!("ws://{}:{}", public_address, ws_port);
+    book.config
+        .set("output.html.livereload-url", &livereload_url)?;
+
+    if let Some(dest_dir) = args.value_of("dest-dir") {
+        book.config.build.build_dir = dest_dir.into();
+    }
+
+    book.build()?;
+
+    let mut chain = Chain::new(staticfile::Static::new(book.build_dir_for("html")));
+    chain.link_after(ErrorRecover);
+    let _iron = Iron::new(chain)
+        .http(&*address)
+        .chain_err(|| "Unable to launch the server")?;
+
+    let ws_server =
+        ws::WebSocket::new(|_| |_| Ok(())).chain_err(|| "Unable to start the websocket")?;
+
+    let broadcaster = ws_server.broadcaster();
+
+    std::thread::spawn(move || {
+        ws_server.listen(&*ws_address).unwrap();
+    });
+
+    let serving_url = format!("http://{}", address);
+    info!("Serving on: {}", serving_url);
+
+    if open_browser {
+        open(serving_url);
+    }
+
+    #[cfg(feature = "watch")]
+    watch::trigger_on_change(&book, move |paths, book_dir| {
+        info!("Files changed: {:?}", paths);
+        info!("Building book...");
+
+        // FIXME: This area is really ugly because we need to re-set livereload :(
+
+        let result = MDBook::load(&book_dir)
+            .and_then(|mut b| {
+                b.config
+                    .set("output.html.livereload-url", &livereload_url)?;
+                Ok(b)
+            })
+            .and_then(|b| b.build());
+
+        if let Err(e) = result {
+            error!("Unable to load the book");
+            utils::log_backtrace(&e);
+        } else {
+            let _ = broadcaster.send("reload");
+        }
+    });
+
+    Ok(())
+}
+
+impl AfterMiddleware for ErrorRecover {
+    fn catch(&self, _: &mut Request, err: IronError) -> IronResult<Response> {
+        match err.response.status {
+            // each error will result in 404 response
+            Some(_) => Ok(err.response.set(status::NotFound)),
+            _ => Err(err),
+        }
+    }
+}

src/cmd/test.rs

@@ -0,0 +1,46 @@
+use crate::get_book_dir;
+use clap::{App, Arg, ArgMatches, SubCommand};
+use mdbook::errors::Result;
+use mdbook::MDBook;
+
+// Create clap subcommand arguments
+pub fn make_subcommand<'a, 'b>() -> App<'a, 'b> {
+    SubCommand::with_name("test")
+        .about("Tests that a book's Rust code samples compile")
+        .arg_from_usage(
+            "-d, --dest-dir=[dest-dir] 'Output directory for the book{n}\
+             Relative paths are interpreted relative to the book's root directory.{n}\
+             If omitted, mdBook uses build.build-dir from book.toml or defaults to `./book`.'",
+        )
+        .arg_from_usage(
+            "[dir] 'Root directory for the book{n}\
+             (Defaults to the Current Directory when omitted)'",
+        )
+        .arg(Arg::with_name("library-path")
+            .short("L")
+            .long("library-path")
+            .value_name("dir")
+            .takes_value(true)
+            .require_delimiter(true)
+            .multiple(true)
+            .empty_values(false)
+            .help("A comma-separated list of directories to add to {n}the crate search path when building tests"))
+}
+
+// test command implementation
+pub fn execute(args: &ArgMatches) -> Result<()> {
+    let library_paths: Vec<&str> = args
+        .values_of("library-path")
+        .map(std::iter::Iterator::collect)
+        .unwrap_or_default();
+    let book_dir = get_book_dir(args);
+    let mut book = MDBook::load(&book_dir)?;
+
+    if let Some(dest_dir) = args.value_of("dest-dir") {
+        book.config.build.build_dir = dest_dir.into();
+    }
+
+    book.test(library_paths)?;
+
+    Ok(())
+}

src/cmd/watch.rs

@@ -0,0 +1,154 @@
+use crate::{get_book_dir, open};
+use clap::{App, ArgMatches, SubCommand};
+use mdbook::errors::Result;
+use mdbook::utils;
+use mdbook::MDBook;
+use notify::Watcher;
+use std::path::{Path, PathBuf};
+use std::sync::mpsc::channel;
+use std::thread::sleep;
+use std::time::Duration;
+
+// Create clap subcommand arguments
+pub fn make_subcommand<'a, 'b>() -> App<'a, 'b> {
+    SubCommand::with_name("watch")
+        .about("Watches a book's files and rebuilds it on changes")
+        .arg_from_usage(
+            "-d, --dest-dir=[dest-dir] 'Output directory for the book{n}\
+             Relative paths are interpreted relative to the book's root directory.{n}\
+             If omitted, mdBook uses build.build-dir from book.toml or defaults to `./book`.'",
+        )
+        .arg_from_usage(
+            "[dir] 'Root directory for the book{n}\
+             (Defaults to the Current Directory when omitted)'",
+        )
+        .arg_from_usage("-o, --open 'Open the compiled book in a web browser'")
+}
+
+// Watch command implementation
+pub fn execute(args: &ArgMatches) -> Result<()> {
+    let book_dir = get_book_dir(args);
+    let book = MDBook::load(&book_dir)?;
+
+    if args.is_present("open") {
+        book.build()?;
+        open(book.build_dir_for("html").join("index.html"));
+    }
+
+    trigger_on_change(&book, |paths, book_dir| {
+        info!("Files changed: {:?}\nBuilding book...\n", paths);
+        let result = MDBook::load(&book_dir).and_then(|b| b.build());
+
+        if let Err(e) = result {
+            error!("Unable to build the book");
+            utils::log_backtrace(&e);
+        }
+    });
+
+    Ok(())
+}
+
+fn remove_ignored_files(book_root: &PathBuf, paths: &[PathBuf]) -> Vec<PathBuf> {
+    if paths.is_empty() {
+        return vec![];
+    }
+
+    match find_gitignore(book_root) {
+        Some(gitignore_path) => {
+            match gitignore::File::new(gitignore_path.as_path()) {
+                Ok(exclusion_checker) => filter_ignored_files(exclusion_checker, paths),
+                Err(_) => {
+                    // We're unable to read the .gitignore file, so we'll silently allow everything.
+                    // Please see discussion: https://github.com/rust-lang-nursery/mdBook/pull/1051
+                    paths.iter().map(|path| path.to_path_buf()).collect()
+                }
+            }
+        }
+        None => {
+            // There is no .gitignore file.
+            paths.iter().map(|path| path.to_path_buf()).collect()
+        }
+    }
+}
+
+fn find_gitignore(book_root: &PathBuf) -> Option<PathBuf> {
+    book_root
+        .ancestors()
+        .map(|p| p.join(".gitignore"))
+        .find(|p| p.exists())
+}
+
+fn filter_ignored_files(exclusion_checker: gitignore::File, paths: &[PathBuf]) -> Vec<PathBuf> {
+    paths
+        .iter()
+        .filter(|path| match exclusion_checker.is_excluded(path) {
+            Ok(exclude) => !exclude,
+            Err(error) => {
+                warn!(
+                    "Unable to determine if {:?} is excluded: {:?}. Including it.",
+                    &path, error
+                );
+                true
+            }
+        })
+        .map(|path| path.to_path_buf())
+        .collect()
+}
+
+/// Calls the closure when a book source file is changed, blocking indefinitely.
+pub fn trigger_on_change<F>(book: &MDBook, closure: F)
+where
+    F: Fn(Vec<PathBuf>, &Path),
+{
+    use notify::DebouncedEvent::*;
+    use notify::RecursiveMode::*;
+
+    // Create a channel to receive the events.
+    let (tx, rx) = channel();
+
+    let mut watcher = match notify::watcher(tx, Duration::from_secs(1)) {
+        Ok(w) => w,
+        Err(e) => {
+            error!("Error while trying to watch the files:\n\n\t{:?}", e);
+            std::process::exit(1)
+        }
+    };
+
+    // Add the source directory to the watcher
+    if let Err(e) = watcher.watch(book.source_dir(), Recursive) {
+        error!("Error while watching {:?}:\n    {:?}", book.source_dir(), e);
+        std::process::exit(1);
+    };
+
+    let _ = watcher.watch(book.theme_dir(), Recursive);
+
+    // Add the book.toml file to the watcher if it exists
+    let _ = watcher.watch(book.root.join("book.toml"), NonRecursive);
+
+    info!("Listening for changes...");
+
+    loop {
+        let first_event = rx.recv().unwrap();
+        sleep(Duration::from_millis(50));
+        let other_events = rx.try_iter();
+
+        let all_events = std::iter::once(first_event).chain(other_events);
+
+        let paths = all_events
+            .filter_map(|event| {
+                debug!("Received filesystem event: {:?}", event);
+
+                match event {
+                    Create(path) | Write(path) | Remove(path) | Rename(_, path) => Some(path),
+                    _ => None,
+                }
+            })
+            .collect::<Vec<_>>();
+
+        let paths = remove_ignored_files(&book.root, &paths[..]);
+
+        if !paths.is_empty() {
+            closure(paths, &book.root);
+        }
+    }
+}

src/config.rs

@@ -3,16 +3,15 @@
 //! The main entrypoint of the `config` module is the `Config` struct. This acts
 //! essentially as a bag of configuration information, with a couple
 //! pre-determined tables (`BookConfig` and `BuildConfig`) as well as support
-//! for arbitrary data which is exposed to plugins and alternate backends.
+//! for arbitrary data which is exposed to plugins and alternative backends.
 //!
 //!
 //! # Examples
 //!
 //! ```rust
-//! # extern crate mdbook;
 //! # use mdbook::errors::*;
-//! # extern crate toml;
 //! use std::path::PathBuf;
+//! use std::str::FromStr;
 //! use mdbook::Config;
 //! use toml::Value;
 //!
@@ -41,8 +40,8 @@
 //! cfg.set("output.html.theme", "./themes");
 //!
 //! // then load it again, automatically deserializing to a `PathBuf`.
-//! let got: PathBuf = cfg.get_deserialized("output.html.theme")?;
-//! assert_eq!(got, PathBuf::from("./themes"));
+//! let got: Option<PathBuf> = cfg.get_deserialized_opt("output.html.theme")?;
+//! assert_eq!(got, Some(PathBuf::from("./themes")));
 //! # Ok(())
 //! # }
 //! # fn main() { run().unwrap() }
@@ -50,19 +49,20 @@
 
 #![deny(missing_docs)]
 
-use std::path::{Path, PathBuf};
+use serde::{Deserialize, Deserializer, Serialize, Serializer};
+use std::env;
 use std::fs::File;
 use std::io::Read;
-use std::env;
-use toml::{self, Value};
+use std::path::{Path, PathBuf};
+use std::str::FromStr;
 use toml::value::Table;
-use toml_query::read::TomlValueReadExt;
-use toml_query::insert::TomlValueInsertExt;
+use toml::{self, Value};
 use toml_query::delete::TomlValueDeleteExt;
-use serde::{Deserialize, Deserializer, Serialize, Serializer};
-use serde_json;
+use toml_query::insert::TomlValueInsertExt;
+use toml_query::read::TomlValueReadExt;
 
-use errors::*;
+use crate::errors::*;
+use crate::utils;
 
 /// The overall configuration object for MDBook, essentially an in-memory
 /// representation of `book.toml`.
@@ -75,12 +75,16 @@ pub struct Config {
     rest: Value,
 }
 
-impl Config {
+impl FromStr for Config {
+    type Err = Error;
+
     /// Load a `Config` from some string.
-    pub fn from_str(src: &str) -> Result<Config> {
+    fn from_str(src: &str) -> Result<Self> {
         toml::from_str(src).chain_err(|| Error::from("Invalid configuration file"))
     }
+}
 
+impl Config {
     /// Load the configuration file from disk.
     pub fn from_disk<P: AsRef<Path>>(config_file: P) -> Result<Config> {
         let mut buffer = String::new();
@@ -128,10 +132,8 @@ impl Config {
     pub fn update_from_env(&mut self) {
         debug!("Updating the config from environment variables");
 
-        let overrides = env::vars().filter_map(|(key, value)| match parse_env(&key) {
-            Some(index) => Some((index, value)),
-            None => None,
-        });
+        let overrides =
+            env::vars().filter_map(|(key, value)| parse_env(&key).map(|index| (index, value)));
 
         for (key, value) in overrides {
             trace!("{} => {}", key, value);
@@ -148,14 +150,11 @@ impl Config {
     /// `output.html.playpen` will fetch the "playpen" out of the html output
     /// table).
     pub fn get(&self, key: &str) -> Option<&Value> {
-        match self.rest.read(key) {
-            Ok(inner) => inner,
-            Err(_) => None,
-        }
+        self.rest.read(key).unwrap_or(None)
     }
 
     /// Fetch a value from the `Config` so you can mutate it.
-    pub fn get_mut<'a>(&'a mut self, key: &str) -> Option<&'a mut Value> {
+    pub fn get_mut(&mut self, key: &str) -> Option<&mut Value> {
         match self.rest.read_mut(key) {
             Ok(inner) => inner,
             Err(_) => None,
@@ -170,22 +169,41 @@ impl Config {
     /// HTML renderer is refactored to be less coupled to `mdbook` internals.
     #[doc(hidden)]
     pub fn html_config(&self) -> Option<HtmlConfig> {
-        self.get_deserialized("output.html").ok()
+        match self.get_deserialized_opt("output.html") {
+            Ok(Some(config)) => Some(config),
+            Ok(None) => None,
+            Err(e) => {
+                utils::log_backtrace(&e.chain_err(|| "Parsing configuration [output.html]"));
+                None
+            }
+        }
+    }
+
+    /// Deprecated, use get_deserialized_opt instead.
+    #[deprecated = "use get_deserialized_opt instead"]
+    pub fn get_deserialized<'de, T: Deserialize<'de>, S: AsRef<str>>(&self, name: S) -> Result<T> {
+        let name = name.as_ref();
+        match self.get_deserialized_opt(name)? {
+            Some(value) => Ok(value),
+            None => bail!("Key not found, {:?}", name),
+        }
     }
 
     /// Convenience function to fetch a value from the config and deserialize it
     /// into some arbitrary type.
-    pub fn get_deserialized<'de, T: Deserialize<'de>, S: AsRef<str>>(&self, name: S) -> Result<T> {
+    pub fn get_deserialized_opt<'de, T: Deserialize<'de>, S: AsRef<str>>(
+        &self,
+        name: S,
+    ) -> Result<Option<T>> {
         let name = name.as_ref();
-
-        if let Some(value) = self.get(name) {
-            value
-                .clone()
-                .try_into()
-                .chain_err(|| "Couldn't deserialize the value")
-        } else {
-            bail!("Key not found, {:?}", name)
-        }
+        self.get(name)
+            .map(|value| {
+                value
+                    .clone()
+                    .try_into()
+                    .chain_err(|| "Couldn't deserialize the value")
+            })
+            .transpose()
     }
 
     /// Set a config key, clobbering any existing values along the way.
@@ -203,12 +221,26 @@ impl Config {
         } else if index.starts_with("build.") {
             self.build.update_value(&index[6..], value);
         } else {
-            self.rest.insert(index, value)?;
+            self.rest
+                .insert(index, value)
+                .map_err(ErrorKind::TomlQueryError)?;
         }
 
         Ok(())
     }
 
+    /// Get the table associated with a particular renderer.
+    pub fn get_renderer<I: AsRef<str>>(&self, index: I) -> Option<&Table> {
+        let key = format!("output.{}", index.as_ref());
+        self.get(&key).and_then(Value::as_table)
+    }
+
+    /// Get the table associated with a particular preprocessor.
+    pub fn get_preprocessor<I: AsRef<str>>(&self, index: I) -> Option<&Table> {
+        let key = format!("preprocessor.{}", index.as_ref());
+        self.get(&key).and_then(Value::as_table)
+    }
+
     fn from_legacy(mut table: Value) -> Config {
         let mut cfg = Config::default();
 
@@ -217,9 +249,10 @@ impl Config {
         // figure out what try_into() deserializes to.
         macro_rules! get_and_insert {
             ($table:expr, $key:expr => $out:expr) => {
-                let got = $table.as_table_mut()
-                                .and_then(|t| t.remove($key))
-                                .and_then(|v| v.try_into().ok());
+                let got = $table
+                    .as_table_mut()
+                    .and_then(|t| t.remove($key))
+                    .and_then(|v| v.try_into().ok());
                 if let Some(value) = got {
                     $out = value;
                 }
@@ -252,7 +285,7 @@ impl Default for Config {
     }
 }
 impl<'de> Deserialize<'de> for Config {
-    fn deserialize<D: Deserializer<'de>>(de: D) -> ::std::result::Result<Self, D::Error> {
+    fn deserialize<D: Deserializer<'de>>(de: D) -> std::result::Result<Self, D::Error> {
         let raw = Value::deserialize(de)?;
 
         if is_legacy_format(&raw) {
@@ -288,15 +321,15 @@ impl<'de> Deserialize<'de> for Config {
             .unwrap_or_default();
 
         Ok(Config {
-            book: book,
-            build: build,
+            book,
+            build,
             rest: Value::Table(table),
         })
     }
 }
 
 impl Serialize for Config {
-    fn serialize<S: Serializer>(&self, s: S) -> ::std::result::Result<S::Ok, S::Error> {
+    fn serialize<S: Serializer>(&self, s: S) -> std::result::Result<S::Ok, S::Error> {
         use serde::ser::Error;
 
         let mut table = self.rest.clone();
@@ -358,6 +391,8 @@ pub struct BookConfig {
     pub src: PathBuf,
     /// Does this book support more than one language?
     pub multilingual: bool,
+    /// The main language of the book.
+    pub language: Option<String>,
 }
 
 impl Default for BookConfig {
@@ -368,6 +403,7 @@ impl Default for BookConfig {
             description: None,
             src: PathBuf::from("src"),
             multilingual: false,
+            language: Some(String::from("en")),
         }
     }
 }
@@ -381,8 +417,9 @@ pub struct BuildConfig {
     /// Should non-existent markdown files specified in `SETTINGS.md` be created
     /// if they don't exist?
     pub create_missing: bool,
-    /// Which preprocessors should be applied
-    pub preprocess: Option<Vec<String>>,
+    /// Should the default preprocessors always be used when they are
+    /// compatible with the renderer?
+    pub use_default_preprocessors: bool,
 }
 
 impl Default for BuildConfig {
@@ -390,7 +427,7 @@ impl Default for BuildConfig {
         BuildConfig {
             build_dir: PathBuf::from("book"),
             create_missing: true,
-            preprocess: None,
+            use_default_preprocessors: true,
         }
     }
 }
@@ -401,6 +438,11 @@ impl Default for BuildConfig {
 pub struct HtmlConfig {
     /// The theme directory, if specified.
     pub theme: Option<PathBuf>,
+    /// The default theme to use, defaults to 'light'
+    pub default_theme: Option<String>,
+    /// The theme to use if the browser requests the dark version of the site.
+    /// Defaults to the same as 'default_theme'
+    pub preferred_dark_theme: Option<String>,
     /// Use "smart quotes" instead of the usual `"` character.
     pub curly_quotes: bool,
     /// Should mathjax be enabled?
@@ -412,8 +454,19 @@ pub struct HtmlConfig {
     /// Additional JS scripts to include at the bottom of the rendered page's
     /// `<body>`.
     pub additional_js: Vec<PathBuf>,
+    /// Fold settings.
+    pub fold: Fold,
     /// Playpen settings.
     pub playpen: Playpen,
+    /// Don't render section labels.
+    pub no_section_label: bool,
+    /// Search settings. If `None`, the default will be used.
+    pub search: Option<Search>,
+    /// Git repository url. If `None`, the git button will not be shown.
+    pub git_repository_url: Option<String>,
+    /// FontAwesome icon class to use for the Git repository link.
+    /// Defaults to `fa-github` if `None`.
+    pub git_repository_icon: Option<String>,
     /// This is used as a bit of a workaround for the `mdbook serve` command.
     /// Basically, because you set the websocket port from the command line, the
     /// `mdbook serve` command needs a way to let the HTML renderer know where
@@ -422,10 +475,6 @@ pub struct HtmlConfig {
     /// This config item *should not be edited* by the end user.
     #[doc(hidden)]
     pub livereload_url: Option<String>,
-    /// Should section labels be rendered?
-    pub no_section_label: bool,
-    /// Search settings. If `None`, the default will be used.
-    pub search: Option<Search>,
 }
 
 impl HtmlConfig {
@@ -439,22 +488,40 @@ impl HtmlConfig {
     }
 }
 
+/// Configuration for how to fold chapters of sidebar.
+#[derive(Default, Debug, Clone, PartialEq, Serialize, Deserialize)]
+#[serde(default, rename_all = "kebab-case")]
+pub struct Fold {
+    /// When off, all folds are open. Default: `false`.
+    pub enable: bool,
+    /// The higher the more folded regions are open. When level is 0, all folds
+    /// are closed.
+    /// Default: `0`.
+    pub level: u8,
+}
+
 /// Configuration for tweaking how the the HTML renderer handles the playpen.
 #[derive(Debug, Clone, PartialEq, Serialize, Deserialize)]
 #[serde(default, rename_all = "kebab-case")]
 pub struct Playpen {
     /// Should playpen snippets be editable? Default: `false`.
     pub editable: bool,
+    /// Display the copy button. Default: `true`.
+    pub copyable: bool,
     /// Copy JavaScript files for the editor to the output directory?
     /// Default: `true`.
     pub copy_js: bool,
+    /// Display line numbers on playpen snippets. Default: `false`.
+    pub line_numbers: bool,
 }
 
 impl Default for Playpen {
     fn default() -> Playpen {
         Playpen {
             editable: false,
+            copyable: true,
             copy_js: true,
+            line_numbers: false,
         }
     }
 }
@@ -463,12 +530,14 @@ impl Default for Playpen {
 #[derive(Debug, Clone, PartialEq, Serialize, Deserialize)]
 #[serde(default, rename_all = "kebab-case")]
 pub struct Search {
+    /// Enable the search feature. Default: `true`.
+    pub enable: bool,
     /// Maximum number of visible results. Default: `30`.
     pub limit_results: u32,
-    /// The number of words used for a search result teaser. Default: `30`,
+    /// The number of words used for a search result teaser. Default: `30`.
     pub teaser_word_count: u32,
     /// Define the logical link between multiple search words.
-    /// If true, all search words must appear in each result. Default: `true`.
+    /// If true, all search words must appear in each result. Default: `false`.
     pub use_boolean_and: bool,
     /// Boost factor for the search result score if a search word appears in the header.
     /// Default: `2`.
@@ -494,6 +563,7 @@ impl Default for Search {
     fn default() -> Search {
         // Please update the documentation of `Search` when changing values!
         Search {
+            enable: true,
             limit_results: 30,
             teaser_word_count: 30,
             use_boolean_and: false,
@@ -516,12 +586,10 @@ trait Updateable<'de>: Serialize + Deserialize<'de> {
     fn update_value<S: Serialize>(&mut self, key: &str, value: S) {
         let mut raw = Value::try_from(&self).expect("unreachable");
 
-        {
-            if let Ok(value) = Value::try_from(value) {
-                let _ = raw.insert(key, value);
-            } else {
-                return;
-            }
+        if let Ok(value) = Value::try_from(value) {
+            let _ = raw.insert(key, value);
+        } else {
+            return;
         }
 
         if let Ok(updated) = raw.try_into() {
@@ -530,38 +598,42 @@ trait Updateable<'de>: Serialize + Deserialize<'de> {
     }
 }
 
-impl<'de, T> Updateable<'de> for T
-where
-    T: Serialize + Deserialize<'de>,
-{
-}
+impl<'de, T> Updateable<'de> for T where T: Serialize + Deserialize<'de> {}
 
 #[cfg(test)]
 mod tests {
     use super::*;
 
-    const COMPLEX_CONFIG: &'static str = r#"
+    const COMPLEX_CONFIG: &str = r#"
         [book]
         title = "Some Book"
         authors = ["Michael-F-Bryan <michaelfbryan@gmail.com>"]
         description = "A completely useless book"
         multilingual = true
         src = "source"
+        language = "ja"
 
         [build]
         build-dir = "outputs"
         create-missing = false
-        preprocess = ["first_preprocessor", "second_preprocessor"]
+        use-default-preprocessors = true
 
         [output.html]
         theme = "./themedir"
+        default-theme = "rust"
         curly-quotes = true
         google-analytics = "123456"
         additional-css = ["./foo/bar/baz.css"]
+        git-repository-url = "https://foo.com/"
+        git-repository-icon = "fa-code-fork"
 
         [output.html.playpen]
         editable = true
         editor = "ace"
+
+        [preprocessor.first]
+
+        [preprocessor.second]
         "#;
 
     #[test]
@@ -574,26 +646,28 @@ mod tests {
             description: Some(String::from("A completely useless book")),
             multilingual: true,
             src: PathBuf::from("source"),
-            ..Default::default()
+            language: Some(String::from("ja")),
         };
         let build_should_be = BuildConfig {
             build_dir: PathBuf::from("outputs"),
             create_missing: false,
-            preprocess: Some(vec![
-                "first_preprocessor".to_string(),
-                "second_preprocessor".to_string(),
-            ]),
+            use_default_preprocessors: true,
         };
         let playpen_should_be = Playpen {
             editable: true,
+            copyable: true,
             copy_js: true,
+            line_numbers: false,
         };
         let html_should_be = HtmlConfig {
             curly_quotes: true,
             google_analytics: Some(String::from("123456")),
             additional_css: vec![PathBuf::from("./foo/bar/baz.css")],
             theme: Some(PathBuf::from("./themedir")),
+            default_theme: Some(String::from("rust")),
             playpen: playpen_should_be,
+            git_repository_url: Some(String::from("https://foo.com/")),
+            git_repository_icon: Some(String::from("fa-code-fork")),
             ..Default::default()
         };
 
@@ -627,14 +701,17 @@ mod tests {
         };
 
         let cfg = Config::from_str(src).unwrap();
-        let got: RandomOutput = cfg.get_deserialized("output.random").unwrap();
+        let got: RandomOutput = cfg.get_deserialized_opt("output.random").unwrap().unwrap();
 
         assert_eq!(got, should_be);
 
-        let baz: Vec<bool> = cfg.get_deserialized("output.random.baz").unwrap();
+        let got_baz: Vec<bool> = cfg
+            .get_deserialized_opt("output.random.baz")
+            .unwrap()
+            .unwrap();
         let baz_should_be = vec![true, true, false];
 
-        assert_eq!(baz, baz_should_be);
+        assert_eq!(got_baz, baz_should_be);
     }
 
     #[test]
@@ -684,7 +761,7 @@ mod tests {
         let build_should_be = BuildConfig {
             build_dir: PathBuf::from("my-book"),
             create_missing: true,
-            preprocess: None,
+            use_default_preprocessors: true,
         };
 
         let html_should_be = HtmlConfig {
@@ -711,7 +788,7 @@ mod tests {
         assert!(cfg.get(key).is_none());
         cfg.set(key, value).unwrap();
 
-        let got: String = cfg.get_deserialized(key).unwrap();
+        let got: String = cfg.get_deserialized_opt(key).unwrap().unwrap();
         assert_eq!(got, value);
     }
 
@@ -726,7 +803,7 @@ mod tests {
 
         for (src, should_be) in inputs {
             let got = parse_env(src);
-            let should_be = should_be.map(|s| s.to_string());
+            let should_be = should_be.map(ToString::to_string);
 
             assert_eq!(got, should_be);
         }
@@ -752,10 +829,14 @@ mod tests {
 
         cfg.update_from_env();
 
-        assert_eq!(cfg.get_deserialized::<String, _>(key).unwrap(), value);
+        assert_eq!(
+            cfg.get_deserialized_opt::<String, _>(key).unwrap().unwrap(),
+            value
+        );
     }
 
     #[test]
+    #[allow(clippy::approx_constant)]
     fn update_config_using_env_var_and_complex_value() {
         let mut cfg = Config::default();
         let key = "foo-bar.baz";
@@ -770,7 +851,9 @@ mod tests {
         cfg.update_from_env();
 
         assert_eq!(
-            cfg.get_deserialized::<serde_json::Value, _>(key).unwrap(),
+            cfg.get_deserialized_opt::<serde_json::Value, _>(key)
+                .unwrap()
+                .unwrap(),
             value
         );
     }

src/lib.rs

@@ -81,64 +81,57 @@
 //! [`Config`]: config/struct.Config.html
 
 #![deny(missing_docs)]
+#![deny(rust_2018_idioms)]
 
 #[macro_use]
 extern crate error_chain;
-extern crate handlebars;
-extern crate itertools;
 #[macro_use]
 extern crate lazy_static;
 #[macro_use]
 extern crate log;
-extern crate memchr;
-extern crate pulldown_cmark;
-extern crate regex;
-extern crate serde;
 #[macro_use]
 extern crate serde_derive;
 #[macro_use]
 extern crate serde_json;
-extern crate shlex;
-extern crate tempfile;
-extern crate toml;
-extern crate toml_query;
 
 #[cfg(test)]
 #[macro_use]
 extern crate pretty_assertions;
 
-pub mod preprocess;
 pub mod book;
 pub mod config;
+pub mod preprocess;
 pub mod renderer;
 pub mod theme;
 pub mod utils;
 
-pub use book::MDBook;
-pub use book::BookItem;
-pub use renderer::Renderer;
-pub use config::Config;
+/// The current version of `mdbook`.
+///
+/// This is provided as a way for custom preprocessors and renderers to do
+/// compatibility checks.
+pub const MDBOOK_VERSION: &str = env!("CARGO_PKG_VERSION");
+
+pub use crate::book::BookItem;
+pub use crate::book::MDBook;
+pub use crate::config::Config;
+pub use crate::renderer::Renderer;
 
 /// The error types used through out this crate.
 pub mod errors {
     use std::path::PathBuf;
 
-    error_chain!{
+    error_chain! {
         foreign_links {
-            Io(::std::io::Error) #[doc = "A wrapper around `std::io::Error`"];
-            HandlebarsRender(::handlebars::RenderError) #[doc = "Handlebars rendering failed"];
-            HandlebarsTemplate(Box<::handlebars::TemplateError>) #[doc = "Unable to parse the template"];
-            Utf8(::std::string::FromUtf8Error) #[doc = "Invalid UTF-8"];
-            SerdeJson(::serde_json::Error) #[doc = "JSON conversion failed"];
-        }
-
-        links {
-            TomlQuery(::toml_query::error::Error, ::toml_query::error::ErrorKind) #[doc = "A TomlQuery error"];
+            Io(std::io::Error) #[doc = "A wrapper around `std::io::Error`"];
+            HandlebarsRender(handlebars::RenderError) #[doc = "Handlebars rendering failed"];
+            HandlebarsTemplate(Box<handlebars::TemplateError>) #[doc = "Unable to parse the template"];
+            Utf8(std::string::FromUtf8Error) #[doc = "Invalid UTF-8"];
+            SerdeJson(serde_json::Error) #[doc = "JSON conversion failed"];
         }
 
         errors {
             /// A subprocess exited with an unsuccessful return code.
-            Subprocess(message: String, output: ::std::process::Output) {
+            Subprocess(message: String, output: std::process::Output) {
                 description("A subprocess failed")
                 display("{}: {}", message, String::from_utf8_lossy(&output.stdout))
             }
@@ -154,12 +147,18 @@ pub mod errors {
                 description("Reserved Filename")
                 display("{} is reserved for internal use", filename.display())
             }
+
+            /// Error with a TOML file.
+            TomlQueryError(inner: toml_query::error::Error) {
+                description("toml_query error")
+                display("{}", inner)
+            }
         }
     }
 
     // Box to halve the size of Error
-    impl From<::handlebars::TemplateError> for Error {
-        fn from(e: ::handlebars::TemplateError) -> Error {
+    impl From<handlebars::TemplateError> for Error {
+        fn from(e: handlebars::TemplateError) -> Error {
             From::from(Box::new(e))
         }
     }

src/main.rs

@@ -1,75 +1,64 @@
-extern crate chrono;
 #[macro_use]
 extern crate clap;
-extern crate env_logger;
-extern crate error_chain;
 #[macro_use]
 extern crate log;
-extern crate mdbook;
-extern crate open;
 
+use chrono::Local;
+use clap::{App, AppSettings, ArgMatches};
+use env_logger::Builder;
+use log::LevelFilter;
+use mdbook::utils;
 use std::env;
 use std::ffi::OsStr;
-use std::path::{Path, PathBuf};
 use std::io::Write;
-use clap::{App, AppSettings, ArgMatches};
-use chrono::Local;
-use log::LevelFilter;
-use env_logger::Builder;
-use mdbook::utils;
+use std::path::{Path, PathBuf};
 
-pub mod build;
-pub mod clean;
-pub mod init;
-pub mod test;
-#[cfg(feature = "serve")]
-pub mod serve;
-#[cfg(feature = "watch")]
-pub mod watch;
+mod cmd;
 
-const NAME: &'static str = "mdbook";
+const VERSION: &str = concat!("v", crate_version!());
 
 fn main() {
     init_logger();
 
     // Create a list of valid arguments and sub-commands
-    let app = App::new(NAME)
-                .about("Create a book in form of a static website from markdown files")
-                .author("Mathieu David <mathieudavid@mathieudavid.org>")
-                // Get the version from our Cargo.toml using clap's crate_version!() macro
-                .version(concat!("v",crate_version!()))
-                .setting(AppSettings::ArgRequiredElseHelp)
-                .after_help("For more information about a specific command, \
-                             try `mdbook <command> --help`\n\
-                             Source code for mdbook available \
-                             at: https://github.com/rust-lang-nursery/mdBook")
-                .subcommand(init::make_subcommand())
-                .subcommand(build::make_subcommand())
-                .subcommand(test::make_subcommand())
-                .subcommand(clean::make_subcommand());
+    let app = App::new(crate_name!())
+        .about(crate_description!())
+        .author("Mathieu David <mathieudavid@mathieudavid.org>")
+        .version(VERSION)
+        .setting(AppSettings::GlobalVersion)
+        .setting(AppSettings::ArgRequiredElseHelp)
+        .setting(AppSettings::ColoredHelp)
+        .after_help(
+            "For more information about a specific command, try `mdbook <command> --help`\n\
+             The source code for mdBook is available at: https://github.com/rust-lang-nursery/mdBook",
+        )
+        .subcommand(cmd::init::make_subcommand())
+        .subcommand(cmd::build::make_subcommand())
+        .subcommand(cmd::test::make_subcommand())
+        .subcommand(cmd::clean::make_subcommand());
 
     #[cfg(feature = "watch")]
-    let app = app.subcommand(watch::make_subcommand());
+    let app = app.subcommand(cmd::watch::make_subcommand());
     #[cfg(feature = "serve")]
-    let app = app.subcommand(serve::make_subcommand());
+    let app = app.subcommand(cmd::serve::make_subcommand());
 
     // Check which subcomamnd the user ran...
     let res = match app.get_matches().subcommand() {
-        ("init", Some(sub_matches)) => init::execute(sub_matches),
-        ("build", Some(sub_matches)) => build::execute(sub_matches),
-        ("clean", Some(sub_matches)) => clean::execute(sub_matches),
+        ("init", Some(sub_matches)) => cmd::init::execute(sub_matches),
+        ("build", Some(sub_matches)) => cmd::build::execute(sub_matches),
+        ("clean", Some(sub_matches)) => cmd::clean::execute(sub_matches),
         #[cfg(feature = "watch")]
-        ("watch", Some(sub_matches)) => watch::execute(sub_matches),
+        ("watch", Some(sub_matches)) => cmd::watch::execute(sub_matches),
         #[cfg(feature = "serve")]
-        ("serve", Some(sub_matches)) => serve::execute(sub_matches),
-        ("test", Some(sub_matches)) => test::execute(sub_matches),
+        ("serve", Some(sub_matches)) => cmd::serve::execute(sub_matches),
+        ("test", Some(sub_matches)) => cmd::test::execute(sub_matches),
         (_, _) => unreachable!(),
     };
 
     if let Err(e) = res {
         utils::log_backtrace(&e);
 
-        ::std::process::exit(101);
+        std::process::exit(101);
     }
 }
 
@@ -88,7 +77,7 @@ fn init_logger() {
     });
 
     if let Ok(var) = env::var("RUST_LOG") {
-        builder.parse(&var);
+        builder.parse_filters(&var);
     } else {
         // if no RUST_LOG provided, default to logging at the Info level
         builder.filter(None, LevelFilter::Info);

src/preprocess/cmd.rs

@@ -0,0 +1,196 @@
+use super::{Preprocessor, PreprocessorContext};
+use crate::book::Book;
+use crate::errors::*;
+use shlex::Shlex;
+use std::io::{self, Read, Write};
+use std::process::{Child, Command, Stdio};
+
+/// A custom preprocessor which will shell out to a 3rd-party program.
+///
+/// # Preprocessing Protocol
+///
+/// When the `supports_renderer()` method is executed, `CmdPreprocessor` will
+/// execute the shell command `$cmd supports $renderer`. If the renderer is
+/// supported, custom preprocessors should exit with a exit code of `0`,
+/// any other exit code be considered as unsupported.
+///
+/// The `run()` method is implemented by passing a `(PreprocessorContext, Book)`
+/// tuple to the spawned command (`$cmd`) as JSON via `stdin`. Preprocessors
+/// should then "return" a processed book by printing it to `stdout` as JSON.
+/// For convenience, the `CmdPreprocessor::parse_input()` function can be used
+/// to parse the input provided by `mdbook`.
+///
+/// Exiting with a non-zero exit code while preprocessing is considered an
+/// error. `stderr` is passed directly through to the user, so it can be used
+/// for logging or emitting warnings if desired.
+///
+/// # Examples
+///
+/// An example preprocessor is available in this project's `examples/`
+/// directory.
+#[derive(Debug, Clone, PartialEq)]
+pub struct CmdPreprocessor {
+    name: String,
+    cmd: String,
+}
+
+impl CmdPreprocessor {
+    /// Create a new `CmdPreprocessor`.
+    pub fn new(name: String, cmd: String) -> CmdPreprocessor {
+        CmdPreprocessor { name, cmd }
+    }
+
+    /// A convenience function custom preprocessors can use to parse the input
+    /// written to `stdin` by a `CmdRenderer`.
+    pub fn parse_input<R: Read>(reader: R) -> Result<(PreprocessorContext, Book)> {
+        serde_json::from_reader(reader).chain_err(|| "Unable to parse the input")
+    }
+
+    fn write_input_to_child(&self, child: &mut Child, book: &Book, ctx: &PreprocessorContext) {
+        let stdin = child.stdin.take().expect("Child has stdin");
+
+        if let Err(e) = self.write_input(stdin, &book, &ctx) {
+            // Looks like the backend hung up before we could finish
+            // sending it the render context. Log the error and keep going
+            warn!("Error writing the RenderContext to the backend, {}", e);
+        }
+    }
+
+    fn write_input<W: Write>(
+        &self,
+        writer: W,
+        book: &Book,
+        ctx: &PreprocessorContext,
+    ) -> Result<()> {
+        serde_json::to_writer(writer, &(ctx, book)).map_err(Into::into)
+    }
+
+    /// The command this `Preprocessor` will invoke.
+    pub fn cmd(&self) -> &str {
+        &self.cmd
+    }
+
+    fn command(&self) -> Result<Command> {
+        let mut words = Shlex::new(&self.cmd);
+        let executable = match words.next() {
+            Some(e) => e,
+            None => bail!("Command string was empty"),
+        };
+
+        let mut cmd = Command::new(executable);
+
+        for arg in words {
+            cmd.arg(arg);
+        }
+
+        Ok(cmd)
+    }
+}
+
+impl Preprocessor for CmdPreprocessor {
+    fn name(&self) -> &str {
+        &self.name
+    }
+
+    fn run(&self, ctx: &PreprocessorContext, book: Book) -> Result<Book> {
+        let mut cmd = self.command()?;
+
+        let mut child = cmd
+            .stdin(Stdio::piped())
+            .stdout(Stdio::piped())
+            .stderr(Stdio::inherit())
+            .spawn()
+            .chain_err(|| {
+                format!(
+                    "Unable to start the \"{}\" preprocessor. Is it installed?",
+                    self.name()
+                )
+            })?;
+
+        self.write_input_to_child(&mut child, &book, ctx);
+
+        let output = child
+            .wait_with_output()
+            .chain_err(|| "Error waiting for the preprocessor to complete")?;
+
+        trace!("{} exited with output: {:?}", self.cmd, output);
+        ensure!(
+            output.status.success(),
+            "The preprocessor exited unsuccessfully"
+        );
+
+        serde_json::from_slice(&output.stdout).chain_err(|| "Unable to parse the preprocessed book")
+    }
+
+    fn supports_renderer(&self, renderer: &str) -> bool {
+        debug!(
+            "Checking if the \"{}\" preprocessor supports \"{}\"",
+            self.name(),
+            renderer
+        );
+
+        let mut cmd = match self.command() {
+            Ok(c) => c,
+            Err(e) => {
+                warn!(
+                    "Unable to create the command for the \"{}\" preprocessor, {}",
+                    self.name(),
+                    e
+                );
+                return false;
+            }
+        };
+
+        let outcome = cmd
+            .arg("supports")
+            .arg(renderer)
+            .stdin(Stdio::null())
+            .stdout(Stdio::inherit())
+            .stderr(Stdio::inherit())
+            .status()
+            .map(|status| status.code() == Some(0));
+
+        if let Err(ref e) = outcome {
+            if e.kind() == io::ErrorKind::NotFound {
+                warn!(
+                    "The command wasn't found, is the \"{}\" preprocessor installed?",
+                    self.name
+                );
+                warn!("\tCommand: {}", self.cmd);
+            }
+        }
+
+        outcome.unwrap_or(false)
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use crate::MDBook;
+    use std::path::Path;
+
+    fn book_example() -> MDBook {
+        let example = Path::new(env!("CARGO_MANIFEST_DIR")).join("book-example");
+        MDBook::load(example).unwrap()
+    }
+
+    #[test]
+    fn round_trip_write_and_parse_input() {
+        let cmd = CmdPreprocessor::new("test".to_string(), "test".to_string());
+        let md = book_example();
+        let ctx = PreprocessorContext::new(
+            md.root.clone(),
+            md.config.clone(),
+            "some-renderer".to_string(),
+        );
+
+        let mut buffer = Vec::new();
+        cmd.write_input(&mut buffer, &md.book, &ctx).unwrap();
+
+        let (got_ctx, got_book) = CmdPreprocessor::parse_input(buffer.as_slice()).unwrap();
+
+        assert_eq!(got_book, md.book);
+        assert_eq!(got_ctx, ctx);
+    }
+}

src/preprocess/index.rs

@@ -1,16 +1,19 @@
-use std::path::Path;
 use regex::Regex;
+use std::path::Path;
 
-use errors::*;
+use crate::errors::*;
 
 use super::{Preprocessor, PreprocessorContext};
-use book::{Book, BookItem};
+use crate::book::{Book, BookItem};
 
 /// A preprocessor for converting file name `README.md` to `index.md` since
-/// `README.md` is the de facto index file in a markdown-based documentation.
+/// `README.md` is the de facto index file in markdown-based documentation.
+#[derive(Default)]
 pub struct IndexPreprocessor;
 
 impl IndexPreprocessor {
+    pub(crate) const NAME: &'static str = "index";
+
     /// Create a new `IndexPreprocessor`.
     pub fn new() -> Self {
         IndexPreprocessor
@@ -19,16 +22,15 @@ impl IndexPreprocessor {
 
 impl Preprocessor for IndexPreprocessor {
     fn name(&self) -> &str {
-        "index"
+        Self::NAME
     }
 
-    fn run(&self, ctx: &PreprocessorContext, book: &mut Book) -> Result<()> {
+    fn run(&self, ctx: &PreprocessorContext, mut book: Book) -> Result<Book> {
         let source_dir = ctx.root.join(&ctx.config.book.src);
         book.for_each_mut(|section: &mut BookItem| {
             if let BookItem::Chapter(ref mut ch) = *section {
                 if is_readme_file(&ch.path) {
-                    let index_md = source_dir
-                        .join(ch.path.with_file_name("index.md"));
+                    let index_md = source_dir.join(ch.path.with_file_name("index.md"));
                     if index_md.exists() {
                         warn_readme_name_conflict(&ch.path, &index_md);
                     }
@@ -38,15 +40,25 @@ impl Preprocessor for IndexPreprocessor {
             }
         });
 
-        Ok(())
+        Ok(book)
     }
 }
 
 fn warn_readme_name_conflict<P: AsRef<Path>>(readme_path: P, index_path: P) {
     let file_name = readme_path.as_ref().file_name().unwrap_or_default();
-    let parent_dir = index_path.as_ref().parent().unwrap_or(index_path.as_ref());
-    warn!("It seems that there are both {:?} and index.md under \"{}\".", file_name, parent_dir.display());
-    warn!("mdbook converts {:?} into index.html by default. It may cause", file_name);
+    let parent_dir = index_path
+        .as_ref()
+        .parent()
+        .unwrap_or_else(|| index_path.as_ref());
+    warn!(
+        "It seems that there are both {:?} and index.md under \"{}\".",
+        file_name,
+        parent_dir.display()
+    );
+    warn!(
+        "mdbook converts {:?} into index.html by default. It may cause",
+        file_name
+    );
     warn!("unexpected behavior if putting both files under the same directory.");
     warn!("To solve the warning, try to rearrange the book structure or disable");
     warn!("\"index\" preprocessor to stop the conversion.");
@@ -59,8 +71,8 @@ fn is_readme_file<P: AsRef<Path>>(path: P) -> bool {
     RE.is_match(
         path.as_ref()
             .file_stem()
-            .and_then(|s| s.to_str())
-            .unwrap_or_default()
+            .and_then(std::ffi::OsStr::to_str)
+            .unwrap_or_default(),
     )
 }
 

src/preprocess/links.rs

@@ -1,21 +1,34 @@
-use std::ops::{Range, RangeFrom, RangeFull, RangeTo};
-use std::path::{Path, PathBuf};
+use crate::errors::*;
+use crate::utils::{
+    take_anchored_lines, take_lines, take_rustdoc_include_anchored_lines,
+    take_rustdoc_include_lines,
+};
 use regex::{CaptureMatches, Captures, Regex};
-use utils::fs::file_to_string;
-use utils::take_lines;
-use errors::*;
+use std::fs;
+use std::ops::{Bound, Range, RangeBounds, RangeFrom, RangeFull, RangeTo};
+use std::path::{Path, PathBuf};
 
 use super::{Preprocessor, PreprocessorContext};
-use book::{Book, BookItem};
+use crate::book::{Book, BookItem};
 
 const ESCAPE_CHAR: char = '\\';
 const MAX_LINK_NESTED_DEPTH: usize = 10;
 
-/// A preprocessor for expanding the `{{# playpen}}` and `{{# include}}`
-/// helpers in a chapter.
+/// A preprocessor for expanding helpers in a chapter. Supported helpers are:
+///
+/// - `{{# include}}` - Insert an external file of any type. Include the whole file, only particular
+///.  lines, or only between the specified anchors.
+/// - `{{# rustdoc_include}}` - Insert an external Rust file, showing the particular lines
+///.  specified or the lines between specified anchors, and include the rest of the file behind `#`.
+///   This hides the lines from initial display but shows them when the reader expands the code
+///   block and provides them to Rustdoc for testing.
+/// - `{{# playpen}}` - Insert runnable Rust files
+#[derive(Default)]
 pub struct LinkPreprocessor;
 
 impl LinkPreprocessor {
+    pub(crate) const NAME: &'static str = "links";
+
     /// Create a new `LinkPreprocessor`.
     pub fn new() -> Self {
         LinkPreprocessor
@@ -24,15 +37,16 @@ impl LinkPreprocessor {
 
 impl Preprocessor for LinkPreprocessor {
     fn name(&self) -> &str {
-        "links"
+        Self::NAME
     }
 
-    fn run(&self, ctx: &PreprocessorContext, book: &mut Book) -> Result<()> {
+    fn run(&self, ctx: &PreprocessorContext, mut book: Book) -> Result<Book> {
         let src_dir = ctx.root.join(&ctx.config.book.src);
 
         book.for_each_mut(|section: &mut BookItem| {
             if let BookItem::Chapter(ref mut ch) = *section {
-                let base = ch.path
+                let base = ch
+                    .path
                     .parent()
                     .map(|dir| src_dir.join(dir))
                     .expect("All book items have a parent");
@@ -42,11 +56,15 @@ impl Preprocessor for LinkPreprocessor {
             }
         });
 
-        Ok(())
+        Ok(book)
     }
 }
 
-fn replace_all<P: AsRef<Path>>(s: &str, path: P, source: &P, depth: usize) -> String {
+fn replace_all<P1, P2>(s: &str, path: P1, source: P2, depth: usize) -> String
+where
+    P1: AsRef<Path>,
+    P2: AsRef<Path>,
+{
     // When replacing one thing in a string by something with a different length,
     // the indices after that will not correspond,
     // we therefore have to store the difference to correct this
@@ -55,27 +73,34 @@ fn replace_all<P: AsRef<Path>>(s: &str, path: P, source: &P, depth: usize) -> St
     let mut previous_end_index = 0;
     let mut replaced = String::new();
 
-    for playpen in find_links(s) {
-        replaced.push_str(&s[previous_end_index..playpen.start_index]);
+    for link in find_links(s) {
+        replaced.push_str(&s[previous_end_index..link.start_index]);
 
-        match playpen.render_with_path(&path) {
+        match link.render_with_path(&path) {
             Ok(new_content) => {
                 if depth < MAX_LINK_NESTED_DEPTH {
-                    if let Some(rel_path) = playpen.link.relative_path(path) {
-                        replaced.push_str(&replace_all(&new_content, rel_path, &source.to_path_buf(), depth + 1));
+                    if let Some(rel_path) = link.link_type.relative_path(path) {
+                        replaced.push_str(&replace_all(&new_content, rel_path, source, depth + 1));
+                    } else {
+                        replaced.push_str(&new_content);
                     }
+                } else {
+                    error!(
+                        "Stack depth exceeded in {}. Check for cyclic includes",
+                        source.display()
+                    );
                 }
-                else {
-                    error!("Stack depth exceeded in {}. Check for cyclic includes",
-                            source.display());
-                }
-                previous_end_index = playpen.end_index;
+                previous_end_index = link.end_index;
             }
             Err(e) => {
-                error!("Error updating \"{}\", {}", playpen.link_text, e);
+                error!("Error updating \"{}\", {}", link.link_text, e);
+                for cause in e.iter().skip(1) {
+                    warn!("Caused By: {}", cause);
+                }
+
                 // This should make sure we include the raw `{{# ... }}` snippet
                 // in the page content if there are any errors.
-                previous_end_index = playpen.start_index;
+                previous_end_index = link.start_index;
             }
         }
     }
@@ -87,11 +112,68 @@ fn replace_all<P: AsRef<Path>>(s: &str, path: P, source: &P, depth: usize) -> St
 #[derive(PartialEq, Debug, Clone)]
 enum LinkType<'a> {
     Escaped,
-    IncludeRange(PathBuf, Range<usize>),
-    IncludeRangeFrom(PathBuf, RangeFrom<usize>),
-    IncludeRangeTo(PathBuf, RangeTo<usize>),
-    IncludeRangeFull(PathBuf, RangeFull),
+    Include(PathBuf, RangeOrAnchor),
     Playpen(PathBuf, Vec<&'a str>),
+    RustdocInclude(PathBuf, RangeOrAnchor),
+}
+
+#[derive(PartialEq, Debug, Clone)]
+enum RangeOrAnchor {
+    Range(LineRange),
+    Anchor(String),
+}
+
+// A range of lines specified with some include directive.
+#[derive(PartialEq, Debug, Clone)]
+enum LineRange {
+    Range(Range<usize>),
+    RangeFrom(RangeFrom<usize>),
+    RangeTo(RangeTo<usize>),
+    RangeFull(RangeFull),
+}
+
+impl RangeBounds<usize> for LineRange {
+    fn start_bound(&self) -> Bound<&usize> {
+        match self {
+            LineRange::Range(r) => r.start_bound(),
+            LineRange::RangeFrom(r) => r.start_bound(),
+            LineRange::RangeTo(r) => r.start_bound(),
+            LineRange::RangeFull(r) => r.start_bound(),
+        }
+    }
+
+    fn end_bound(&self) -> Bound<&usize> {
+        match self {
+            LineRange::Range(r) => r.end_bound(),
+            LineRange::RangeFrom(r) => r.end_bound(),
+            LineRange::RangeTo(r) => r.end_bound(),
+            LineRange::RangeFull(r) => r.end_bound(),
+        }
+    }
+}
+
+impl From<Range<usize>> for LineRange {
+    fn from(r: Range<usize>) -> LineRange {
+        LineRange::Range(r)
+    }
+}
+
+impl From<RangeFrom<usize>> for LineRange {
+    fn from(r: RangeFrom<usize>) -> LineRange {
+        LineRange::RangeFrom(r)
+    }
+}
+
+impl From<RangeTo<usize>> for LineRange {
+    fn from(r: RangeTo<usize>) -> LineRange {
+        LineRange::RangeTo(r)
+    }
+}
+
+impl From<RangeFull> for LineRange {
+    fn from(r: RangeFull) -> LineRange {
+        LineRange::RangeFull(r)
+    }
 }
 
 impl<'a> LinkType<'a> {
@@ -99,11 +181,9 @@ impl<'a> LinkType<'a> {
         let base = base.as_ref();
         match self {
             LinkType::Escaped => None,
-            LinkType::IncludeRange(p, _) => Some(return_relative_path(base, &p)),
-            LinkType::IncludeRangeFrom(p, _) => Some(return_relative_path(base, &p)),
-            LinkType::IncludeRangeTo(p, _) => Some(return_relative_path(base, &p)),
-            LinkType::IncludeRangeFull(p, _) => Some(return_relative_path(base, &p)),
-            LinkType::Playpen(p,_) => Some(return_relative_path(base, &p))
+            LinkType::Include(p, _) => Some(return_relative_path(base, &p)),
+            LinkType::Playpen(p, _) => Some(return_relative_path(base, &p)),
+            LinkType::RustdocInclude(p, _) => Some(return_relative_path(base, &p)),
         }
     }
 }
@@ -115,50 +195,59 @@ fn return_relative_path<P: AsRef<Path>>(base: P, relative: P) -> PathBuf {
         .to_path_buf()
 }
 
-fn parse_include_path(path: &str) -> LinkType<'static> {
-    let mut parts = path.split(':');
-    let path = parts.next().unwrap().into();
-    // subtract 1 since line numbers usually begin with 1
-    let start = parts
-        .next()
-        .and_then(|s| s.parse::<usize>().ok())
-        .map(|val| val.saturating_sub(1));
+fn parse_range_or_anchor(parts: Option<&str>) -> RangeOrAnchor {
+    let mut parts = parts.unwrap_or("").splitn(3, ':').fuse();
+
+    let next_element = parts.next();
+    let start = if let Some(value) = next_element.and_then(|s| s.parse::<usize>().ok()) {
+        // subtract 1 since line numbers usually begin with 1
+        Some(value.saturating_sub(1))
+    } else if let Some("") = next_element {
+        None
+    } else if let Some(anchor) = next_element {
+        return RangeOrAnchor::Anchor(String::from(anchor));
+    } else {
+        None
+    };
+
     let end = parts.next();
-    let has_end = end.is_some();
-    let end = end.and_then(|s| s.parse::<usize>().ok());
-    match start {
-        Some(start) => match end {
-            Some(end) => LinkType::IncludeRange(
-                path,
-                Range {
-                    start: start,
-                    end: end,
-                },
-            ),
-            None => if has_end {
-                LinkType::IncludeRangeFrom(path, RangeFrom { start: start })
-            } else {
-                LinkType::IncludeRange(
-                    path,
-                    Range {
-                        start: start,
-                        end: start + 1,
-                    },
-                )
-            },
-        },
-        None => match end {
-            Some(end) => LinkType::IncludeRangeTo(path, RangeTo { end: end }),
-            None => LinkType::IncludeRangeFull(path, RangeFull),
-        },
+    // If `end` is empty string or any other value that can't be parsed as a usize, treat this
+    // include as a range with only a start bound. However, if end isn't specified, include only
+    // the single line specified by `start`.
+    let end = end.map(|s| s.parse::<usize>());
+
+    match (start, end) {
+        (Some(start), Some(Ok(end))) => RangeOrAnchor::Range(LineRange::from(start..end)),
+        (Some(start), Some(Err(_))) => RangeOrAnchor::Range(LineRange::from(start..)),
+        (Some(start), None) => RangeOrAnchor::Range(LineRange::from(start..start + 1)),
+        (None, Some(Ok(end))) => RangeOrAnchor::Range(LineRange::from(..end)),
+        (None, None) | (None, Some(Err(_))) => RangeOrAnchor::Range(LineRange::from(RangeFull)),
     }
 }
 
+fn parse_include_path(path: &str) -> LinkType<'static> {
+    let mut parts = path.splitn(2, ':');
+
+    let path = parts.next().unwrap().into();
+    let range_or_anchor = parse_range_or_anchor(parts.next());
+
+    LinkType::Include(path, range_or_anchor)
+}
+
+fn parse_rustdoc_include_path(path: &str) -> LinkType<'static> {
+    let mut parts = path.splitn(2, ':');
+
+    let path = parts.next().unwrap().into();
+    let range_or_anchor = parse_range_or_anchor(parts.next());
+
+    LinkType::RustdocInclude(path, range_or_anchor)
+}
+
 #[derive(PartialEq, Debug, Clone)]
 struct Link<'a> {
     start_index: usize,
     end_index: usize,
-    link: LinkType<'a>,
+    link_type: LinkType<'a>,
     link_text: &'a str,
 }
 
@@ -173,6 +262,7 @@ impl<'a> Link<'a> {
                 match (typ.as_str(), file_arg) {
                     ("include", Some(pth)) => Some(parse_include_path(pth)),
                     ("playpen", Some(pth)) => Some(LinkType::Playpen(pth.into(), props)),
+                    ("rustdoc_include", Some(pth)) => Some(parse_rustdoc_include_path(pth)),
                     _ => None,
                 }
             }
@@ -182,11 +272,11 @@ impl<'a> Link<'a> {
             _ => None,
         };
 
-        link_type.and_then(|lnk| {
+        link_type.and_then(|lnk_type| {
             cap.get(0).map(|mat| Link {
                 start_index: mat.start(),
                 end_index: mat.end(),
-                link: lnk,
+                link_type: lnk_type,
                 link_text: mat.as_str(),
             })
         })
@@ -194,23 +284,55 @@ impl<'a> Link<'a> {
 
     fn render_with_path<P: AsRef<Path>>(&self, base: P) -> Result<String> {
         let base = base.as_ref();
-        match self.link {
+        match self.link_type {
             // omit the escape char
             LinkType::Escaped => Ok((&self.link_text[1..]).to_owned()),
-            LinkType::IncludeRange(ref pat, ref range) => file_to_string(base.join(pat))
-                .map(|s| take_lines(&s, range.clone()))
-                .chain_err(|| format!("Could not read file for link {}", self.link_text)),
-            LinkType::IncludeRangeFrom(ref pat, ref range) => file_to_string(base.join(pat))
-                .map(|s| take_lines(&s, range.clone()))
-                .chain_err(|| format!("Could not read file for link {}", self.link_text)),
-            LinkType::IncludeRangeTo(ref pat, ref range) => file_to_string(base.join(pat))
-                .map(|s| take_lines(&s, range.clone()))
-                .chain_err(|| format!("Could not read file for link {}", self.link_text)),
-            LinkType::IncludeRangeFull(ref pat, _) => file_to_string(base.join(pat))
-                .chain_err(|| format!("Could not read file for link {}", self.link_text)),
+            LinkType::Include(ref pat, ref range_or_anchor) => {
+                let target = base.join(pat);
+
+                fs::read_to_string(&target)
+                    .map(|s| match range_or_anchor {
+                        RangeOrAnchor::Range(range) => take_lines(&s, range.clone()),
+                        RangeOrAnchor::Anchor(anchor) => take_anchored_lines(&s, anchor),
+                    })
+                    .chain_err(|| {
+                        format!(
+                            "Could not read file for link {} ({})",
+                            self.link_text,
+                            target.display(),
+                        )
+                    })
+            }
+            LinkType::RustdocInclude(ref pat, ref range_or_anchor) => {
+                let target = base.join(pat);
+
+                fs::read_to_string(&target)
+                    .map(|s| match range_or_anchor {
+                        RangeOrAnchor::Range(range) => {
+                            take_rustdoc_include_lines(&s, range.clone())
+                        }
+                        RangeOrAnchor::Anchor(anchor) => {
+                            take_rustdoc_include_anchored_lines(&s, anchor)
+                        }
+                    })
+                    .chain_err(|| {
+                        format!(
+                            "Could not read file for link {} ({})",
+                            self.link_text,
+                            target.display(),
+                        )
+                    })
+            }
             LinkType::Playpen(ref pat, ref attrs) => {
-                let contents = file_to_string(base.join(pat))
-                    .chain_err(|| format!("Could not read file for link {}", self.link_text))?;
+                let target = base.join(pat);
+
+                let contents = fs::read_to_string(&target).chain_err(|| {
+                    format!(
+                        "Could not read file for link {} ({})",
+                        self.link_text,
+                        target.display()
+                    )
+                })?;
                 let ftype = if !attrs.is_empty() { "rust," } else { "rust" };
                 Ok(format!(
                     "```{}{}\n{}\n```\n",
@@ -237,19 +359,21 @@ impl<'a> Iterator for LinkIter<'a> {
     }
 }
 
-fn find_links(contents: &str) -> LinkIter {
+fn find_links(contents: &str) -> LinkIter<'_> {
     // lazily compute following regex
     // r"\\\{\{#.*\}\}|\{\{#([a-zA-Z0-9]+)\s*([a-zA-Z0-9_.\-:/\\\s]+)\}\}")?;
     lazy_static! {
-        static ref RE: Regex = Regex::new(r"(?x) # insignificant whitespace mode
-                    \\\{\{\#.*\}\}               # match escaped link
-                    |                            # or
-                    \{\{\s*                      # link opening parens and whitespace
-                      \#([a-zA-Z0-9]+)           # link type
-                      \s+                        # separating whitespace
-                      ([a-zA-Z0-9\s_.\-:/\\]+)   # link target path and space separated properties
-                    \s*\}\}                      # whitespace and link closing parens
-                                 ").unwrap();
+        static ref RE: Regex = Regex::new(
+            r"(?x)                     # insignificant whitespace mode
+            \\\{\{\#.*\}\}             # match escaped link
+            |                          # or
+            \{\{\s*                    # link opening parens and whitespace
+            \#([a-zA-Z0-9_]+)          # link type
+            \s+                        # separating whitespace
+            ([a-zA-Z0-9\s_.\-:/\\]+)   # link target path and space separated properties
+            \s*\}\}                    # whitespace and link closing parens"
+        )
+        .unwrap();
     }
     LinkIter(RE.captures_iter(contents))
 }
@@ -258,6 +382,21 @@ fn find_links(contents: &str) -> LinkIter {
 mod tests {
     use super::*;
 
+    #[test]
+    fn test_replace_all_escaped() {
+        let start = r"
+        Some text over here.
+        ```hbs
+        \{{#include file.rs}} << an escaped link!
+        ```";
+        let end = r"
+        Some text over here.
+        ```hbs
+        {{#include file.rs}} << an escaped link!
+        ```";
+        assert_eq!(replace_all(start, "", "", 0), end);
+    }
+
     #[test]
     fn test_find_links_no_link() {
         let s = "Some random text without link...";
@@ -299,13 +438,13 @@ mod tests {
                 Link {
                     start_index: 22,
                     end_index: 42,
-                    link: LinkType::Playpen(PathBuf::from("file.rs"), vec![]),
+                    link_type: LinkType::Playpen(PathBuf::from("file.rs"), vec![]),
                     link_text: "{{#playpen file.rs}}",
                 },
                 Link {
                     start_index: 47,
                     end_index: 68,
-                    link: LinkType::Playpen(PathBuf::from("test.rs"), vec![]),
+                    link_type: LinkType::Playpen(PathBuf::from("test.rs"), vec![]),
                     link_text: "{{#playpen test.rs }}",
                 },
             ]
@@ -319,14 +458,15 @@ mod tests {
         println!("\nOUTPUT: {:?}\n", res);
         assert_eq!(
             res,
-            vec![
-                Link {
-                    start_index: 22,
-                    end_index: 48,
-                    link: LinkType::IncludeRange(PathBuf::from("file.rs"), 9..20),
-                    link_text: "{{#include file.rs:10:20}}",
-                },
-            ]
+            vec![Link {
+                start_index: 22,
+                end_index: 48,
+                link_type: LinkType::Include(
+                    PathBuf::from("file.rs"),
+                    RangeOrAnchor::Range(LineRange::from(9..20))
+                ),
+                link_text: "{{#include file.rs:10:20}}",
+            }]
         );
     }
 
@@ -337,14 +477,15 @@ mod tests {
         println!("\nOUTPUT: {:?}\n", res);
         assert_eq!(
             res,
-            vec![
-                Link {
-                    start_index: 22,
-                    end_index: 45,
-                    link: LinkType::IncludeRange(PathBuf::from("file.rs"), 9..10),
-                    link_text: "{{#include file.rs:10}}",
-                },
-            ]
+            vec![Link {
+                start_index: 22,
+                end_index: 45,
+                link_type: LinkType::Include(
+                    PathBuf::from("file.rs"),
+                    RangeOrAnchor::Range(LineRange::from(9..10))
+                ),
+                link_text: "{{#include file.rs:10}}",
+            }]
         );
     }
 
@@ -355,14 +496,15 @@ mod tests {
         println!("\nOUTPUT: {:?}\n", res);
         assert_eq!(
             res,
-            vec![
-                Link {
-                    start_index: 22,
-                    end_index: 46,
-                    link: LinkType::IncludeRangeFrom(PathBuf::from("file.rs"), 9..),
-                    link_text: "{{#include file.rs:10:}}",
-                },
-            ]
+            vec![Link {
+                start_index: 22,
+                end_index: 46,
+                link_type: LinkType::Include(
+                    PathBuf::from("file.rs"),
+                    RangeOrAnchor::Range(LineRange::from(9..))
+                ),
+                link_text: "{{#include file.rs:10:}}",
+            }]
         );
     }
 
@@ -373,14 +515,15 @@ mod tests {
         println!("\nOUTPUT: {:?}\n", res);
         assert_eq!(
             res,
-            vec![
-                Link {
-                    start_index: 22,
-                    end_index: 46,
-                    link: LinkType::IncludeRangeTo(PathBuf::from("file.rs"), ..20),
-                    link_text: "{{#include file.rs::20}}",
-                },
-            ]
+            vec![Link {
+                start_index: 22,
+                end_index: 46,
+                link_type: LinkType::Include(
+                    PathBuf::from("file.rs"),
+                    RangeOrAnchor::Range(LineRange::from(..20))
+                ),
+                link_text: "{{#include file.rs::20}}",
+            }]
         );
     }
 
@@ -391,14 +534,15 @@ mod tests {
         println!("\nOUTPUT: {:?}\n", res);
         assert_eq!(
             res,
-            vec![
-                Link {
-                    start_index: 22,
-                    end_index: 44,
-                    link: LinkType::IncludeRangeFull(PathBuf::from("file.rs"), ..),
-                    link_text: "{{#include file.rs::}}",
-                },
-            ]
+            vec![Link {
+                start_index: 22,
+                end_index: 44,
+                link_type: LinkType::Include(
+                    PathBuf::from("file.rs"),
+                    RangeOrAnchor::Range(LineRange::from(..))
+                ),
+                link_text: "{{#include file.rs::}}",
+            }]
         );
     }
 
@@ -409,14 +553,34 @@ mod tests {
         println!("\nOUTPUT: {:?}\n", res);
         assert_eq!(
             res,
-            vec![
-                Link {
-                    start_index: 22,
-                    end_index: 42,
-                    link: LinkType::IncludeRangeFull(PathBuf::from("file.rs"), ..),
-                    link_text: "{{#include file.rs}}",
-                },
-            ]
+            vec![Link {
+                start_index: 22,
+                end_index: 42,
+                link_type: LinkType::Include(
+                    PathBuf::from("file.rs"),
+                    RangeOrAnchor::Range(LineRange::from(..))
+                ),
+                link_text: "{{#include file.rs}}",
+            }]
+        );
+    }
+
+    #[test]
+    fn test_find_links_with_anchor() {
+        let s = "Some random text with {{#include file.rs:anchor}}...";
+        let res = find_links(s).collect::<Vec<_>>();
+        println!("\nOUTPUT: {:?}\n", res);
+        assert_eq!(
+            res,
+            vec![Link {
+                start_index: 22,
+                end_index: 49,
+                link_type: LinkType::Include(
+                    PathBuf::from("file.rs"),
+                    RangeOrAnchor::Anchor(String::from("anchor"))
+                ),
+                link_text: "{{#include file.rs:anchor}}",
+            }]
         );
     }
 
@@ -429,14 +593,12 @@ mod tests {
 
         assert_eq!(
             res,
-            vec![
-                Link {
-                    start_index: 38,
-                    end_index: 68,
-                    link: LinkType::Escaped,
-                    link_text: "\\{{#playpen file.rs editable}}",
-                },
-            ]
+            vec![Link {
+                start_index: 38,
+                end_index: 68,
+                link_type: LinkType::Escaped,
+                link_text: "\\{{#playpen file.rs editable}}",
+            }]
         );
     }
 
@@ -453,13 +615,13 @@ mod tests {
                 Link {
                     start_index: 38,
                     end_index: 68,
-                    link: LinkType::Playpen(PathBuf::from("file.rs"), vec!["editable"]),
+                    link_type: LinkType::Playpen(PathBuf::from("file.rs"), vec!["editable"]),
                     link_text: "{{#playpen file.rs editable }}",
                 },
                 Link {
                     start_index: 89,
                     end_index: 136,
-                    link: LinkType::Playpen(
+                    link_type: LinkType::Playpen(
                         PathBuf::from("my.rs"),
                         vec!["editable", "no_run", "should_panic"],
                     ),
@@ -483,7 +645,10 @@ mod tests {
             Link {
                 start_index: 38,
                 end_index: 58,
-                link: LinkType::IncludeRangeFull(PathBuf::from("file.rs"), ..),
+                link_type: LinkType::Include(
+                    PathBuf::from("file.rs"),
+                    RangeOrAnchor::Range(LineRange::from(..))
+                ),
                 link_text: "{{#include file.rs}}",
             }
         );
@@ -492,7 +657,7 @@ mod tests {
             Link {
                 start_index: 63,
                 end_index: 112,
-                link: LinkType::Escaped,
+                link_type: LinkType::Escaped,
                 link_text: "\\{{#contents are insignifficant in escaped link}}",
             }
         );
@@ -501,7 +666,7 @@ mod tests {
             Link {
                 start_index: 130,
                 end_index: 177,
-                link: LinkType::Playpen(
+                link_type: LinkType::Playpen(
                     PathBuf::from("my.rs"),
                     vec!["editable", "no_run", "should_panic"]
                 ),
@@ -510,4 +675,183 @@ mod tests {
         );
     }
 
+    #[test]
+    fn parse_without_colon_includes_all() {
+        let link_type = parse_include_path("arbitrary");
+        assert_eq!(
+            link_type,
+            LinkType::Include(
+                PathBuf::from("arbitrary"),
+                RangeOrAnchor::Range(LineRange::from(RangeFull))
+            )
+        );
+    }
+
+    #[test]
+    fn parse_with_nothing_after_colon_includes_all() {
+        let link_type = parse_include_path("arbitrary:");
+        assert_eq!(
+            link_type,
+            LinkType::Include(
+                PathBuf::from("arbitrary"),
+                RangeOrAnchor::Range(LineRange::from(RangeFull))
+            )
+        );
+    }
+
+    #[test]
+    fn parse_with_two_colons_includes_all() {
+        let link_type = parse_include_path("arbitrary::");
+        assert_eq!(
+            link_type,
+            LinkType::Include(
+                PathBuf::from("arbitrary"),
+                RangeOrAnchor::Range(LineRange::from(RangeFull))
+            )
+        );
+    }
+
+    #[test]
+    fn parse_with_garbage_after_two_colons_includes_all() {
+        let link_type = parse_include_path("arbitrary::NaN");
+        assert_eq!(
+            link_type,
+            LinkType::Include(
+                PathBuf::from("arbitrary"),
+                RangeOrAnchor::Range(LineRange::from(RangeFull))
+            )
+        );
+    }
+
+    #[test]
+    fn parse_with_one_number_after_colon_only_that_line() {
+        let link_type = parse_include_path("arbitrary:5");
+        assert_eq!(
+            link_type,
+            LinkType::Include(
+                PathBuf::from("arbitrary"),
+                RangeOrAnchor::Range(LineRange::from(4..5))
+            )
+        );
+    }
+
+    #[test]
+    fn parse_with_one_based_start_becomes_zero_based() {
+        let link_type = parse_include_path("arbitrary:1");
+        assert_eq!(
+            link_type,
+            LinkType::Include(
+                PathBuf::from("arbitrary"),
+                RangeOrAnchor::Range(LineRange::from(0..1))
+            )
+        );
+    }
+
+    #[test]
+    fn parse_with_zero_based_start_stays_zero_based_but_is_probably_an_error() {
+        let link_type = parse_include_path("arbitrary:0");
+        assert_eq!(
+            link_type,
+            LinkType::Include(
+                PathBuf::from("arbitrary"),
+                RangeOrAnchor::Range(LineRange::from(0..1))
+            )
+        );
+    }
+
+    #[test]
+    fn parse_start_only_range() {
+        let link_type = parse_include_path("arbitrary:5:");
+        assert_eq!(
+            link_type,
+            LinkType::Include(
+                PathBuf::from("arbitrary"),
+                RangeOrAnchor::Range(LineRange::from(4..))
+            )
+        );
+    }
+
+    #[test]
+    fn parse_start_with_garbage_interpreted_as_start_only_range() {
+        let link_type = parse_include_path("arbitrary:5:NaN");
+        assert_eq!(
+            link_type,
+            LinkType::Include(
+                PathBuf::from("arbitrary"),
+                RangeOrAnchor::Range(LineRange::from(4..))
+            )
+        );
+    }
+
+    #[test]
+    fn parse_end_only_range() {
+        let link_type = parse_include_path("arbitrary::5");
+        assert_eq!(
+            link_type,
+            LinkType::Include(
+                PathBuf::from("arbitrary"),
+                RangeOrAnchor::Range(LineRange::from(..5))
+            )
+        );
+    }
+
+    #[test]
+    fn parse_start_and_end_range() {
+        let link_type = parse_include_path("arbitrary:5:10");
+        assert_eq!(
+            link_type,
+            LinkType::Include(
+                PathBuf::from("arbitrary"),
+                RangeOrAnchor::Range(LineRange::from(4..10))
+            )
+        );
+    }
+
+    #[test]
+    fn parse_with_negative_interpreted_as_anchor() {
+        let link_type = parse_include_path("arbitrary:-5");
+        assert_eq!(
+            link_type,
+            LinkType::Include(
+                PathBuf::from("arbitrary"),
+                RangeOrAnchor::Anchor("-5".to_string())
+            )
+        );
+    }
+
+    #[test]
+    fn parse_with_floating_point_interpreted_as_anchor() {
+        let link_type = parse_include_path("arbitrary:-5.7");
+        assert_eq!(
+            link_type,
+            LinkType::Include(
+                PathBuf::from("arbitrary"),
+                RangeOrAnchor::Anchor("-5.7".to_string())
+            )
+        );
+    }
+
+    #[test]
+    fn parse_with_anchor_followed_by_colon() {
+        let link_type = parse_include_path("arbitrary:some-anchor:this-gets-ignored");
+        assert_eq!(
+            link_type,
+            LinkType::Include(
+                PathBuf::from("arbitrary"),
+                RangeOrAnchor::Anchor("some-anchor".to_string())
+            )
+        );
+    }
+
+    #[test]
+    fn parse_with_more_than_three_colons_ignores_everything_after_third_colon() {
+        let link_type = parse_include_path("arbitrary:5:10:17:anything:");
+        assert_eq!(
+            link_type,
+            LinkType::Include(
+                PathBuf::from("arbitrary"),
+                RangeOrAnchor::Range(LineRange::from(4..10))
+            )
+        );
+    }
 }

src/preprocess/mod.rs

@@ -1,30 +1,45 @@
 //! Book preprocessing.
 
-pub use self::links::LinkPreprocessor;
+pub use self::cmd::CmdPreprocessor;
 pub use self::index::IndexPreprocessor;
+pub use self::links::LinkPreprocessor;
 
-mod links;
+mod cmd;
 mod index;
+mod links;
 
-use book::Book;
-use config::Config;
-use errors::*;
+use crate::book::Book;
+use crate::config::Config;
+use crate::errors::*;
 
 use std::path::PathBuf;
 
 /// Extra information for a `Preprocessor` to give them more context when
 /// processing a book.
+#[derive(Debug, Clone, PartialEq, Serialize, Deserialize)]
 pub struct PreprocessorContext {
     /// The location of the book directory on disk.
     pub root: PathBuf,
     /// The book configuration (`book.toml`).
     pub config: Config,
+    /// The `Renderer` this preprocessor is being used with.
+    pub renderer: String,
+    /// The calling `mdbook` version.
+    pub mdbook_version: String,
+    #[serde(skip)]
+    __non_exhaustive: (),
 }
 
 impl PreprocessorContext {
     /// Create a new `PreprocessorContext`.
-    pub(crate) fn new(root: PathBuf, config: Config) -> Self {
-        PreprocessorContext { root, config }
+    pub(crate) fn new(root: PathBuf, config: Config, renderer: String) -> Self {
+        PreprocessorContext {
+            root,
+            config,
+            renderer,
+            mdbook_version: crate::MDBOOK_VERSION.to_string(),
+            __non_exhaustive: (),
+        }
     }
 }
 
@@ -36,5 +51,13 @@ pub trait Preprocessor {
 
     /// Run this `Preprocessor`, allowing it to update the book before it is
     /// given to a renderer.
-    fn run(&self, ctx: &PreprocessorContext, book: &mut Book) -> Result<()>;
+    fn run(&self, ctx: &PreprocessorContext, book: Book) -> Result<Book>;
+
+    /// A hint to `MDBook` whether this preprocessor is compatible with a
+    /// particular renderer.
+    ///
+    /// By default, always returns `true`.
+    fn supports_renderer(&self, _renderer: &str) -> bool {
+        true
+    }
 }

src/renderer/html_handlebars/hbs_renderer.rs

@@ -1,20 +1,19 @@
-use book::{Book, BookItem, Chapter};
-use config::{Config, HtmlConfig, Playpen};
-use errors::*;
-use renderer::html_handlebars::helpers;
-use renderer::{RenderContext, Renderer};
-use theme::{self, playpen_editor, Theme};
-use utils;
+use crate::book::{Book, BookItem};
+use crate::config::{Config, HtmlConfig, Playpen};
+use crate::errors::*;
+use crate::renderer::html_handlebars::helpers;
+use crate::renderer::{RenderContext, Renderer};
+use crate::theme::{self, playpen_editor, Theme};
+use crate::utils;
 
+use std::borrow::Cow;
 use std::collections::BTreeMap;
 use std::collections::HashMap;
-use std::fs::{self, File};
-use std::io::Read;
+use std::fs;
 use std::path::{Path, PathBuf};
 
 use handlebars::Handlebars;
 use regex::{Captures, Regex};
-use serde_json;
 
 #[derive(Default)]
 pub struct HtmlHandlebars;
@@ -27,102 +26,84 @@ impl HtmlHandlebars {
     fn render_item(
         &self,
         item: &BookItem,
-        mut ctx: RenderItemContext,
+        mut ctx: RenderItemContext<'_>,
         print_content: &mut String,
     ) -> Result<()> {
         // FIXME: This should be made DRY-er and rely less on mutable state
-        match *item {
-            BookItem::Chapter(ref ch) => {
-                let content = ch.content.clone();
-                let content = utils::render_markdown(&content, ctx.html_config.curly_quotes);
-                print_content.push_str(&content);
+        if let BookItem::Chapter(ref ch) = *item {
+            let content = ch.content.clone();
+            let content = utils::render_markdown(&content, ctx.html_config.curly_quotes);
 
-                // Update the context with data for this file
-                let path = ch.path
-                    .to_str()
-                    .chain_err(|| "Could not convert path to str")?;
-                let filepath = Path::new(&ch.path).with_extension("html");
-                let filepathstr = filepath
-                    .to_str()
-                    .chain_err(|| "Could not convert HTML path to str")?;
-                let filepathstr = utils::fs::normalize_path(filepathstr);
+            let fixed_content = utils::render_markdown_with_path(
+                &ch.content,
+                ctx.html_config.curly_quotes,
+                Some(&ch.path),
+            );
+            print_content.push_str(&fixed_content);
 
-                // "print.html" is used for the print page.
-                if ch.path == Path::new("print.md") {
-                    bail!(ErrorKind::ReservedFilenameError(ch.path.clone()));
-                };
+            // Update the context with data for this file
+            let path = ch
+                .path
+                .to_str()
+                .chain_err(|| "Could not convert path to str")?;
+            let filepath = Path::new(&ch.path).with_extension("html");
 
-                // Non-lexical lifetimes needed :'(
-                let title: String;
-                {
-                    let book_title = ctx.data
-                        .get("book_title")
-                        .and_then(serde_json::Value::as_str)
-                        .unwrap_or("");
-                    title = ch.name.clone() + " - " + book_title;
-                }
+            // "print.html" is used for the print page.
+            if ch.path == Path::new("print.md") {
+                bail!(ErrorKind::ReservedFilenameError(ch.path.clone()));
+            };
 
-                ctx.data.insert("path".to_owned(), json!(path));
-                ctx.data.insert("content".to_owned(), json!(content));
-                ctx.data.insert("chapter_title".to_owned(), json!(ch.name));
-                ctx.data.insert("title".to_owned(), json!(title));
-                ctx.data.insert(
-                    "path_to_root".to_owned(),
-                    json!(utils::fs::path_to_root(&ch.path)),
-                );
-
-                // Render the handlebars template with the data
-                debug!("Render template");
-                let rendered = ctx.handlebars.render("index", &ctx.data)?;
-
-                let rendered = self.post_process(rendered, &filepathstr, &ctx.html_config.playpen);
-
-                // Write to file
-                debug!("Creating {} ✓", filepathstr);
-                utils::fs::write_file(&ctx.destination, &filepath, &rendered.into_bytes())?;
-
-                if ctx.is_index {
-                    self.render_index(ch, &ctx.destination)?;
-                }
+            // Non-lexical lifetimes needed :'(
+            let title: String;
+            {
+                let book_title = ctx
+                    .data
+                    .get("book_title")
+                    .and_then(serde_json::Value::as_str)
+                    .unwrap_or("");
+                title = ch.name.clone() + " - " + book_title;
+            }
+
+            ctx.data.insert("path".to_owned(), json!(path));
+            ctx.data.insert("content".to_owned(), json!(content));
+            ctx.data.insert("chapter_title".to_owned(), json!(ch.name));
+            ctx.data.insert("title".to_owned(), json!(title));
+            ctx.data.insert(
+                "path_to_root".to_owned(),
+                json!(utils::fs::path_to_root(&ch.path)),
+            );
+            if let Some(ref section) = ch.number {
+                ctx.data
+                    .insert("section".to_owned(), json!(section.to_string()));
+            }
+
+            // Render the handlebars template with the data
+            debug!("Render template");
+            let rendered = ctx.handlebars.render("index", &ctx.data)?;
+
+            let rendered = self.post_process(rendered, &ctx.html_config.playpen);
+
+            // Write to file
+            debug!("Creating {}", filepath.display());
+            utils::fs::write_file(&ctx.destination, &filepath, rendered.as_bytes())?;
+
+            if ctx.is_index {
+                ctx.data.insert("path".to_owned(), json!("index.md"));
+                ctx.data.insert("path_to_root".to_owned(), json!(""));
+                ctx.data.insert("is_index".to_owned(), json!("true"));
+                let rendered_index = ctx.handlebars.render("index", &ctx.data)?;
+                let rendered_index = self.post_process(rendered_index, &ctx.html_config.playpen);
+                debug!("Creating index.html from {}", path);
+                utils::fs::write_file(&ctx.destination, "index.html", rendered_index.as_bytes())?;
             }
-            _ => {}
         }
 
         Ok(())
     }
 
-    /// Create an index.html from the first element in SUMMARY.md
-    fn render_index(&self, ch: &Chapter, destination: &Path) -> Result<()> {
-        debug!("index.html");
-
-        let mut content = String::new();
-
-        File::open(destination.join(&ch.path.with_extension("html")))?
-            .read_to_string(&mut content)?;
-
-        // This could cause a problem when someone displays
-        // code containing <base href=...>
-        // on the front page, however this case should be very very rare...
-        content = content
-            .lines()
-            .filter(|line| !line.contains("<base href="))
-            .collect::<Vec<&str>>()
-            .join("\n");
-
-        utils::fs::write_file(destination, "index.html", content.as_bytes())?;
-
-        debug!(
-            "Creating index.html from {} ✓",
-            destination.join(&ch.path.with_extension("html")).display()
-        );
-
-        Ok(())
-    }
-
-    #[cfg_attr(feature = "cargo-clippy", allow(let_and_return))]
-    fn post_process(&self, rendered: String, filepath: &str, playpen_config: &Playpen) -> String {
-        let rendered = build_header_links(&rendered, filepath);
-        let rendered = fix_anchor_links(&rendered, filepath);
+    #[cfg_attr(feature = "cargo-clippy", allow(clippy::let_and_return))]
+    fn post_process(&self, rendered: String, playpen_config: &Playpen) -> String {
+        let rendered = build_header_links(&rendered);
         let rendered = fix_code_blocks(&rendered);
         let rendered = add_playpen_pre(&rendered, playpen_config);
 
@@ -135,13 +116,19 @@ impl HtmlHandlebars {
         theme: &Theme,
         html_config: &HtmlConfig,
     ) -> Result<()> {
-        use utils::fs::write_file;
+        use crate::utils::fs::write_file;
 
-        write_file(destination, ".nojekyll", 
-            b"This file makes sure that Github Pages doesn't process mdBook's output.")?;
+        write_file(
+            destination,
+            ".nojekyll",
+            b"This file makes sure that Github Pages doesn't process mdBook's output.",
+        )?;
 
         write_file(destination, "book.js", &theme.js)?;
-        write_file(destination, "book.css", &theme.css)?;
+        write_file(destination, "css/general.css", &theme.general_css)?;
+        write_file(destination, "css/chrome.css", &theme.chrome_css)?;
+        write_file(destination, "css/print.css", &theme.print_css)?;
+        write_file(destination, "css/variables.css", &theme.variables_css)?;
         write_file(destination, "favicon.png", &theme.favicon)?;
         write_file(destination, "highlight.css", &theme.highlight_css)?;
         write_file(destination, "tomorrow-night.css", &theme.tomorrow_night_css)?;
@@ -230,6 +217,7 @@ impl HtmlHandlebars {
         );
         handlebars.register_helper("previous", Box::new(helpers::navigation::previous));
         handlebars.register_helper("next", Box::new(helpers::navigation::next));
+        handlebars.register_helper("theme_option", Box::new(helpers::theme::theme_option));
     }
 
     /// Copy across any additional CSS and JavaScript files which the book
@@ -300,6 +288,11 @@ impl Renderer for HtmlHandlebars {
         let destination = &ctx.destination;
         let book = &ctx.book;
 
+        if destination.exists() {
+            utils::fs::remove_dir_content(destination)
+                .chain_err(|| "Unable to remove stale HTML output")?;
+        }
+
         trace!("render");
         let mut handlebars = Handlebars::new();
 
@@ -343,7 +336,7 @@ impl Renderer for HtmlHandlebars {
                 handlebars: &handlebars,
                 destination: destination.to_path_buf(),
                 data: data.clone(),
-                is_index: is_index,
+                is_index,
                 html_config: html_config.clone(),
             };
             self.render_item(item, ctx, &mut print_content)?;
@@ -360,9 +353,9 @@ impl Renderer for HtmlHandlebars {
         debug!("Render template");
         let rendered = handlebars.render("index", &data)?;
 
-        let rendered = self.post_process(rendered, "print.html", &html_config.playpen);
+        let rendered = self.post_process(rendered, &html_config.playpen);
 
-        utils::fs::write_file(&destination, "print.html", &rendered.into_bytes())?;
+        utils::fs::write_file(&destination, "print.html", rendered.as_bytes())?;
         debug!("Creating print.html ✓");
 
         debug!("Copy static files");
@@ -373,7 +366,12 @@ impl Renderer for HtmlHandlebars {
 
         // Render search index
         #[cfg(feature = "search")]
-        super::search::create_files(&html_config.search.unwrap_or_default(), &destination, &book)?;
+        {
+            let search = html_config.search.unwrap_or_default();
+            if search.enable {
+                super::search::create_files(&search, &destination, &book)?;
+            }
+        }
 
         // Copy all remaining files
         utils::fs::copy_files_except_ext(&src_dir, &destination, true, &["md"])?;
@@ -389,10 +387,12 @@ fn make_data(
     html_config: &HtmlConfig,
 ) -> Result<serde_json::Map<String, serde_json::Value>> {
     trace!("make_data");
-    let html = config.html_config().unwrap_or_default();
 
     let mut data = serde_json::Map::new();
-    data.insert("language".to_owned(), json!("en"));
+    data.insert(
+        "language".to_owned(),
+        json!(config.book.language.clone().unwrap_or_default()),
+    );
     data.insert(
         "book_title".to_owned(),
         json!(config.book.title.clone().unwrap_or_default()),
@@ -406,19 +406,34 @@ fn make_data(
         data.insert("livereload".to_owned(), json!(livereload));
     }
 
+    let default_theme = match html_config.default_theme {
+        Some(ref theme) => theme,
+        None => "light",
+    };
+    data.insert("default_theme".to_owned(), json!(default_theme));
+
+    let preferred_dark_theme = match html_config.preferred_dark_theme {
+        Some(ref theme) => theme,
+        None => default_theme,
+    };
+    data.insert(
+        "preferred_dark_theme".to_owned(),
+        json!(preferred_dark_theme),
+    );
+
     // Add google analytics tag
-    if let Some(ref ga) = config.html_config().and_then(|html| html.google_analytics) {
+    if let Some(ref ga) = html_config.google_analytics {
         data.insert("google_analytics".to_owned(), json!(ga));
     }
 
-    if html.mathjax_support {
+    if html_config.mathjax_support {
         data.insert("mathjax_support".to_owned(), json!(true));
     }
 
     // Add check to see if there is an additional style
-    if !html.additional_css.is_empty() {
+    if !html_config.additional_css.is_empty() {
         let mut css = Vec::new();
-        for style in &html.additional_css {
+        for style in &html_config.additional_css {
             match style.strip_prefix(root) {
                 Ok(p) => css.push(p.to_str().expect("Could not convert to str")),
                 Err(_) => css.push(style.to_str().expect("Could not convert to str")),
@@ -428,33 +443,38 @@ fn make_data(
     }
 
     // Add check to see if there is an additional script
-    if !html.additional_js.is_empty() {
+    if !html_config.additional_js.is_empty() {
         let mut js = Vec::new();
-        for script in &html.additional_js {
+        for script in &html_config.additional_js {
             match script.strip_prefix(root) {
                 Ok(p) => js.push(p.to_str().expect("Could not convert to str")),
-                Err(_) => js.push(
-                    script
-                        .file_name()
-                        .expect("File has a file name")
-                        .to_str()
-                        .expect("Could not convert to str"),
-                ),
+                Err(_) => js.push(script.to_str().expect("Could not convert to str")),
             }
         }
         data.insert("additional_js".to_owned(), json!(js));
     }
 
-    if html.playpen.editable && html.playpen.copy_js {
+    if html_config.playpen.editable && html_config.playpen.copy_js {
         data.insert("playpen_js".to_owned(), json!(true));
+        if html_config.playpen.line_numbers {
+            data.insert("playpen_line_numbers".to_owned(), json!(true));
+        }
     }
+    if html_config.playpen.copyable {
+        data.insert("playpen_copyable".to_owned(), json!(true));
+    }
+
+    data.insert("fold_enable".to_owned(), json!((html_config.fold.enable)));
+    data.insert("fold_level".to_owned(), json!((html_config.fold.level)));
 
     let search = html_config.search.clone();
     if cfg!(feature = "search") {
-        data.insert("search_enabled".to_owned(), json!(true));
-        if search.unwrap_or_default().copy_js {
-            data.insert("search_js".to_owned(), json!(true));
-        }
+        let search = search.unwrap_or_default();
+        data.insert("search_enabled".to_owned(), json!(search.enable));
+        data.insert(
+            "search_js".to_owned(),
+            json!(search.enable && search.copy_js),
+        );
     } else if search.is_some() {
         warn!("mdBook compiled without search support, ignoring `output.html.search` table");
         warn!(
@@ -463,6 +483,16 @@ fn make_data(
         )
     }
 
+    if let Some(ref git_repository_url) = html_config.git_repository_url {
+        data.insert("git_repository_url".to_owned(), json!(git_repository_url));
+    }
+
+    let git_repository_icon = match html_config.git_repository_icon {
+        Some(ref git_repository_icon) => git_repository_icon,
+        None => "fa-github",
+    };
+    data.insert("git_repository_icon".to_owned(), json!(git_repository_icon));
+
     let mut chapters = vec![];
 
     for item in book.iter() {
@@ -475,8 +505,14 @@ fn make_data(
                     chapter.insert("section".to_owned(), json!(section.to_string()));
                 }
 
+                chapter.insert(
+                    "has_sub_items".to_owned(),
+                    json!((!ch.sub_items.is_empty()).to_string()),
+                );
+
                 chapter.insert("name".to_owned(), json!(ch.name));
-                let path = ch.path
+                let path = ch
+                    .path
                     .to_str()
                     .chain_err(|| "Could not convert path to str")?;
                 chapter.insert("path".to_owned(), json!(path));
@@ -495,30 +531,29 @@ fn make_data(
     Ok(data)
 }
 
-/// Goes through the rendered HTML, making sure all header tags are wrapped in
-/// an anchor so people can link to sections directly.
-fn build_header_links(html: &str, filepath: &str) -> String {
+/// Goes through the rendered HTML, making sure all header tags have
+/// an anchor respectively so people can link to sections directly.
+fn build_header_links(html: &str) -> String {
     let regex = Regex::new(r"<h(\d)>(.*?)</h\d>").unwrap();
     let mut id_counter = HashMap::new();
 
     regex
-        .replace_all(html, |caps: &Captures| {
+        .replace_all(html, |caps: &Captures<'_>| {
             let level = caps[1]
                 .parse()
                 .expect("Regex should ensure we only ever get numbers here");
 
-            wrap_header_with_link(level, &caps[2], &mut id_counter, filepath)
+            insert_link_into_header(level, &caps[2], &mut id_counter)
         })
         .into_owned()
 }
 
-/// Wraps a single header tag with a link, making sure each tag gets its own
+/// Insert a sinle link into a header, making sure each link gets its own
 /// unique ID by appending an auto-incremented number (if necessary).
-fn wrap_header_with_link(
+fn insert_link_into_header(
     level: usize,
     content: &str,
     id_counter: &mut HashMap<String, usize>,
-    filepath: &str,
 ) -> String {
     let raw_id = utils::id_from_content(content);
 
@@ -532,36 +567,13 @@ fn wrap_header_with_link(
     *id_count += 1;
 
     format!(
-        r##"<a class="header" href="{filepath}#{id}" id="{id}"><h{level}>{text}</h{level}></a>"##,
+        r##"<h{level}><a class="header" href="#{id}" id="{id}">{text}</a></h{level}>"##,
         level = level,
         id = id,
-        text = content,
-        filepath = filepath
+        text = content
     )
 }
 
-// anchors to the same page (href="#anchor") do not work because of
-// <base href="../"> pointing to the root folder. This function *fixes*
-// that in a very inelegant way
-fn fix_anchor_links(html: &str, filepath: &str) -> String {
-    let regex = Regex::new(r##"<a([^>]+)href="#([^"]+)"([^>]*)>"##).unwrap();
-    regex
-        .replace_all(html, |caps: &Captures| {
-            let before = &caps[1];
-            let anchor = &caps[2];
-            let after = &caps[3];
-
-            format!(
-                "<a{before}href=\"{filepath}#{anchor}\"{after}>",
-                before = before,
-                filepath = filepath,
-                anchor = anchor,
-                after = after
-            )
-        })
-        .into_owned()
-}
-
 // The rust book uses annotations for rustdoc to test code snippets,
 // like the following:
 // ```rust,should_panic
@@ -573,7 +585,7 @@ fn fix_anchor_links(html: &str, filepath: &str) -> String {
 fn fix_code_blocks(html: &str) -> String {
     let regex = Regex::new(r##"<code([^>]+)class="([^"]+)"([^>]*)>"##).unwrap();
     regex
-        .replace_all(html, |caps: &Captures| {
+        .replace_all(html, |caps: &Captures<'_>| {
             let before = &caps[1];
             let classes = &caps[2].replace(",", " ");
             let after = &caps[3];
@@ -589,31 +601,65 @@ fn fix_code_blocks(html: &str) -> String {
 }
 
 fn add_playpen_pre(html: &str, playpen_config: &Playpen) -> String {
+    let boring_line_regex = Regex::new(r"^(\s*)#(#|.)(.*)$").unwrap();
     let regex = Regex::new(r##"((?s)<code[^>]?class="([^"]+)".*?>(.*?)</code>)"##).unwrap();
     regex
-        .replace_all(html, |caps: &Captures| {
+        .replace_all(html, |caps: &Captures<'_>| {
             let text = &caps[1];
             let classes = &caps[2];
             let code = &caps[3];
 
-            if (classes.contains("language-rust") && !classes.contains("ignore"))
+            if (classes.contains("language-rust")
+                && !classes.contains("ignore")
+                && !classes.contains("noplaypen"))
                 || classes.contains("mdbook-runnable")
             {
                 // wrap the contents in an external pre block
-                if playpen_config.editable && classes.contains("editable")
-                    || text.contains("fn main") || text.contains("quick_main!")
-                {
-                    format!("<pre class=\"playpen\">{}</pre>", text)
-                } else {
-                    // we need to inject our own main
-                    let (attrs, code) = partition_source(code);
+                format!(
+                    "<pre class=\"playpen\"><code class=\"{}\">{}</code></pre>",
+                    classes,
+                    {
+                        let content: Cow<'_, str> = if playpen_config.editable
+                            && classes.contains("editable")
+                            || text.contains("fn main")
+                            || text.contains("quick_main!")
+                        {
+                            code.into()
+                        } else {
+                            // we need to inject our own main
+                            let (attrs, code) = partition_source(code);
 
-                    format!(
-                        "<pre class=\"playpen\"><code class=\"{}\">\n# \
-                         #![allow(unused_variables)]\n{}#fn main() {{\n{}#}}</code></pre>",
-                        classes, attrs, code
-                    )
-                }
+                            format!(
+                                "\n# #![allow(unused_variables)]\n{}#fn main() {{\n{}#}}",
+                                attrs, code
+                            )
+                            .into()
+                        };
+                        let mut prev_line_hidden = false;
+                        let mut result = String::with_capacity(content.len());
+                        for line in content.lines() {
+                            if let Some(caps) = boring_line_regex.captures(line) {
+                                if !prev_line_hidden && &caps[2] != "#" {
+                                    result += "<span class=\"boring\">";
+                                    prev_line_hidden = true;
+                                }
+                                result += &caps[1];
+                                if &caps[2] != " " {
+                                    result += &caps[2];
+                                }
+                                result += &caps[3];
+                            } else {
+                                if prev_line_hidden {
+                                    result += "</span>";
+                                    prev_line_hidden = false;
+                                }
+                                result += line;
+                            }
+                            result += "\n";
+                        }
+                        result
+                    }
+                )
             } else {
                 // not language-rust, so no-op
                 text.to_owned()
@@ -629,7 +675,7 @@ fn partition_source(s: &str) -> (String, String) {
 
     for line in s.lines() {
         let trimline = line.trim();
-        let header = trimline.chars().all(|c| c.is_whitespace()) || trimline.starts_with("#![");
+        let header = trimline.chars().all(char::is_whitespace) || trimline.starts_with("#![");
         if !header || after_header {
             after_header = true;
             after.push_str(line);
@@ -660,38 +706,57 @@ mod tests {
         let inputs = vec![
             (
                 "blah blah <h1>Foo</h1>",
-                r##"blah blah <a class="header" href="./some_chapter/some_section.html#foo" id="foo"><h1>Foo</h1></a>"##,
+                r##"blah blah <h1><a class="header" href="#foo" id="foo">Foo</a></h1>"##,
             ),
             (
                 "<h1>Foo</h1>",
-                r##"<a class="header" href="./some_chapter/some_section.html#foo" id="foo"><h1>Foo</h1></a>"##,
+                r##"<h1><a class="header" href="#foo" id="foo">Foo</a></h1>"##,
             ),
             (
                 "<h3>Foo^bar</h3>",
-                r##"<a class="header" href="./some_chapter/some_section.html#foobar" id="foobar"><h3>Foo^bar</h3></a>"##,
+                r##"<h3><a class="header" href="#foobar" id="foobar">Foo^bar</a></h3>"##,
             ),
             (
                 "<h4></h4>",
-                r##"<a class="header" href="./some_chapter/some_section.html#" id=""><h4></h4></a>"##,
+                r##"<h4><a class="header" href="#" id=""></a></h4>"##,
             ),
             (
                 "<h4><em>Hï</em></h4>",
-                r##"<a class="header" href="./some_chapter/some_section.html#hï" id="hï"><h4><em>Hï</em></h4></a>"##,
+                r##"<h4><a class="header" href="#hï" id="hï"><em>Hï</em></a></h4>"##,
             ),
             (
                 "<h1>Foo</h1><h3>Foo</h3>",
-                r##"<a class="header" href="./some_chapter/some_section.html#foo" id="foo"><h1>Foo</h1></a><a class="header" href="./some_chapter/some_section.html#foo-1" id="foo-1"><h3>Foo</h3></a>"##,
+                r##"<h1><a class="header" href="#foo" id="foo">Foo</a></h1><h3><a class="header" href="#foo-1" id="foo-1">Foo</a></h3>"##,
             ),
         ];
 
         for (src, should_be) in inputs {
-            let filepath = "./some_chapter/some_section.html";
-            let got = build_header_links(&src, filepath);
-            assert_eq!(got, should_be);
-
-            // This is redundant for most cases
-            let got = fix_anchor_links(&got, filepath);
+            let got = build_header_links(&src);
             assert_eq!(got, should_be);
         }
     }
+
+    #[test]
+    fn add_playpen() {
+        let inputs = [
+          ("<code class=\"language-rust\">x()</code>",
+           "<pre class=\"playpen\"><code class=\"language-rust\">\n<span class=\"boring\">#![allow(unused_variables)]\nfn main() {\n</span>x()\n<span class=\"boring\">}\n</code></pre>"),
+          ("<code class=\"language-rust\">fn main() {}</code>",
+           "<pre class=\"playpen\"><code class=\"language-rust\">fn main() {}\n</code></pre>"),
+          ("<code class=\"language-rust editable\">let s = \"foo\n # bar\n\";</code>",
+           "<pre class=\"playpen\"><code class=\"language-rust editable\">let s = \"foo\n<span class=\"boring\"> bar\n</span>\";\n</code></pre>"),
+          ("<code class=\"language-rust editable\">let s = \"foo\n ## bar\n\";</code>",
+           "<pre class=\"playpen\"><code class=\"language-rust editable\">let s = \"foo\n # bar\n\";\n</code></pre>"),
+        ];
+        for (src, should_be) in &inputs {
+            let got = add_playpen_pre(
+                src,
+                &Playpen {
+                    editable: true,
+                    ..Playpen::default()
+                },
+            );
+            assert_eq!(&*got, *should_be);
+        }
+    }
 }

src/renderer/html_handlebars/helpers/mod.rs

@@ -1,2 +1,3 @@
-pub mod toc;
 pub mod navigation;
+pub mod theme;
+pub mod toc;

src/renderer/html_handlebars/helpers/navigation.rs

@@ -1,8 +1,9 @@
-use std::path::Path;
 use std::collections::BTreeMap;
+use std::path::Path;
 
-use serde_json;
-use handlebars::{Context, Handlebars, Helper, RenderContext, RenderError, Renderable};
+use handlebars::{Context, Handlebars, Helper, Output, RenderContext, RenderError, Renderable};
+
+use crate::utils;
 
 type StringMap = BTreeMap<String, String>;
 
@@ -16,13 +17,13 @@ impl Target {
     /// Returns target if found.
     fn find(
         &self,
-        base_path: &String,
-        current_path: &String,
+        base_path: &str,
+        current_path: &str,
         current_item: &StringMap,
         previous_item: &StringMap,
     ) -> Result<Option<StringMap>, RenderError> {
-        match self {
-            &Target::Next => {
+        match *self {
+            Target::Next => {
                 let previous_path = previous_item
                     .get("path")
                     .ok_or_else(|| RenderError::new("No path found for chapter in JSON data"))?;
@@ -32,7 +33,7 @@ impl Target {
                 }
             }
 
-            &Target::Previous => {
+            Target::Previous => {
                 if current_path == base_path {
                     return Ok(Some(previous_item.clone()));
                 }
@@ -43,19 +44,46 @@ impl Target {
     }
 }
 
-fn find_chapter(rc: &mut RenderContext, target: Target) -> Result<Option<StringMap>, RenderError> {
+fn find_chapter(
+    ctx: &Context,
+    rc: &mut RenderContext<'_>,
+    target: Target,
+) -> Result<Option<StringMap>, RenderError> {
     debug!("Get data from context");
 
-    let chapters = rc.evaluate_absolute("chapters", true).and_then(|c| {
-        serde_json::value::from_value::<Vec<StringMap>>(c.clone())
+    let chapters = rc.evaluate(ctx, "@root/chapters").and_then(|c| {
+        serde_json::value::from_value::<Vec<StringMap>>(c.as_json().clone())
             .map_err(|_| RenderError::new("Could not decode the JSON data"))
     })?;
 
-    let base_path = rc.evaluate_absolute("path", true)?
+    let base_path = rc
+        .evaluate(ctx, "@root/path")?
+        .as_json()
         .as_str()
         .ok_or_else(|| RenderError::new("Type error for `path`, string expected"))?
         .replace("\"", "");
 
+    if !rc.evaluate(ctx, "@root/is_index")?.is_missing() {
+        // Special case for index.md which may be a synthetic page.
+        // Target::find won't match because there is no page with the path
+        // "index.md" (unless there really is an index.md in SUMMARY.md).
+        match target {
+            Target::Previous => return Ok(None),
+            Target::Next => match chapters
+                .iter()
+                .filter(|chapter| {
+                    // Skip things like "spacer"
+                    chapter.contains_key("path")
+                })
+                .skip(1)
+                .next()
+            {
+                Some(chapter) => return Ok(Some(chapter.clone())),
+                None => return Ok(None),
+            },
+        }
+    }
+
     let mut previous: Option<StringMap> = None;
 
     debug!("Search for chapter");
@@ -79,14 +107,27 @@ fn find_chapter(rc: &mut RenderContext, target: Target) -> Result<Option<StringM
 }
 
 fn render(
-    _h: &Helper,
+    _h: &Helper<'_, '_>,
     r: &Handlebars,
-    rc: &mut RenderContext,
+    ctx: &Context,
+    rc: &mut RenderContext<'_>,
+    out: &mut dyn Output,
     chapter: &StringMap,
 ) -> Result<(), RenderError> {
     trace!("Creating BTreeMap to inject in context");
 
     let mut context = BTreeMap::new();
+    let base_path = rc
+        .evaluate(ctx, "@root/path")?
+        .as_json()
+        .as_str()
+        .ok_or_else(|| RenderError::new("Type error for `path`, string expected"))?
+        .replace("\"", "");
+
+    context.insert(
+        "path_to_root".to_owned(),
+        json!(utils::fs::path_to_root(&base_path)),
+    );
 
     chapter
         .get("name")
@@ -109,28 +150,41 @@ fn render(
     _h.template()
         .ok_or_else(|| RenderError::new("Error with the handlebars template"))
         .and_then(|t| {
-            let mut local_rc = rc.with_context(Context::wraps(&context)?);
-            t.render(r, &mut local_rc)
+            let mut local_rc = rc.new_for_block();
+            let local_ctx = Context::wraps(&context)?;
+            t.render(r, &local_ctx, &mut local_rc, out)
         })?;
 
     Ok(())
 }
 
-pub fn previous(_h: &Helper, r: &Handlebars, rc: &mut RenderContext) -> Result<(), RenderError> {
+pub fn previous(
+    _h: &Helper<'_, '_>,
+    r: &Handlebars,
+    ctx: &Context,
+    rc: &mut RenderContext<'_>,
+    out: &mut dyn Output,
+) -> Result<(), RenderError> {
     trace!("previous (handlebars helper)");
 
-    if let Some(previous) = find_chapter(rc, Target::Previous)? {
-        render(_h, r, rc, &previous)?;
+    if let Some(previous) = find_chapter(ctx, rc, Target::Previous)? {
+        render(_h, r, ctx, rc, out, &previous)?;
     }
 
     Ok(())
 }
 
-pub fn next(_h: &Helper, r: &Handlebars, rc: &mut RenderContext) -> Result<(), RenderError> {
+pub fn next(
+    _h: &Helper<'_, '_>,
+    r: &Handlebars,
+    ctx: &Context,
+    rc: &mut RenderContext<'_>,
+    out: &mut dyn Output,
+) -> Result<(), RenderError> {
     trace!("next (handlebars helper)");
 
-    if let Some(next) = find_chapter(rc, Target::Next)? {
-        render(_h, r, rc, &next)?;
+    if let Some(next) = find_chapter(ctx, rc, Target::Next)? {
+        render(_h, r, ctx, rc, out, &next)?;
     }
 
     Ok(())
@@ -140,29 +194,29 @@ pub fn next(_h: &Helper, r: &Handlebars, rc: &mut RenderContext) -> Result<(), R
 mod tests {
     use super::*;
 
-    static TEMPLATE: &'static str =
+    static TEMPLATE: &str =
         "{{#previous}}{{title}}: {{link}}{{/previous}}|{{#next}}{{title}}: {{link}}{{/next}}";
 
     #[test]
     fn test_next_previous() {
         let data = json!({
-         "name": "two",
-         "path": "two.path",
-         "chapters": [
-            {
-               "name": "one",
-               "path": "one.path"
-            },
-            {
-               "name": "two",
-               "path": "two.path",
-            },
-            {
-               "name": "three",
-               "path": "three.path"
-            }
-         ]
-      });
+           "name": "two",
+           "path": "two.path",
+           "chapters": [
+              {
+                 "name": "one",
+                 "path": "one.path"
+              },
+              {
+                 "name": "two",
+                 "path": "two.path",
+              },
+              {
+                 "name": "three",
+                 "path": "three.path"
+              }
+           ]
+        });
 
         let mut h = Handlebars::new();
         h.register_helper("previous", Box::new(previous));
@@ -177,23 +231,23 @@ mod tests {
     #[test]
     fn test_first() {
         let data = json!({
-         "name": "one",
-         "path": "one.path",
-         "chapters": [
-            {
-               "name": "one",
-               "path": "one.path"
-            },
-            {
-               "name": "two",
-               "path": "two.path",
-            },
-            {
-               "name": "three",
-               "path": "three.path"
-            }
-         ]
-      });
+           "name": "one",
+           "path": "one.path",
+           "chapters": [
+              {
+                 "name": "one",
+                 "path": "one.path"
+              },
+              {
+                 "name": "two",
+                 "path": "two.path",
+              },
+              {
+                 "name": "three",
+                 "path": "three.path"
+              }
+           ]
+        });
 
         let mut h = Handlebars::new();
         h.register_helper("previous", Box::new(previous));
@@ -207,23 +261,23 @@ mod tests {
     #[test]
     fn test_last() {
         let data = json!({
-         "name": "three",
-         "path": "three.path",
-         "chapters": [
-            {
-               "name": "one",
-               "path": "one.path"
-            },
-            {
-               "name": "two",
-               "path": "two.path",
-            },
-            {
-               "name": "three",
-               "path": "three.path"
-            }
-         ]
-      });
+           "name": "three",
+           "path": "three.path",
+           "chapters": [
+              {
+                 "name": "one",
+                 "path": "one.path"
+              },
+              {
+                 "name": "two",
+                 "path": "two.path",
+              },
+              {
+                 "name": "three",
+                 "path": "three.path"
+              }
+           ]
+        });
 
         let mut h = Handlebars::new();
         h.register_helper("previous", Box::new(previous));

src/renderer/html_handlebars/helpers/theme.rs

@@ -0,0 +1,28 @@
+use handlebars::{Context, Handlebars, Helper, Output, RenderContext, RenderError};
+
+pub fn theme_option(
+    h: &Helper<'_, '_>,
+    _r: &Handlebars,
+    ctx: &Context,
+    rc: &mut RenderContext<'_>,
+    out: &mut dyn Output,
+) -> Result<(), RenderError> {
+    trace!("theme_option (handlebars helper)");
+
+    let param = h.param(0).and_then(|v| v.value().as_str()).ok_or_else(|| {
+        RenderError::new("Param 0 with String type is required for theme_option helper.")
+    })?;
+
+    let default_theme = rc.evaluate(ctx, "@root/default_theme")?;
+    let default_theme_name = default_theme
+        .as_json()
+        .as_str()
+        .ok_or_else(|| RenderError::new("Type error for `default_theme`, string expected"))?;
+
+    out.write(param)?;
+    if param.to_lowercase() == default_theme_name.to_lowercase() {
+        out.write(" (default)")?;
+    }
+
+    Ok(())
+}

src/renderer/html_handlebars/helpers/toc.rs

@@ -1,9 +1,10 @@
-use std::path::Path;
 use std::collections::BTreeMap;
+use std::path::Path;
 
-use serde_json;
-use handlebars::{Handlebars, Helper, HelperDef, RenderContext, RenderError};
-use pulldown_cmark::{html, Event, Parser, Tag};
+use crate::utils;
+
+use handlebars::{Context, Handlebars, Helper, HelperDef, Output, RenderContext, RenderError};
+use pulldown_cmark::{html, Event, Parser};
 
 // Handlebars helper to construct TOC
 #[derive(Clone, Copy)]
@@ -12,62 +13,103 @@ pub struct RenderToc {
 }
 
 impl HelperDef for RenderToc {
-    fn call(&self, _h: &Helper, _: &Handlebars, rc: &mut RenderContext) -> Result<(), RenderError> {
+    fn call<'reg: 'rc, 'rc>(
+        &self,
+        _h: &Helper<'reg, 'rc>,
+        _r: &'reg Handlebars,
+        ctx: &'rc Context,
+        rc: &mut RenderContext<'reg>,
+        out: &mut dyn Output,
+    ) -> Result<(), RenderError> {
         // get value from context data
         // rc.get_path() is current json parent path, you should always use it like this
         // param is the key of value you want to display
-        let chapters = rc.evaluate_absolute("chapters", true).and_then(|c| {
-            serde_json::value::from_value::<Vec<BTreeMap<String, String>>>(c.clone())
+        let chapters = rc.evaluate(ctx, "@root/chapters").and_then(|c| {
+            serde_json::value::from_value::<Vec<BTreeMap<String, String>>>(c.as_json().clone())
                 .map_err(|_| RenderError::new("Could not decode the JSON data"))
         })?;
-        let current = rc.evaluate_absolute("path", true)?
+        let current_path = rc
+            .evaluate(ctx, "@root/path")?
+            .as_json()
             .as_str()
-            .ok_or_else(|| RenderError::new("Type error for `path`, string expected"))?
+            .ok_or(RenderError::new("Type error for `path`, string expected"))?
             .replace("\"", "");
 
-        rc.writer.write_all(b"<ol class=\"chapter\">")?;
+        let current_section = rc
+            .evaluate(ctx, "@root/section")?
+            .as_json()
+            .as_str()
+            .map(str::to_owned)
+            .unwrap_or_default();
+
+        let fold_enable = rc
+            .evaluate(ctx, "@root/fold_enable")?
+            .as_json()
+            .as_bool()
+            .ok_or(RenderError::new(
+                "Type error for `fold_enable`, bool expected",
+            ))?;
+
+        let fold_level = rc
+            .evaluate(ctx, "@root/fold_level")?
+            .as_json()
+            .as_u64()
+            .ok_or(RenderError::new(
+                "Type error for `fold_level`, u64 expected",
+            ))?;
+
+        out.write("<ol class=\"chapter\">")?;
 
         let mut current_level = 1;
 
         for item in chapters {
             // Spacer
             if item.get("spacer").is_some() {
-                rc.writer.write_all(b"<li class=\"spacer\"></li>")?;
+                out.write("<li class=\"spacer\"></li>")?;
                 continue;
             }
 
-            let level = if let Some(s) = item.get("section") {
-                s.matches('.').count()
+            let (section, level) = if let Some(s) = item.get("section") {
+                (s.as_str(), s.matches('.').count())
             } else {
-                1
+                ("", 1)
+            };
+
+            let is_expanded = {
+                if !fold_enable {
+                    // Disable fold. Expand all chapters.
+                    true
+                } else if !section.is_empty() && current_section.starts_with(section) {
+                    // The section is ancestor or the current section itself.
+                    true
+                } else {
+                    // Levels that are larger than this would be folded.
+                    level - 1 < fold_level as usize
+                }
             };
 
             if level > current_level {
                 while level > current_level {
-                    rc.writer.write_all(b"<li>")?;
-                    rc.writer.write_all(b"<ol class=\"section\">")?;
+                    out.write("<li>")?;
+                    out.write("<ol class=\"section\">")?;
                     current_level += 1;
                 }
-                rc.writer.write_all(b"<li>")?;
+                write_li_open_tag(out, is_expanded, false)?;
             } else if level < current_level {
                 while level < current_level {
-                    rc.writer.write_all(b"</ol>")?;
-                    rc.writer.write_all(b"</li>")?;
+                    out.write("</ol>")?;
+                    out.write("</li>")?;
                     current_level -= 1;
                 }
-                rc.writer.write_all(b"<li>")?;
+                write_li_open_tag(out, is_expanded, false)?;
             } else {
-                rc.writer.write_all(b"<li")?;
-                if item.get("section").is_none() {
-                    rc.writer.write_all(b" class=\"affix\"")?;
-                }
-                rc.writer.write_all(b">")?;
+                write_li_open_tag(out, is_expanded, item.get("section").is_none())?;
             }
 
             // Link
             let path_exists = if let Some(path) = item.get("path") {
                 if !path.is_empty() {
-                    rc.writer.write_all(b"<a href=\"")?;
+                    out.write("<a href=\"")?;
 
                     let tmp = Path::new(item.get("path").expect("Error: path should be Some(_)"))
                         .with_extension("html")
@@ -77,14 +119,15 @@ impl HelperDef for RenderToc {
                         .replace("\\", "/");
 
                     // Add link
-                    rc.writer.write_all(tmp.as_bytes())?;
-                    rc.writer.write_all(b"\"")?;
+                    out.write(&utils::fs::path_to_root(&current_path))?;
+                    out.write(&tmp)?;
+                    out.write("\"")?;
 
-                    if path == &current {
-                        rc.writer.write_all(b" class=\"active\"")?;
+                    if path == &current_path {
+                        out.write(" class=\"active\"")?;
                     }
 
-                    rc.writer.write_all(b">")?;
+                    out.write(">")?;
                     true
                 } else {
                     false
@@ -96,9 +139,9 @@ impl HelperDef for RenderToc {
             if !self.no_section_label {
                 // Section does not necessarily exist
                 if let Some(section) = item.get("section") {
-                    rc.writer.write_all(b"<strong aria-hidden=\"true\">")?;
-                    rc.writer.write_all(section.as_bytes())?;
-                    rc.writer.write_all(b"</strong> ")?;
+                    out.write("<strong aria-hidden=\"true\">")?;
+                    out.write(&section)?;
+                    out.write("</strong> ")?;
                 }
             }
 
@@ -107,10 +150,7 @@ impl HelperDef for RenderToc {
 
                 // filter all events that are not inline code blocks
                 let parser = Parser::new(name).filter(|event| match *event {
-                    Event::Start(Tag::Code)
-                    | Event::End(Tag::Code)
-                    | Event::InlineHtml(_)
-                    | Event::Text(_) => true,
+                    Event::Code(_) | Event::InlineHtml(_) | Event::Text(_) => true,
                     _ => false,
                 });
 
@@ -119,22 +159,45 @@ impl HelperDef for RenderToc {
                 html::push_html(&mut markdown_parsed_name, parser);
 
                 // write to the handlebars template
-                rc.writer.write_all(markdown_parsed_name.as_bytes())?;
+                out.write(&markdown_parsed_name)?;
             }
 
             if path_exists {
-                rc.writer.write_all(b"</a>")?;
+                out.write("</a>")?;
             }
 
-            rc.writer.write_all(b"</li>")?;
+            // Render expand/collapse toggle
+            if let Some(flag) = item.get("has_sub_items") {
+                let has_sub_items = flag.parse::<bool>().unwrap_or_default();
+                if fold_enable && has_sub_items {
+                    out.write("<a class=\"toggle\"><div>❱</div></a>")?;
+                }
+            }
+            out.write("</li>")?;
         }
         while current_level > 1 {
-            rc.writer.write_all(b"</ol>")?;
-            rc.writer.write_all(b"</li>")?;
+            out.write("</ol>")?;
+            out.write("</li>")?;
             current_level -= 1;
         }
 
-        rc.writer.write_all(b"</ol>")?;
+        out.write("</ol>")?;
         Ok(())
     }
 }
+
+fn write_li_open_tag(
+    out: &mut dyn Output,
+    is_expanded: bool,
+    is_affix: bool,
+) -> Result<(), std::io::Error> {
+    let mut li = String::from("<li class=\"");
+    if is_expanded {
+        li.push_str("expanded ");
+    }
+    if is_affix {
+        li.push_str("affix ");
+    }
+    li.push_str("\">");
+    out.write(&li)
+}

src/renderer/html_handlebars/search.rs

@@ -1,33 +1,38 @@
-extern crate ammonia;
-extern crate elasticlunr;
-
 use std::borrow::Cow;
 use std::collections::{HashMap, HashSet};
 use std::path::Path;
 
+use elasticlunr::Index;
 use pulldown_cmark::*;
-use serde_json;
-use self::elasticlunr::Index;
 
-use book::{Book, BookItem};
-use config::Search;
-use errors::*;
-use utils;
-use theme::searcher;
+use crate::book::{Book, BookItem};
+use crate::config::Search;
+use crate::errors::*;
+use crate::theme::searcher;
+use crate::utils;
 
 /// Creates all files required for search.
 pub fn create_files(search_config: &Search, destination: &Path, book: &Book) -> Result<()> {
     let mut index = Index::new(&["title", "body", "breadcrumbs"]);
+    let mut doc_urls = Vec::with_capacity(book.sections.len());
 
     for item in book.iter() {
-        render_item(&mut index, &search_config, item)?;
+        render_item(&mut index, &search_config, &mut doc_urls, item)?;
     }
 
-    let index = write_to_js(index, &search_config)?;
+    let index = write_to_json(index, &search_config, doc_urls)?;
     debug!("Writing search index ✓");
+    if index.len() > 10_000_000 {
+        warn!("searchindex.json is very large ({} bytes)", index.len());
+    }
 
     if search_config.copy_js {
-        utils::fs::write_file(destination, "searchindex.js", index.as_bytes())?;
+        utils::fs::write_file(destination, "searchindex.json", index.as_bytes())?;
+        utils::fs::write_file(
+            destination,
+            "searchindex.js",
+            format!("Object.assign(window.search, {});", index).as_bytes(),
+        )?;
         utils::fs::write_file(destination, "searcher.js", searcher::JS)?;
         utils::fs::write_file(destination, "mark.min.js", searcher::MARK_JS)?;
         utils::fs::write_file(destination, "elasticlunr.min.js", searcher::ELASTICLUNR_JS)?;
@@ -38,18 +43,22 @@ pub fn create_files(search_config: &Search, destination: &Path, book: &Book) ->
 }
 
 /// Uses the given arguments to construct a search document, then inserts it to the given index.
-fn add_doc<'a>(
+fn add_doc(
     index: &mut Index,
-    anchor_base: &'a str,
+    doc_urls: &mut Vec<String>,
+    anchor_base: &str,
     section_id: &Option<String>,
     items: &[&str],
 ) {
-    let doc_ref: Cow<'a, str> = if let &Some(ref id) = section_id {
-        format!("{}#{}", anchor_base, id).into()
+    let url = if let Some(ref id) = *section_id {
+        Cow::Owned(format!("{}#{}", anchor_base, id))
     } else {
-        anchor_base.into()
+        Cow::Borrowed(anchor_base)
     };
-    let doc_ref = utils::collapse_whitespace(doc_ref.trim());
+    let url = utils::collapse_whitespace(url.trim());
+    let doc_ref = doc_urls.len().to_string();
+    doc_urls.push(url.into());
+
     let items = items.iter().map(|&x| utils::collapse_whitespace(x.trim()));
     index.add_doc(&doc_ref, items);
 }
@@ -58,10 +67,11 @@ fn add_doc<'a>(
 fn render_item(
     index: &mut Index,
     search_config: &Search,
+    doc_urls: &mut Vec<String>,
     item: &BookItem,
 ) -> Result<()> {
-    let chapter = match item {
-        &BookItem::Chapter(ref ch) => ch,
+    let chapter = match *item {
+        BookItem::Chapter(ref ch) => ch,
         _ => return Ok(()),
     };
 
@@ -71,27 +81,26 @@ fn render_item(
         .chain_err(|| "Could not convert HTML path to str")?;
     let anchor_base = utils::fs::normalize_path(filepath);
 
-    let mut opts = Options::empty();
-    opts.insert(OPTION_ENABLE_TABLES);
-    opts.insert(OPTION_ENABLE_FOOTNOTES);
-    let p = Parser::new_ext(&chapter.content, opts);
+    let p = utils::new_cmark_parser(&chapter.content);
 
     let mut in_header = false;
-    let max_section_depth = search_config.heading_split_level as i32;
+    let max_section_depth = i32::from(search_config.heading_split_level);
     let mut section_id = None;
     let mut heading = String::new();
     let mut body = String::new();
+    let mut html_block = String::new();
     let mut breadcrumbs = chapter.parent_names.clone();
     let mut footnote_numbers = HashMap::new();
 
     for event in p {
         match event {
             Event::Start(Tag::Header(i)) if i <= max_section_depth => {
-                if heading.len() > 0 {
+                if !heading.is_empty() {
                     // Section finished, the next header is following now
                     // Write the data to the index, and clear it for the next section
                     add_doc(
                         index,
+                        doc_urls,
                         &anchor_base,
                         &section_id,
                         &[&heading, &body, &breadcrumbs.join(" » ")],
@@ -113,6 +122,13 @@ fn render_item(
                 let number = footnote_numbers.len() + 1;
                 footnote_numbers.entry(name).or_insert(number);
             }
+            Event::Html(html) => {
+                html_block.push_str(&html);
+            }
+            Event::End(Tag::HtmlBlock) => {
+                body.push_str(&clean_html(&html_block));
+                html_block.clear();
+            }
             Event::Start(_) | Event::End(_) | Event::SoftBreak | Event::HardBreak => {
                 // Insert spaces where HTML output would usually seperate text
                 // to ensure words don't get merged together
@@ -122,14 +138,14 @@ fn render_item(
                     body.push(' ');
                 }
             }
-            Event::Text(text) => {
+            Event::Text(text) | Event::Code(text) => {
                 if in_header {
                     heading.push_str(&text);
                 } else {
                     body.push_str(&text);
                 }
             }
-            Event::Html(html) | Event::InlineHtml(html) => {
+            Event::InlineHtml(html) => {
                 body.push_str(&clean_html(&html));
             }
             Event::FootnoteReference(name) => {
@@ -137,13 +153,15 @@ fn render_item(
                 let number = footnote_numbers.entry(name).or_insert(len);
                 body.push_str(&format!(" [{}] ", number));
             }
+            Event::TaskListMarker(_checked) => {}
         }
     }
 
-    if heading.len() > 0 {
+    if !heading.is_empty() {
         // Make sure the last section is added to the index
         add_doc(
             index,
+            doc_urls,
             &anchor_base,
             &section_id,
             &[&heading, &body, &breadcrumbs.join(" » ")],
@@ -153,12 +171,9 @@ fn render_item(
     Ok(())
 }
 
-/// Exports the index and search options to a JS script which stores the index in `window.search`.
-/// Using a JS script is a workaround for CORS in `file://` URIs. It also removes the need for
-/// downloading/parsing JSON in JS.
-fn write_to_js(index: Index, search_config: &Search) -> Result<String> {
+fn write_to_json(index: Index, search_config: &Search, doc_urls: Vec<String>) -> Result<String> {
+    use elasticlunr::config::{SearchBool, SearchOptions, SearchOptionsField};
     use std::collections::BTreeMap;
-    use self::elasticlunr::config::{SearchBool, SearchOptions, SearchOptionsField};
 
     #[derive(Serialize)]
     struct ResultsOptions {
@@ -169,9 +184,11 @@ fn write_to_js(index: Index, search_config: &Search) -> Result<String> {
     #[derive(Serialize)]
     struct SearchindexJson {
         /// The options used for displaying search results
-        resultsoptions: ResultsOptions,
+        results_options: ResultsOptions,
         /// The searchoptions for elasticlunr.js
-        searchoptions: SearchOptions,
+        search_options: SearchOptions,
+        /// Used to lookup a document's URL from an integer document ref.
+        doc_urls: Vec<String>,
         /// The index for elasticlunr.js
         index: elasticlunr::Index,
     }
@@ -185,7 +202,7 @@ fn write_to_js(index: Index, search_config: &Search) -> Result<String> {
     opt.boost = Some(search_config.boost_hierarchy);
     fields.insert("breadcrumbs".into(), opt);
 
-    let searchoptions = SearchOptions {
+    let search_options = SearchOptions {
         bool: if search_config.use_boolean_and {
             SearchBool::And
         } else {
@@ -195,14 +212,15 @@ fn write_to_js(index: Index, search_config: &Search) -> Result<String> {
         fields,
     };
 
-    let resultsoptions = ResultsOptions {
+    let results_options = ResultsOptions {
         limit_results: search_config.limit_results,
         teaser_word_count: search_config.teaser_word_count,
     };
 
     let json_contents = SearchindexJson {
-        resultsoptions,
-        searchoptions,
+        results_options,
+        search_options,
+        doc_urls,
         index,
     };
 
@@ -211,7 +229,7 @@ fn write_to_js(index: Index, search_config: &Search) -> Result<String> {
     let json_contents = serde_json::to_value(&json_contents)?;
     let json_contents = serde_json::to_string(&json_contents)?;
 
-    Ok(format!("window.search = {};", json_contents))
+    Ok(json_contents)
 }
 
 fn clean_html(html: &str) -> String {

src/renderer/markdown_renderer.rs

@@ -0,0 +1,46 @@
+use crate::book::BookItem;
+use crate::errors::*;
+use crate::renderer::{RenderContext, Renderer};
+use crate::utils;
+
+use std::fs;
+
+#[derive(Default)]
+/// A renderer to output the Markdown after the preprocessors have run. Mostly useful
+/// when debugging preprocessors.
+pub struct MarkdownRenderer;
+
+impl MarkdownRenderer {
+    /// Create a new `MarkdownRenderer` instance.
+    pub fn new() -> Self {
+        MarkdownRenderer
+    }
+}
+
+impl Renderer for MarkdownRenderer {
+    fn name(&self) -> &str {
+        "markdown"
+    }
+
+    fn render(&self, ctx: &RenderContext) -> Result<()> {
+        let destination = &ctx.destination;
+        let book = &ctx.book;
+
+        if destination.exists() {
+            utils::fs::remove_dir_content(destination)
+                .chain_err(|| "Unable to remove stale Markdown output")?;
+        }
+
+        trace!("markdown render");
+        for item in book.iter() {
+            if let BookItem::Chapter(ref ch) = *item {
+                utils::fs::write_file(&ctx.destination, &ch.path, ch.content.as_bytes())?;
+            }
+        }
+
+        fs::create_dir_all(&destination)
+            .chain_err(|| "Unexpected error when constructing destination path")?;
+
+        Ok(())
+    }
+}

src/renderer/mod.rs

@@ -8,25 +8,24 @@
 //!
 //! The definition for [RenderContext] may be useful though.
 //!
-//! [For Developers]: https://rust-lang-nursery.github.io/mdBook/lib/index.html
+//! [For Developers]: https://rust-lang-nursery.github.io/mdBook/for_developers/index.html
 //! [RenderContext]: struct.RenderContext.html
 
 pub use self::html_handlebars::HtmlHandlebars;
+pub use self::markdown_renderer::MarkdownRenderer;
 
 mod html_handlebars;
+mod markdown_renderer;
 
+use shlex::Shlex;
 use std::fs;
 use std::io::{self, Read};
 use std::path::PathBuf;
 use std::process::{Command, Stdio};
-use serde_json;
-use shlex::Shlex;
 
-use errors::*;
-use config::Config;
-use book::Book;
-
-const MDBOOK_VERSION: &str = env!("CARGO_PKG_VERSION");
+use crate::book::Book;
+use crate::config::Config;
+use crate::errors::*;
 
 /// An arbitrary `mdbook` backend.
 ///
@@ -66,6 +65,8 @@ pub struct RenderContext {
     /// renderers to cache intermediate results, this directory is not
     /// guaranteed to be empty or even exist.
     pub destination: PathBuf,
+    #[serde(skip)]
+    __non_exhaustive: (),
 }
 
 impl RenderContext {
@@ -76,11 +77,12 @@ impl RenderContext {
         Q: Into<PathBuf>,
     {
         RenderContext {
-            book: book,
-            config: config,
-            version: MDBOOK_VERSION.to_string(),
+            book,
+            config,
+            version: crate::MDBOOK_VERSION.to_string(),
             root: root.into(),
             destination: destination.into(),
+            __non_exhaustive: (),
         }
     }
 
@@ -157,22 +159,27 @@ impl Renderer for CmdRenderer {
 
         let _ = fs::create_dir_all(&ctx.destination);
 
-        let mut child = match self.compose_command()?
+        let mut child = match self
+            .compose_command()?
             .stdin(Stdio::piped())
             .stdout(Stdio::inherit())
             .stderr(Stdio::inherit())
             .current_dir(&ctx.destination)
-            .spawn() {
-                Ok(c) => c,
-                Err(ref e) if e.kind() == io::ErrorKind::NotFound => {
-                    warn!("The command wasn't found, is the \"{}\" backend installed?", self.name);
-                    warn!("\tCommand: {}", self.cmd);
-                    return Ok(());
-                }
-                Err(e) => {
-                    return Err(e).chain_err(|| "Unable to start the backend")?;
-                }
-            };
+            .spawn()
+        {
+            Ok(c) => c,
+            Err(ref e) if e.kind() == io::ErrorKind::NotFound => {
+                warn!(
+                    "The command wasn't found, is the \"{}\" backend installed?",
+                    self.name
+                );
+                warn!("\tCommand: {}", self.cmd);
+                return Ok(());
+            }
+            Err(e) => {
+                return Err(e).chain_err(|| "Unable to start the backend")?;
+            }
+        };
 
         {
             let mut stdin = child.stdin.take().expect("Child has stdin");

src/theme/ayu-highlight.css

@@ -69,3 +69,11 @@ Original by Dempfi (https://github.com/dempfi/ayu)
 .hljs-strong {
   font-weight: bold;
 }
+
+.hljs-addition {
+  color: #91b362;
+}
+
+.hljs-deletion {
+  color: #d96c75;
+}

src/theme/book.js

@@ -18,13 +18,30 @@ function playpen_text(playpen) {
 (function codeSnippets() {
     // Hide Rust code lines prepended with a specific character
     var hiding_character = "#";
-    var request = fetch("https://play.rust-lang.org/meta/crates", {
-        headers: {
-            'Content-Type': "application/json",
-        },
-        method: 'POST',
-        mode: 'cors',
-    });
+
+    function fetch_with_timeout(url, options, timeout = 6000) {
+        return Promise.race([
+            fetch(url, options),
+            new Promise((_, reject) => setTimeout(() => reject(new Error('timeout')), timeout))
+        ]);
+    }
+
+    var playpens = Array.from(document.querySelectorAll(".playpen"));
+    if (playpens.length > 0) {
+        fetch_with_timeout("https://play.rust-lang.org/meta/crates", {
+            headers: {
+                'Content-Type': "application/json",
+            },
+            method: 'POST',
+            mode: 'cors',
+        })
+        .then(response => response.json())
+        .then(response => {
+            // get list of crates available in the rust playground
+            let playground_crates = response.crates.map(item => item["id"]);
+            playpens.forEach(block => handle_crate_list_update(block, playground_crates));
+        });
+    }
 
     function handle_crate_list_update(playpen_block, playground_crates) {
         // update the play buttons after receiving the response
@@ -38,6 +55,15 @@ function playpen_text(playpen) {
                 editor.addEventListener("change", function (e) {
                     update_play_button(playpen_block, playground_crates);
                 });
+                // add Ctrl-Enter command to execute rust code
+                editor.commands.addCommand({
+                    name: "run",
+                    bindKey: {
+                        win: "Ctrl-Enter",
+                        mac: "Ctrl-Enter"
+                    },
+                    exec: _editor => run_rust_code(playpen_block)
+                });
             }
         }
     }
@@ -84,34 +110,34 @@ function playpen_text(playpen) {
         }
 
         let text = playpen_text(code_block);
+        let classes = code_block.querySelector('code').classList;
+        let has_2018 = classes.contains("edition2018");
+        let edition = has_2018 ? "2018" : "2015";
 
         var params = {
-            channel: "stable",
-            mode: "debug",
-            crateType: "bin",
-            tests: false,
+            version: "stable",
+            optimize: "0",
             code: text,
-        }
+            edition: edition
+        };
 
         if (text.indexOf("#![feature") !== -1) {
-            params.channel = "nightly";
+            params.version = "nightly";
         }
 
         result_block.innerText = "Running...";
 
-        var request = fetch("https://play.rust-lang.org/execute", {
+        fetch_with_timeout("https://play.rust-lang.org/evaluate.json", {
             headers: {
                 'Content-Type': "application/json",
             },
             method: 'POST',
             mode: 'cors',
             body: JSON.stringify(params)
-        });
-
-        request
-            .then(function (response) { return response.json(); })
-            .then(function (response) { result_block.innerText = response.success ? response.stdout : response.stderr; })
-            .catch(function (error) { result_block.innerText = "Playground communication" + error.message; });
+        })
+        .then(response => response.json())
+        .then(response => result_block.innerText = response.result)
+        .catch(error => result_block.innerText = "Playground Communication: " + error.message);
     }
 
     // Syntax highlighting Configuration
@@ -144,90 +170,59 @@ function playpen_text(playpen) {
 
     Array.from(document.querySelectorAll("code.language-rust")).forEach(function (block) {
 
-        var code_block = block;
-        var pre_block = block.parentNode;
-        // hide lines
-        var lines = code_block.innerHTML.split("\n");
-        var first_non_hidden_line = false;
-        var lines_hidden = false;
-
-        for (var n = 0; n < lines.length; n++) {
-            if (lines[n].trim()[0] == hiding_character) {
-                if (first_non_hidden_line) {
-                    lines[n] = "<span class=\"hidden\">" + "\n" + lines[n].replace(/(\s*)# ?/, "$1") + "</span>";
-                }
-                else {
-                    lines[n] = "<span class=\"hidden\">" + lines[n].replace(/(\s*)# ?/, "$1") + "\n" + "</span>";
-                }
-                lines_hidden = true;
-            }
-            else if (first_non_hidden_line) {
-                lines[n] = "\n" + lines[n];
-            }
-            else {
-                first_non_hidden_line = true;
-            }
-        }
-        code_block.innerHTML = lines.join("");
-
+        var lines = Array.from(block.querySelectorAll('.boring'));
         // If no lines were hidden, return
-        if (!lines_hidden) { return; }
+        if (!lines.length) { return; }
+        block.classList.add("hide-boring");
 
         var buttons = document.createElement('div');
         buttons.className = 'buttons';
         buttons.innerHTML = "<button class=\"fa fa-expand\" title=\"Show hidden lines\" aria-label=\"Show hidden lines\"></button>";
 
         // add expand button
+        var pre_block = block.parentNode;
         pre_block.insertBefore(buttons, pre_block.firstChild);
 
         pre_block.querySelector('.buttons').addEventListener('click', function (e) {
             if (e.target.classList.contains('fa-expand')) {
-                var lines = pre_block.querySelectorAll('span.hidden');
-
                 e.target.classList.remove('fa-expand');
                 e.target.classList.add('fa-compress');
                 e.target.title = 'Hide lines';
                 e.target.setAttribute('aria-label', e.target.title);
 
-                Array.from(lines).forEach(function (line) {
-                    line.classList.remove('hidden');
-                    line.classList.add('unhidden');
-                });
+                block.classList.remove('hide-boring');
             } else if (e.target.classList.contains('fa-compress')) {
-                var lines = pre_block.querySelectorAll('span.unhidden');
-
                 e.target.classList.remove('fa-compress');
                 e.target.classList.add('fa-expand');
                 e.target.title = 'Show hidden lines';
                 e.target.setAttribute('aria-label', e.target.title);
 
-                Array.from(lines).forEach(function (line) {
-                    line.classList.remove('unhidden');
-                    line.classList.add('hidden');
-                });
+                block.classList.add('hide-boring');
             }
         });
     });
 
-    Array.from(document.querySelectorAll('pre code')).forEach(function (block) {
-        var pre_block = block.parentNode;
-        if (!pre_block.classList.contains('playpen')) {
-            var buttons = pre_block.querySelector(".buttons");
-            if (!buttons) {
-                buttons = document.createElement('div');
-                buttons.className = 'buttons';
-                pre_block.insertBefore(buttons, pre_block.firstChild);
+    if (window.playpen_copyable) {
+        Array.from(document.querySelectorAll('pre code')).forEach(function (block) {
+            var pre_block = block.parentNode;
+            if (!pre_block.classList.contains('playpen')) {
+                var buttons = pre_block.querySelector(".buttons");
+                if (!buttons) {
+                    buttons = document.createElement('div');
+                    buttons.className = 'buttons';
+                    pre_block.insertBefore(buttons, pre_block.firstChild);
+                }
+
+                var clipButton = document.createElement('button');
+                clipButton.className = 'fa fa-copy clip-button';
+                clipButton.title = 'Copy to clipboard';
+                clipButton.setAttribute('aria-label', clipButton.title);
+                clipButton.innerHTML = '<i class=\"tooltiptext\"></i>';
+
+                buttons.insertBefore(clipButton, buttons.firstChild);
             }
-
-            var clipButton = document.createElement('button');
-            clipButton.className = 'fa fa-copy clip-button';
-            clipButton.title = 'Copy to clipboard';
-            clipButton.setAttribute('aria-label', clipButton.title);
-            clipButton.innerHTML = '<i class=\"tooltiptext\"></i>';
-
-            buttons.insertBefore(clipButton, buttons.firstChild);
-        }
-    });
+        });
+    }
 
     // Process playpen code blocks
     Array.from(document.querySelectorAll(".playpen")).forEach(function (pre_block) {
@@ -245,19 +240,21 @@ function playpen_text(playpen) {
         runCodeButton.title = 'Run this code';
         runCodeButton.setAttribute('aria-label', runCodeButton.title);
 
-        var copyCodeClipboardButton = document.createElement('button');
-        copyCodeClipboardButton.className = 'fa fa-copy clip-button';
-        copyCodeClipboardButton.innerHTML = '<i class="tooltiptext"></i>';
-        copyCodeClipboardButton.title = 'Copy to clipboard';
-        copyCodeClipboardButton.setAttribute('aria-label', copyCodeClipboardButton.title);
-
         buttons.insertBefore(runCodeButton, buttons.firstChild);
-        buttons.insertBefore(copyCodeClipboardButton, buttons.firstChild);
-
         runCodeButton.addEventListener('click', function (e) {
             run_rust_code(pre_block);
         });
 
+        if (window.playpen_copyable) {
+            var copyCodeClipboardButton = document.createElement('button');
+            copyCodeClipboardButton.className = 'fa fa-copy clip-button';
+            copyCodeClipboardButton.innerHTML = '<i class="tooltiptext"></i>';
+            copyCodeClipboardButton.title = 'Copy to clipboard';
+            copyCodeClipboardButton.setAttribute('aria-label', copyCodeClipboardButton.title);
+
+            buttons.insertBefore(copyCodeClipboardButton, buttons.firstChild);
+        }
+
         let code_block = pre_block.querySelector("code");
         if (window.ace && code_block.classList.contains("editable")) {
             var undoChangesButton = document.createElement('button');
@@ -274,17 +271,6 @@ function playpen_text(playpen) {
             });
         }
     });
-
-    request
-        .then(function (response) { return response.json(); })
-        .then(function (response) {
-            // get list of crates available in the rust playground
-            let playground_crates = response.crates.map(function (item) { return item["id"]; });
-            Array.from(document.querySelectorAll(".playpen")).forEach(function (block) {
-                handle_crate_list_update(block, playground_crates);
-            });
-        });
-
 })();
 
 (function themes() {
@@ -293,9 +279,9 @@ function playpen_text(playpen) {
     var themePopup = document.getElementById('theme-list');
     var themeColorMetaTag = document.querySelector('meta[name="theme-color"]');
     var stylesheets = {
-        ayuHighlight: document.querySelector("[href='ayu-highlight.css']"),
-        tomorrowNight: document.querySelector("[href='tomorrow-night.css']"),
-        highlight: document.querySelector("[href='highlight.css']"),
+        ayuHighlight: document.querySelector("[href$='ayu-highlight.css']"),
+        tomorrowNight: document.querySelector("[href$='tomorrow-night.css']"),
+        highlight: document.querySelector("[href$='highlight.css']"),
     };
 
     function showThemes() {
@@ -310,7 +296,7 @@ function playpen_text(playpen) {
         themeToggleButton.focus();
     }
 
-    function set_theme(theme) {
+    function set_theme(theme, store = true) {
         let ace_theme;
 
         if (theme == 'coal' || theme == 'navy') {
@@ -323,13 +309,11 @@ function playpen_text(playpen) {
             stylesheets.ayuHighlight.disabled = false;
             stylesheets.tomorrowNight.disabled = true;
             stylesheets.highlight.disabled = true;
-
             ace_theme = "ace/theme/tomorrow_night";
         } else {
             stylesheets.ayuHighlight.disabled = true;
             stylesheets.tomorrowNight.disabled = true;
             stylesheets.highlight.disabled = false;
-
             ace_theme = "ace/theme/dawn";
         }
 
@@ -345,11 +329,12 @@ function playpen_text(playpen) {
 
         var previousTheme;
         try { previousTheme = localStorage.getItem('mdbook-theme'); } catch (e) { }
-        if (previousTheme === null || previousTheme === undefined) { previousTheme = 'light'; }
+        if (previousTheme === null || previousTheme === undefined) { previousTheme = default_theme; }
 
-        try { localStorage.setItem('mdbook-theme', theme); } catch (e) { }
+        if (store) {
+            try { localStorage.setItem('mdbook-theme', theme); } catch (e) { }
+        }
 
-        document.body.className = theme;
         html.classList.remove(previousTheme);
         html.classList.add(theme);
     }
@@ -357,9 +342,9 @@ function playpen_text(playpen) {
     // Set theme
     var theme;
     try { theme = localStorage.getItem('mdbook-theme'); } catch(e) { }
-    if (theme === null || theme === undefined) { theme = 'light'; }
+    if (theme === null || theme === undefined) { theme = default_theme; }
 
-    set_theme(theme);
+    set_theme(theme, false);
 
     themeToggleButton.addEventListener('click', function () {
         if (themePopup.style.display === 'block') {
@@ -376,7 +361,7 @@ function playpen_text(playpen) {
 
     themePopup.addEventListener('focusout', function(e) {
         // e.relatedTarget is null in Safari and Firefox on macOS (see workaround below)
-        if (!!e.relatedTarget && !themePopup.contains(e.relatedTarget)) {
+        if (!!e.relatedTarget && !themeToggleButton.contains(e.relatedTarget) && !themePopup.contains(e.relatedTarget)) {
             hideThemes();
         }
     });
@@ -426,8 +411,10 @@ function playpen_text(playpen) {
 (function sidebar() {
     var html = document.querySelector("html");
     var sidebar = document.getElementById("sidebar");
+    var sidebarScrollBox = document.getElementById("sidebar-scrollbox");
     var sidebarLinks = document.querySelectorAll('#sidebar a');
     var sidebarToggleButton = document.getElementById("sidebar-toggle");
+    var sidebarResizeHandle = document.getElementById("sidebar-resize-handle");
     var firstContact = null;
 
     function showSidebar() {
@@ -441,6 +428,17 @@ function playpen_text(playpen) {
         try { localStorage.setItem('mdbook-sidebar', 'visible'); } catch (e) { }
     }
 
+
+    var sidebarAnchorToggles = document.querySelectorAll('#sidebar a.toggle');
+
+    function toggleSection(ev) {
+        ev.currentTarget.parentElement.classList.toggle('expanded');
+    }
+
+    Array.from(sidebarAnchorToggles).forEach(function (el) {
+        el.addEventListener('click', toggleSection);
+    });
+
     function hideSidebar() {
         html.classList.remove('sidebar-visible')
         html.classList.add('sidebar-hidden');
@@ -467,6 +465,23 @@ function playpen_text(playpen) {
         }
     });
 
+    sidebarResizeHandle.addEventListener('mousedown', initResize, false);
+
+    function initResize(e) {
+        window.addEventListener('mousemove', resize, false);
+        window.addEventListener('mouseup', stopResize, false);
+        html.classList.add('sidebar-resizing');
+    }
+    function resize(e) {
+        document.documentElement.style.setProperty('--sidebar-width', (e.clientX - sidebar.offsetLeft) + 'px');
+    }
+    //on mouseup remove windows functions mousemove & mouseup
+    function stopResize(e) {
+        html.classList.remove('sidebar-resizing');
+        window.removeEventListener('mousemove', resize, false);
+        window.removeEventListener('mouseup', stopResize, false);
+    }
+
     document.addEventListener('touchstart', function (e) {
         firstContact = {
             x: e.touches[0].clientX,
@@ -495,7 +510,7 @@ function playpen_text(playpen) {
     // Scroll sidebar to current active section
     var activeSection = sidebar.querySelector(".active");
     if (activeSection) {
-        sidebar.scrollTop = activeSection.offsetTop;
+        sidebarScrollBox.scrollTop = activeSection.offsetTop;
     }
 })();
 
@@ -536,7 +551,7 @@ function playpen_text(playpen) {
         elem.className = 'fa fa-copy tooltipped';
     }
 
-    var clipboardSnippets = new Clipboard('.clip-button', {
+    var clipboardSnippets = new ClipboardJS('.clip-button', {
         text: function (trigger) {
             hideTooltip(trigger);
             let playpen = trigger.closest("pre");
@@ -588,6 +603,6 @@ function playpen_text(playpen) {
             menu.classList.remove('bordered');
         }
 
-        previousScrollTop = document.scrollingElement.scrollTop;
+        previousScrollTop = Math.max(document.scrollingElement.scrollTop, 0);
     }, { passive: true });
 })();

src/theme/css/chrome.css

@@ -0,0 +1,484 @@
+/* CSS for UI elements (a.k.a. chrome) */
+
+@import 'variables.css';
+
+::-webkit-scrollbar {
+    background: var(--bg);
+}
+::-webkit-scrollbar-thumb {
+    background: var(--scrollbar);
+}
+html {
+    scrollbar-color: var(--scrollbar) var(--bg);
+}
+#searchresults a,
+.content a:link,
+a:visited,
+a > .hljs {
+    color: var(--links);
+}
+
+/* Menu Bar */
+
+#menu-bar {
+    position: -webkit-sticky;
+    position: sticky;
+    top: 0;
+    z-index: 101;
+    margin: auto calc(0px - var(--page-padding));
+}
+#menu-bar > #menu-bar-sticky-container {
+    display: flex;
+    flex-wrap: wrap;
+    background-color: var(--bg);
+    border-bottom-color: var(--bg);
+    border-bottom-width: 1px;
+    border-bottom-style: solid;
+}
+.js #menu-bar > #menu-bar-sticky-container {
+    transition: transform 0.3s;
+}
+#menu-bar.bordered > #menu-bar-sticky-container  {
+    border-bottom-color: var(--table-border-color);
+}
+#menu-bar i, #menu-bar .icon-button {
+    position: relative;
+    padding: 0 8px;
+    z-index: 10;
+    line-height: var(--menu-bar-height);
+    cursor: pointer;
+    transition: color 0.5s;
+}
+@media only screen and (max-width: 420px) {
+    #menu-bar i, #menu-bar .icon-button {
+        padding: 0 5px;
+    }
+}
+
+.icon-button {
+    border: none;
+    background: none;
+    padding: 0;
+    color: inherit;
+}
+.icon-button i {
+    margin: 0;
+}
+
+.right-buttons {
+    margin: 0 15px;
+}
+.right-buttons a {
+    text-decoration: none;
+}
+
+html:not(.sidebar-visible) #menu-bar:not(:hover).folded > #menu-bar-sticky-container {
+    transform: translateY(calc(-10px - var(--menu-bar-height)));
+}
+
+.left-buttons {
+    display: flex;
+    margin: 0 5px;
+}
+.no-js .left-buttons {
+    display: none;
+}
+
+.menu-title {
+    display: inline-block;
+    font-weight: 200;
+    font-size: 20px;
+    line-height: var(--menu-bar-height);
+    text-align: center;
+    margin: 0;
+    flex: 1;
+    white-space: nowrap;
+    overflow: hidden;
+    text-overflow: ellipsis;
+}
+.js .menu-title {
+    cursor: pointer;
+}
+
+.menu-bar,
+.menu-bar:visited,
+.nav-chapters,
+.nav-chapters:visited,
+.mobile-nav-chapters,
+.mobile-nav-chapters:visited,
+.menu-bar .icon-button,
+.menu-bar a i {
+    color: var(--icons);
+}
+
+.menu-bar i:hover,
+.menu-bar .icon-button:hover,
+.nav-chapters:hover,
+.mobile-nav-chapters i:hover {
+    color: var(--icons-hover);
+}
+
+/* Nav Icons */
+
+.nav-chapters {
+    font-size: 2.5em;
+    text-align: center;
+    text-decoration: none;
+
+    position: fixed;
+    top: 0;
+    bottom: 0;
+    margin: 0;
+    max-width: 150px;
+    min-width: 90px;
+
+    display: flex;
+    justify-content: center;
+    align-content: center;
+    flex-direction: column;
+
+    transition: color 0.5s, background-color 0.5s;
+}
+
+.nav-chapters:hover {
+    text-decoration: none;
+    background-color: var(--theme-hover);
+    transition: background-color 0.15s, color 0.15s;
+}
+
+.nav-wrapper {
+    margin-top: 50px;
+    display: none;
+}
+
+.mobile-nav-chapters {
+    font-size: 2.5em;
+    text-align: center;
+    text-decoration: none;
+    width: 90px;
+    border-radius: 5px;
+    background-color: var(--sidebar-bg);
+}
+
+.previous {
+    float: left;
+}
+
+.next {
+    float: right;
+    right: var(--page-padding);
+}
+
+@media only screen and (max-width: 1080px) {
+    .nav-wide-wrapper { display: none; }
+    .nav-wrapper { display: block; }
+}
+
+@media only screen and (max-width: 1380px) {
+    .sidebar-visible .nav-wide-wrapper { display: none; }
+    .sidebar-visible .nav-wrapper { display: block; }
+}
+
+/* Inline code */
+
+:not(pre) > .hljs {
+    display: inline;
+    padding: 0.1em 0.3em;
+    border-radius: 3px;
+}
+
+:not(pre):not(a) > .hljs {
+    color: var(--inline-code-color);
+    overflow-x: initial;
+}
+
+a:hover > .hljs {
+    text-decoration: underline;
+}
+
+pre {
+    position: relative;
+}
+pre > .buttons {
+    position: absolute;
+    z-index: 100;
+    right: 5px;
+    top: 5px;
+
+    color: var(--sidebar-fg);
+    cursor: pointer;
+}
+pre > .buttons :hover {
+    color: var(--sidebar-active);
+}
+pre > .buttons i {
+    margin-left: 8px;
+}
+pre > .buttons button {
+    color: inherit;
+    background: transparent;
+    border: none;
+    cursor: inherit;
+}
+pre > .result {
+    margin-top: 10px;
+}
+
+/* Search */
+
+#searchresults a {
+    text-decoration: none;
+}
+
+mark {
+    border-radius: 2px;
+    padding: 0 3px 1px 3px;
+    margin: 0 -3px -1px -3px;
+    background-color: var(--search-mark-bg);
+    transition: background-color 300ms linear;
+    cursor: pointer;
+}
+
+mark.fade-out {
+    background-color: rgba(0,0,0,0) !important;
+    cursor: auto;
+}
+
+.searchbar-outer {
+    margin-left: auto;
+    margin-right: auto;
+    max-width: var(--content-max-width);
+}
+
+#searchbar {
+    width: 100%;
+    margin: 5px auto 0px auto;
+    padding: 10px 16px;
+    transition: box-shadow 300ms ease-in-out;
+    border: 1px solid var(--searchbar-border-color);
+    border-radius: 3px;
+    background-color: var(--searchbar-bg);
+    color: var(--searchbar-fg);
+}
+#searchbar:focus,
+#searchbar.active {
+    box-shadow: 0 0 3px var(--searchbar-shadow-color);
+}
+
+.searchresults-header {
+    font-weight: bold;
+    font-size: 1em;
+    padding: 18px 0 0 5px;
+    color: var(--searchresults-header-fg);
+}
+
+.searchresults-outer {
+    margin-left: auto;
+    margin-right: auto;
+    max-width: var(--content-max-width);
+    border-bottom: 1px dashed var(--searchresults-border-color);
+}
+
+ul#searchresults {
+    list-style: none;
+    padding-left: 20px;
+}
+ul#searchresults li {
+    margin: 10px 0px;
+    padding: 2px;
+    border-radius: 2px;
+}
+ul#searchresults li.focus {
+    background-color: var(--searchresults-li-bg);
+}
+ul#searchresults span.teaser {
+    display: block;
+    clear: both;
+    margin: 5px 0 0 20px;
+    font-size: 0.8em;
+}
+ul#searchresults span.teaser em {
+    font-weight: bold;
+    font-style: normal;
+}
+
+/* Sidebar */
+
+.sidebar {
+    position: fixed;
+    left: 0;
+    top: 0;
+    bottom: 0;
+    width: var(--sidebar-width);
+    font-size: 0.875em;
+    box-sizing: border-box;
+    -webkit-overflow-scrolling: touch;
+    overscroll-behavior-y: contain;
+    background-color: var(--sidebar-bg);
+    color: var(--sidebar-fg);
+}
+.sidebar-resizing {
+    -moz-user-select: none;
+    -webkit-user-select: none;
+    -ms-user-select: none;
+    user-select: none;
+}
+.js:not(.sidebar-resizing) .sidebar {
+    transition: transform 0.3s; /* Animation: slide away */
+}
+.sidebar code {
+    line-height: 2em;
+}
+.sidebar .sidebar-scrollbox {
+    overflow-y: auto;
+    position: absolute;
+    top: 0;
+    bottom: 0;
+    left: 0;
+    right: 0;
+    padding: 10px 10px;
+}
+.sidebar .sidebar-resize-handle {
+    position: absolute;
+    cursor: col-resize;
+    width: 0;
+    right: 0;
+    top: 0;
+    bottom: 0;
+}
+.js .sidebar .sidebar-resize-handle {
+    cursor: col-resize;
+    width: 5px;
+}
+.sidebar-hidden .sidebar {
+    transform: translateX(calc(0px - var(--sidebar-width)));
+}
+.sidebar::-webkit-scrollbar {
+    background: var(--sidebar-bg);
+}
+.sidebar::-webkit-scrollbar-thumb {
+    background: var(--scrollbar);
+}
+
+.sidebar-visible .page-wrapper {
+    transform: translateX(var(--sidebar-width));
+}
+@media only screen and (min-width: 620px) {
+    .sidebar-visible .page-wrapper {
+        transform: none;
+        margin-left: var(--sidebar-width);
+    }
+}
+
+.chapter {
+    list-style: none outside none;
+    padding-left: 0;
+    line-height: 2.2em;
+}
+
+.chapter ol {
+    width: 100%;
+}
+
+.chapter li {
+    display: flex;
+    color: var(--sidebar-non-existant);
+}
+.chapter li a {
+    display: block;
+    padding: 0;
+    text-decoration: none;
+    color: var(--sidebar-fg);
+}
+
+.chapter li a:hover {
+    color: var(--sidebar-active);
+}
+
+.chapter li a.active {
+    color: var(--sidebar-active);
+}
+
+.chapter li > a.toggle {
+    cursor: pointer;
+    display: block;
+    margin-left: auto;
+    padding: 0 10px;
+    user-select: none;
+    opacity: 0.68;
+}
+
+.chapter li > a.toggle div {
+    transition: transform 0.5s;
+}
+
+/* collapse the section */
+.chapter li:not(.expanded) + li > ol {
+    display: none;
+}
+
+.chapter li.expanded > a.toggle div {
+    transform: rotate(90deg);
+}
+
+.spacer {
+    width: 100%;
+    height: 3px;
+    margin: 5px 0px;
+}
+.chapter .spacer {
+    background-color: var(--sidebar-spacer);
+}
+
+@media (-moz-touch-enabled: 1), (pointer: coarse) {
+    .chapter li a { padding: 5px 0; }
+    .spacer { margin: 10px 0; }
+}
+
+.section {
+    list-style: none outside none;
+    padding-left: 20px;
+    line-height: 1.9em;
+}
+
+/* Theme Menu Popup */
+
+.theme-popup {
+    position: absolute;
+    left: 10px;
+    top: var(--menu-bar-height);
+    z-index: 1000;
+    border-radius: 4px;
+    font-size: 0.7em;
+    color: var(--fg);
+    background: var(--theme-popup-bg);
+    border: 1px solid var(--theme-popup-border);
+    margin: 0;
+    padding: 0;
+    list-style: none;
+    display: none;
+}
+.theme-popup .default {
+    color: var(--icons);
+}
+.theme-popup .theme {
+    width: 100%;
+    border: 0;
+    margin: 0;
+    padding: 2px 10px;
+    line-height: 25px;
+    white-space: nowrap;
+    text-align: left;
+    cursor: pointer;
+    color: inherit;
+    background: inherit;
+    font-size: inherit;
+}
+.theme-popup .theme:hover {
+    background-color: var(--theme-hover);
+}
+.theme-popup .theme:hover:first-child,
+.theme-popup .theme:hover:last-child {
+    border-top-left-radius: inherit;
+    border-top-right-radius: inherit;
+}

src/theme/css/general.css

@@ -0,0 +1,154 @@
+/* Base styles and content styles */
+
+@import 'variables.css';
+
+html {
+    font-family: "Open Sans", sans-serif;
+    color: var(--fg);
+    background-color: var(--bg);
+    text-size-adjust: none;
+}
+
+body {
+    margin: 0;
+    font-size: 1rem;
+    overflow-x: hidden;
+}
+
+code {
+    font-family: "Source Code Pro", Consolas, "Ubuntu Mono", Menlo, "DejaVu Sans Mono", monospace, monospace !important;
+    font-size: 0.875em; /* please adjust the ace font size accordingly in editor.js */
+}
+
+.left { float: left; }
+.right { float: right; }
+.boring { opacity: 0.6; }
+.hide-boring .boring { display: none; }
+.hidden { display: none; }
+
+h2, h3 { margin-top: 2.5em; }
+h4, h5 { margin-top: 2em; }
+
+.header + .header h3,
+.header + .header h4,
+.header + .header h5 {
+    margin-top: 1em;
+}
+
+h1 a.header:target::before,
+h2 a.header:target::before,
+h3 a.header:target::before,
+h4 a.header:target::before {
+    display: inline-block;
+    content: "»";
+    margin-left: -30px;
+    width: 30px;
+}
+
+h1 a.header:target,
+h2 a.header:target,
+h3 a.header:target,
+h4 a.header:target {
+    scroll-margin-top: calc(var(--menu-bar-height) + 0.5em);
+}
+
+.page {
+    outline: 0;
+    padding: 0 var(--page-padding);
+}
+.page-wrapper {
+    box-sizing: border-box;
+}
+.js:not(.sidebar-resizing) .page-wrapper {
+    transition: margin-left 0.3s ease, transform 0.3s ease; /* Animation: slide away */
+}
+
+.content {
+    overflow-y: auto;
+    padding: 0 15px;
+    padding-bottom: 50px;
+}
+.content main {
+    margin-left: auto;
+    margin-right: auto;
+    max-width: var(--content-max-width);
+}
+.content a { text-decoration: none; }
+.content a:hover { text-decoration: underline; }
+.content img { max-width: 100%; }
+.content .header:link,
+.content .header:visited {
+    color: var(--fg);
+}
+.content .header:link,
+.content .header:visited:hover {
+    text-decoration: none;
+}
+
+table {
+    margin: 0 auto;
+    border-collapse: collapse;
+}
+table td {
+    padding: 3px 20px;
+    border: 1px var(--table-border-color) solid;
+}
+table thead {
+    background: var(--table-header-bg);
+}
+table thead td {
+    font-weight: 700;
+    border: none;
+}
+table thead th {
+    padding: 3px 20px;
+}
+table thead tr {
+    border: 1px var(--table-header-bg) solid;
+}
+/* Alternate background colors for rows */
+table tbody tr:nth-child(2n) {
+    background: var(--table-alternate-bg);
+}
+
+
+blockquote {
+    margin: 20px 0;
+    padding: 0 20px;
+    color: var(--fg);
+    background-color: var(--quote-bg);
+    border-top: .1em solid var(--quote-border);
+    border-bottom: .1em solid var(--quote-border);
+}
+
+
+:not(.footnote-definition) + .footnote-definition,
+.footnote-definition + :not(.footnote-definition) {
+    margin-top: 2em;
+}
+.footnote-definition {
+    font-size: 0.9em;
+    margin: 0.5em 0;
+}
+.footnote-definition p {
+    display: inline;
+}
+
+.tooltiptext {
+    position: absolute;
+    visibility: hidden;
+    color: #fff;
+    background-color: #333;
+    transform: translateX(-50%); /* Center by moving tooltip 50% of its width left */
+    left: -8px; /* Half of the width of the icon */
+    top: -35px;
+    font-size: 0.8em;
+    text-align: center;
+    border-radius: 6px;
+    padding: 5px 8px;
+    margin: 5px;
+    z-index: 1000;
+}
+.tooltipped .tooltiptext {
+    visibility: visible;
+}

src/theme/css/print.css

@@ -0,0 +1,54 @@
+
+#sidebar,
+#menu-bar,
+.nav-chapters,
+.mobile-nav-chapters {
+    display: none;
+}
+
+#page-wrapper.page-wrapper {
+    transform: none;
+    margin-left: 0px;
+    overflow-y: initial;
+}
+
+#content {
+    max-width: none;
+    margin: 0;
+    padding: 0;
+}
+
+.page {
+    overflow-y: initial;
+}
+
+code {
+    background-color: #666666;
+    border-radius: 5px;
+
+    /* Force background to be printed in Chrome */
+    -webkit-print-color-adjust: exact;
+}
+
+pre > .buttons {
+    z-index: 2;
+}
+
+a, a:visited, a:active, a:hover {
+    color: #4183c4;
+    text-decoration: none;
+}
+
+h1, h2, h3, h4, h5, h6 {
+    page-break-inside: avoid;
+    page-break-after: avoid;
+}
+
+pre, code {
+    page-break-inside: avoid;
+    white-space: pre-wrap;
+}
+
+.fa {
+    display: none !important;
+}

src/theme/css/variables.css

@@ -0,0 +1,253 @@
+
+/* Globals */
+
+:root {
+    --sidebar-width: 300px;
+    --page-padding: 15px;
+    --content-max-width: 750px;
+    --menu-bar-height: 50px;
+}
+
+/* Themes */
+
+.ayu {
+    --bg: hsl(210, 25%, 8%);
+    --fg: #c5c5c5;
+
+    --sidebar-bg: #14191f;
+    --sidebar-fg: #c8c9db;
+    --sidebar-non-existant: #5c6773;
+    --sidebar-active: #ffb454;
+    --sidebar-spacer: #2d334f;
+
+    --scrollbar: var(--sidebar-fg);
+
+    --icons: #737480;
+    --icons-hover: #b7b9cc;
+
+    --links: #0096cf;
+
+    --inline-code-color: #ffb454;
+
+    --theme-popup-bg: #14191f;
+    --theme-popup-border: #5c6773;
+    --theme-hover: #191f26;
+
+    --quote-bg: hsl(226, 15%, 17%);
+    --quote-border: hsl(226, 15%, 22%);
+
+    --table-border-color: hsl(210, 25%, 13%);
+    --table-header-bg: hsl(210, 25%, 28%);
+    --table-alternate-bg: hsl(210, 25%, 11%);
+
+    --searchbar-border-color: #848484;
+    --searchbar-bg: #424242;
+    --searchbar-fg: #fff;
+    --searchbar-shadow-color: #d4c89f;
+    --searchresults-header-fg: #666;
+    --searchresults-border-color: #888;
+    --searchresults-li-bg: #252932;
+    --search-mark-bg: #e3b171;
+}
+
+.coal {
+    --bg: hsl(200, 7%, 8%);
+    --fg: #98a3ad;
+
+    --sidebar-bg: #292c2f;
+    --sidebar-fg: #a1adb8;
+    --sidebar-non-existant: #505254;
+    --sidebar-active: #3473ad;
+    --sidebar-spacer: #393939;
+
+    --scrollbar: var(--sidebar-fg);
+
+    --icons: #43484d;
+    --icons-hover: #b3c0cc;
+
+    --links: #2b79a2;
+
+    --inline-code-color: #c5c8c6;;
+
+    --theme-popup-bg: #141617;
+    --theme-popup-border: #43484d;
+    --theme-hover: #1f2124;
+
+    --quote-bg: hsl(234, 21%, 18%);
+    --quote-border: hsl(234, 21%, 23%);
+
+    --table-border-color: hsl(200, 7%, 13%);
+    --table-header-bg: hsl(200, 7%, 28%);
+    --table-alternate-bg: hsl(200, 7%, 11%);
+
+    --searchbar-border-color: #aaa;
+    --searchbar-bg: #b7b7b7;
+    --searchbar-fg: #000;
+    --searchbar-shadow-color: #aaa;
+    --searchresults-header-fg: #666;
+    --searchresults-border-color: #98a3ad;
+    --searchresults-li-bg: #2b2b2f;
+    --search-mark-bg: #355c7d;
+}
+
+.light {
+    --bg: hsl(0, 0%, 100%);
+    --fg: #333333;
+
+    --sidebar-bg: #fafafa;
+    --sidebar-fg: #364149;
+    --sidebar-non-existant: #aaaaaa;
+    --sidebar-active: #008cff;
+    --sidebar-spacer: #f4f4f4;
+
+    --scrollbar: #cccccc;
+
+    --icons: #cccccc;
+    --icons-hover: #333333;
+
+    --links: #4183c4;
+
+    --inline-code-color: #6e6b5e;
+
+    --theme-popup-bg: #fafafa;
+    --theme-popup-border: #cccccc;
+    --theme-hover: #e6e6e6;
+
+    --quote-bg: hsl(197, 37%, 96%);
+    --quote-border: hsl(197, 37%, 91%);
+
+    --table-border-color: hsl(0, 0%, 95%);
+    --table-header-bg: hsl(0, 0%, 80%);
+    --table-alternate-bg: hsl(0, 0%, 97%);
+
+    --searchbar-border-color: #aaa;
+    --searchbar-bg: #fafafa;
+    --searchbar-fg: #000;
+    --searchbar-shadow-color: #aaa;
+    --searchresults-header-fg: #666;
+    --searchresults-border-color: #888;
+    --searchresults-li-bg: #e4f2fe;
+    --search-mark-bg: #a2cff5;
+}
+
+.navy {
+    --bg: hsl(226, 23%, 11%);
+    --fg: #bcbdd0;
+
+    --sidebar-bg: #282d3f;
+    --sidebar-fg: #c8c9db;
+    --sidebar-non-existant: #505274;
+    --sidebar-active: #2b79a2;
+    --sidebar-spacer: #2d334f;
+
+    --scrollbar: var(--sidebar-fg);
+
+    --icons: #737480;
+    --icons-hover: #b7b9cc;
+
+    --links: #2b79a2;
+
+    --inline-code-color: #c5c8c6;;
+
+    --theme-popup-bg: #161923;
+    --theme-popup-border: #737480;
+    --theme-hover: #282e40;
+
+    --quote-bg: hsl(226, 15%, 17%);
+    --quote-border: hsl(226, 15%, 22%);
+
+    --table-border-color: hsl(226, 23%, 16%);
+    --table-header-bg: hsl(226, 23%, 31%);
+    --table-alternate-bg: hsl(226, 23%, 14%);
+
+    --searchbar-border-color: #aaa;
+    --searchbar-bg: #aeaec6;
+    --searchbar-fg: #000;
+    --searchbar-shadow-color: #aaa;
+    --searchresults-header-fg: #5f5f71;
+    --searchresults-border-color: #5c5c68;
+    --searchresults-li-bg: #242430;
+    --search-mark-bg: #a2cff5;
+}
+
+.rust {
+    --bg: hsl(60, 9%, 87%);
+    --fg: #262625;
+
+    --sidebar-bg: #3b2e2a;
+    --sidebar-fg: #c8c9db;
+    --sidebar-non-existant: #505254;
+    --sidebar-active: #e69f67;
+    --sidebar-spacer: #45373a;
+
+    --scrollbar: var(--sidebar-fg);
+
+    --icons: #737480;
+    --icons-hover: #262625;
+
+    --links: #2b79a2;
+
+    --inline-code-color: #6e6b5e;
+
+    --theme-popup-bg: #e1e1db;
+    --theme-popup-border: #b38f6b;
+    --theme-hover: #99908a;
+
+    --quote-bg: hsl(60, 5%, 75%);
+    --quote-border: hsl(60, 5%, 70%);
+
+    --table-border-color: hsl(60, 9%, 82%);
+    --table-header-bg: #b3a497;
+    --table-alternate-bg: hsl(60, 9%, 84%);
+
+    --searchbar-border-color: #aaa;
+    --searchbar-bg: #fafafa;
+    --searchbar-fg: #000;
+    --searchbar-shadow-color: #aaa;
+    --searchresults-header-fg: #666;
+    --searchresults-border-color: #888;
+    --searchresults-li-bg: #dec2a2;
+    --search-mark-bg: #e69f67;
+}
+
+@media (prefers-color-scheme: dark) {
+    .light.no-js {
+        --bg: hsl(200, 7%, 8%);
+        --fg: #98a3ad;
+
+        --sidebar-bg: #292c2f;
+        --sidebar-fg: #a1adb8;
+        --sidebar-non-existant: #505254;
+        --sidebar-active: #3473ad;
+        --sidebar-spacer: #393939;
+
+        --scrollbar: var(--sidebar-fg);
+
+        --icons: #43484d;
+        --icons-hover: #b3c0cc;
+
+        --links: #2b79a2;
+
+        --inline-code-color: #c5c8c6;;
+
+        --theme-popup-bg: #141617;
+        --theme-popup-border: #43484d;
+        --theme-hover: #1f2124;
+
+        --quote-bg: hsl(234, 21%, 18%);
+        --quote-border: hsl(234, 21%, 23%);
+
+        --table-border-color: hsl(200, 7%, 13%);
+        --table-header-bg: hsl(200, 7%, 28%);
+        --table-alternate-bg: hsl(200, 7%, 11%);
+
+        --searchbar-border-color: #aaa;
+        --searchbar-bg: #b7b7b7;
+        --searchbar-fg: #000;
+        --searchbar-shadow-color: #aaa;
+        --searchresults-header-fg: #666;
+        --searchresults-border-color: #98a3ad;
+        --searchresults-li-bg: #2b2b2f;
+        --search-mark-bg: #355c7d;
+    }
+}

src/theme/highlight.css

@@ -67,3 +67,13 @@
 .hljs-strong {
   font-weight: bold;
 }
+
+.hljs-addition {
+  color: #22863a;
+  background-color: #f0fff4;
+}
+
+.hljs-deletion {
+  color: #b31d28;
+  background-color: #ffeef0;
+}

src/theme/index.hbs

@@ -1,41 +1,51 @@
 <!DOCTYPE HTML>
-<html lang="{{ language }}" class="sidebar-visible no-js">
+<html lang="{{ language }}" class="sidebar-visible no-js {{ default_theme }}">
     <head>
         <!-- Book generated using mdBook -->
         <meta charset="UTF-8">
         <title>{{ title }}</title>
+        {{#if is_print }}
+        <meta name="robots" content="noindex" />
+        {{/if}}
+
         <meta content="text/html; charset=utf-8" http-equiv="Content-Type">
         <meta name="description" content="{{ description }}">
         <meta name="viewport" content="width=device-width, initial-scale=1">
         <meta name="theme-color" content="#ffffff" />
 
-        <base href="{{ path_to_root }}">
+        <link rel="shortcut icon" href="{{ path_to_root }}{{ favicon }}">
+        <link rel="stylesheet" href="{{ path_to_root }}css/variables.css">
+        <link rel="stylesheet" href="{{ path_to_root }}css/general.css">
+        <link rel="stylesheet" href="{{ path_to_root }}css/chrome.css">
+        <link rel="stylesheet" href="{{ path_to_root }}css/print.css" media="print">
 
-        <link rel="stylesheet" href="book.css">
+        <!-- Fonts -->
+        <link rel="stylesheet" href="{{ path_to_root }}FontAwesome/css/font-awesome.css">
         <link href="https://fonts.googleapis.com/css?family=Open+Sans:300italic,400italic,600italic,700italic,800italic,400,300,600,700,800" rel="stylesheet" type="text/css">
         <link href="https://fonts.googleapis.com/css?family=Source+Code+Pro:500" rel="stylesheet" type="text/css">
 
-        <link rel="shortcut icon" href="{{ favicon }}">
-
-        <!-- Font Awesome -->
-        <link rel="stylesheet" href="FontAwesome/css/font-awesome.css">
-
-        <link rel="stylesheet" href="highlight.css">
-        <link rel="stylesheet" href="tomorrow-night.css">
-        <link rel="stylesheet" href="ayu-highlight.css">
+        <!-- Highlight.js Stylesheets -->
+        <link rel="stylesheet" href="{{ path_to_root }}highlight.css">
+        <link rel="stylesheet" href="{{ path_to_root }}tomorrow-night.css">
+        <link rel="stylesheet" href="{{ path_to_root }}ayu-highlight.css">
 
         <!-- Custom theme stylesheets -->
         {{#each additional_css}}
-        <link rel="stylesheet" href="{{this}}">
+        <link rel="stylesheet" href="{{ ../path_to_root }}{{ this }}">
         {{/each}}
 
         {{#if mathjax_support}}
         <!-- MathJax -->
         <script async type="text/javascript" src="https://cdnjs.cloudflare.com/ajax/libs/mathjax/2.7.1/MathJax.js?config=TeX-AMS-MML_HTMLorMML"></script>
         {{/if}}
-
     </head>
-    <body class="light">
+    <body>
+        <!-- Provide site root to javascript -->
+        <script type="text/javascript">
+            var path_to_root = "{{ path_to_root }}";
+            var default_theme = window.matchMedia("(prefers-color-scheme: dark)").matches ? "{{ preferred_dark_theme }}" : "{{ default_theme }}";
+        </script>
+
         <!-- Work around some values being stored in localStorage wrapped in quotes -->
         <script type="text/javascript">
             try {
@@ -55,10 +65,13 @@
         <!-- Set the theme before any content is loaded, prevents flash -->
         <script type="text/javascript">
             var theme;
-            try { theme = localStorage.getItem('mdbook-theme'); } catch(e) { } 
-            if (theme === null || theme === undefined) { theme = 'light'; }
-            document.body.className = theme;
-            document.querySelector('html').className = theme + ' js';
+            try { theme = localStorage.getItem('mdbook-theme'); } catch(e) { }
+            if (theme === null || theme === undefined) { theme = default_theme; }
+            var html = document.querySelector('html');
+            html.classList.remove('no-js')
+            html.classList.remove('{{ default_theme }}')
+            html.classList.add(theme);
+            html.classList.add('js');
         </script>
 
         <!-- Hide / unhide sidebar before it is displayed -->
@@ -74,7 +87,10 @@
         </script>
 
         <nav id="sidebar" class="sidebar" aria-label="Table of contents">
-            {{#toc}}{{/toc}}
+            <div id="sidebar-scrollbox" class="sidebar-scrollbox">
+                {{#toc}}{{/toc}}
+            </div>
+            <div id="sidebar-resize-handle" class="sidebar-resize-handle"></div>
         </nav>
 
         <div id="page-wrapper" class="page-wrapper">
@@ -91,11 +107,11 @@
                                 <i class="fa fa-paint-brush"></i>
                             </button>
                             <ul id="theme-list" class="theme-popup" aria-label="Themes" role="menu">
-                                <li role="none"><button role="menuitem" class="theme" id="light">Light <span class="default">(default)</span></button></li>
-                                <li role="none"><button role="menuitem" class="theme" id="rust">Rust</button></li>
-                                <li role="none"><button role="menuitem" class="theme" id="coal">Coal</button></li>
-                                <li role="none"><button role="menuitem" class="theme" id="navy">Navy</button></li>
-                                <li role="none"><button role="menuitem" class="theme" id="ayu">Ayu</button></li>
+                                <li role="none"><button role="menuitem" class="theme" id="light">{{ theme_option "Light" }}</button></li>
+                                <li role="none"><button role="menuitem" class="theme" id="rust">{{ theme_option "Rust" }}</button></li>
+                                <li role="none"><button role="menuitem" class="theme" id="coal">{{ theme_option "Coal" }}</button></li>
+                                <li role="none"><button role="menuitem" class="theme" id="navy">{{ theme_option "Navy" }}</button></li>
+                                <li role="none"><button role="menuitem" class="theme" id="ayu">{{ theme_option "Ayu" }}</button></li>
                             </ul>
                             {{#if search_enabled}}
                             <button id="search-toggle" class="icon-button" type="button" title="Search. (Shortkey: s)" aria-label="Toggle Searchbar" aria-expanded="false" aria-keyshortcuts="S" aria-controls="searchbar">
@@ -104,12 +120,17 @@
                             {{/if}}
                         </div>
 
-                        <h1 class="menu-title">{{ book_title }}</h1> 
+                        <h1 class="menu-title">{{ book_title }}</h1>
 
                         <div class="right-buttons">
-                            <a href="print.html" title="Print this book" aria-label="Print this book">
+                            <a href="{{ path_to_root }}print.html" title="Print this book" aria-label="Print this book">
                                 <i id="print-button" class="fa fa-print"></i>
                             </a>
+                            {{#if git_repository_url}}
+                            <a href="{{git_repository_url}}" title="Git repository" aria-label="Git repository">
+                                <i id="git-repository-button" class="fa {{git_repository_icon}}"></i>
+                            </a>
+                            {{/if}}
                         </div>
                     </div>
                 </div>
@@ -144,13 +165,13 @@
                     <nav class="nav-wrapper" aria-label="Page navigation">
                         <!-- Mobile navigation buttons -->
                         {{#previous}}
-                            <a rel="prev" href="{{link}}" class="mobile-nav-chapters previous" title="Previous chapter" aria-label="Previous chapter" aria-keyshortcuts="Left">
+                            <a rel="prev" href="{{ path_to_root }}{{link}}" class="mobile-nav-chapters previous" title="Previous chapter" aria-label="Previous chapter" aria-keyshortcuts="Left">
                                 <i class="fa fa-angle-left"></i>
                             </a>
                         {{/previous}}
 
                         {{#next}}
-                            <a rel="next" href="{{link}}" class="mobile-nav-chapters next" title="Next chapter" aria-label="Next chapter" aria-keyshortcuts="Right">
+                            <a rel="next" href="{{ path_to_root }}{{link}}" class="mobile-nav-chapters next" title="Next chapter" aria-label="Next chapter" aria-keyshortcuts="Right">
                                 <i class="fa fa-angle-right"></i>
                             </a>
                         {{/next}}
@@ -162,13 +183,13 @@
 
             <nav class="nav-wide-wrapper" aria-label="Page navigation">
                 {{#previous}}
-                    <a href="{{link}}" class="nav-chapters previous" title="Previous chapter" aria-label="Previous chapter" aria-keyshortcuts="Left">
+                    <a href="{{ path_to_root }}{{link}}" class="nav-chapters previous" title="Previous chapter" aria-label="Previous chapter" aria-keyshortcuts="Left">
                         <i class="fa fa-angle-left"></i>
                     </a>
                 {{/previous}}
 
                 {{#next}}
-                    <a href="{{link}}" class="nav-chapters next" title="Next chapter" aria-label="Next chapter" aria-keyshortcuts="Right">
+                    <a href="{{ path_to_root }}{{link}}" class="nav-chapters next" title="Next chapter" aria-label="Next chapter" aria-keyshortcuts="Right">
                         <i class="fa fa-angle-right"></i>
                     </a>
                 {{/next}}
@@ -212,30 +233,39 @@
         </script>
         {{/if}}
 
+        {{#if playpen_line_numbers}}
+        <script type="text/javascript">
+            window.playpen_line_numbers = true;
+        </script>
+        {{/if}}
+        
+        {{#if playpen_copyable}}
+        <script type="text/javascript">
+            window.playpen_copyable = true;
+        </script>
+        {{/if}}
+
         {{#if playpen_js}}
-        <script src="ace.js" type="text/javascript" charset="utf-8"></script>
-        <script src="editor.js" type="text/javascript" charset="utf-8"></script>
-        <script src="mode-rust.js" type="text/javascript" charset="utf-8"></script>
-        <script src="theme-dawn.js" type="text/javascript" charset="utf-8"></script>
-        <script src="theme-tomorrow_night.js" type="text/javascript" charset="utf-8"></script>
+        <script src="{{ path_to_root }}ace.js" type="text/javascript" charset="utf-8"></script>
+        <script src="{{ path_to_root }}editor.js" type="text/javascript" charset="utf-8"></script>
+        <script src="{{ path_to_root }}mode-rust.js" type="text/javascript" charset="utf-8"></script>
+        <script src="{{ path_to_root }}theme-dawn.js" type="text/javascript" charset="utf-8"></script>
+        <script src="{{ path_to_root }}theme-tomorrow_night.js" type="text/javascript" charset="utf-8"></script>
         {{/if}}
 
-        {{#if search_enabled}}
-        <script src="searchindex.js" type="text/javascript" charset="utf-8"></script>
-        {{/if}}
         {{#if search_js}}
-        <script src="elasticlunr.min.js" type="text/javascript" charset="utf-8"></script>
-        <script src="mark.min.js" type="text/javascript" charset="utf-8"></script>
-        <script src="searcher.js" type="text/javascript" charset="utf-8"></script>
+        <script src="{{ path_to_root }}elasticlunr.min.js" type="text/javascript" charset="utf-8"></script>
+        <script src="{{ path_to_root }}mark.min.js" type="text/javascript" charset="utf-8"></script>
+        <script src="{{ path_to_root }}searcher.js" type="text/javascript" charset="utf-8"></script>
         {{/if}}
 
-        <script src="clipboard.min.js" type="text/javascript" charset="utf-8"></script>
-        <script src="highlight.js" type="text/javascript" charset="utf-8"></script>
-        <script src="book.js" type="text/javascript" charset="utf-8"></script>
+        <script src="{{ path_to_root }}clipboard.min.js" type="text/javascript" charset="utf-8"></script>
+        <script src="{{ path_to_root }}highlight.js" type="text/javascript" charset="utf-8"></script>
+        <script src="{{ path_to_root }}book.js" type="text/javascript" charset="utf-8"></script>
 
         <!-- Custom JS scripts -->
         {{#each additional_js}}
-        <script type="text/javascript" src="{{this}}"></script>
+        <script type="text/javascript" src="{{ ../path_to_root }}{{this}}"></script>
         {{/each}}
 
         {{#if is_print}}

src/theme/mod.rs

@@ -5,35 +5,33 @@ pub mod playpen_editor;
 #[cfg(feature = "search")]
 pub mod searcher;
 
-use std::path::Path;
 use std::fs::File;
 use std::io::Read;
+use std::path::Path;
 
-use errors::*;
+use crate::errors::*;
 
-pub static INDEX: &'static [u8] = include_bytes!("index.hbs");
-pub static HEADER: &'static [u8] = include_bytes!("header.hbs");
-pub static CSS: &'static [u8] = include_bytes!("book.css");
-pub static FAVICON: &'static [u8] = include_bytes!("favicon.png");
-pub static JS: &'static [u8] = include_bytes!("book.js");
-pub static HIGHLIGHT_JS: &'static [u8] = include_bytes!("highlight.js");
-pub static TOMORROW_NIGHT_CSS: &'static [u8] = include_bytes!("tomorrow-night.css");
-pub static HIGHLIGHT_CSS: &'static [u8] = include_bytes!("highlight.css");
-pub static AYU_HIGHLIGHT_CSS: &'static [u8] = include_bytes!("ayu-highlight.css");
-pub static CLIPBOARD_JS: &'static [u8] = include_bytes!("clipboard.min.js");
-pub static FONT_AWESOME: &'static [u8] = include_bytes!("FontAwesome/css/font-awesome.min.css");
-pub static FONT_AWESOME_EOT: &'static [u8] =
-    include_bytes!("FontAwesome/fonts/fontawesome-webfont.eot");
-pub static FONT_AWESOME_SVG: &'static [u8] =
-    include_bytes!("FontAwesome/fonts/fontawesome-webfont.svg");
-pub static FONT_AWESOME_TTF: &'static [u8] =
-    include_bytes!("FontAwesome/fonts/fontawesome-webfont.ttf");
-pub static FONT_AWESOME_WOFF: &'static [u8] =
-    include_bytes!("FontAwesome/fonts/fontawesome-webfont.woff");
-pub static FONT_AWESOME_WOFF2: &'static [u8] =
+pub static INDEX: &[u8] = include_bytes!("index.hbs");
+pub static HEADER: &[u8] = include_bytes!("header.hbs");
+pub static CHROME_CSS: &[u8] = include_bytes!("css/chrome.css");
+pub static GENERAL_CSS: &[u8] = include_bytes!("css/general.css");
+pub static PRINT_CSS: &[u8] = include_bytes!("css/print.css");
+pub static VARIABLES_CSS: &[u8] = include_bytes!("css/variables.css");
+pub static FAVICON: &[u8] = include_bytes!("favicon.png");
+pub static JS: &[u8] = include_bytes!("book.js");
+pub static HIGHLIGHT_JS: &[u8] = include_bytes!("highlight.js");
+pub static TOMORROW_NIGHT_CSS: &[u8] = include_bytes!("tomorrow-night.css");
+pub static HIGHLIGHT_CSS: &[u8] = include_bytes!("highlight.css");
+pub static AYU_HIGHLIGHT_CSS: &[u8] = include_bytes!("ayu-highlight.css");
+pub static CLIPBOARD_JS: &[u8] = include_bytes!("clipboard.min.js");
+pub static FONT_AWESOME: &[u8] = include_bytes!("FontAwesome/css/font-awesome.min.css");
+pub static FONT_AWESOME_EOT: &[u8] = include_bytes!("FontAwesome/fonts/fontawesome-webfont.eot");
+pub static FONT_AWESOME_SVG: &[u8] = include_bytes!("FontAwesome/fonts/fontawesome-webfont.svg");
+pub static FONT_AWESOME_TTF: &[u8] = include_bytes!("FontAwesome/fonts/fontawesome-webfont.ttf");
+pub static FONT_AWESOME_WOFF: &[u8] = include_bytes!("FontAwesome/fonts/fontawesome-webfont.woff");
+pub static FONT_AWESOME_WOFF2: &[u8] =
     include_bytes!("FontAwesome/fonts/fontawesome-webfont.woff2");
-pub static FONT_AWESOME_OTF: &'static [u8] = include_bytes!("FontAwesome/fonts/FontAwesome.otf");
-
+pub static FONT_AWESOME_OTF: &[u8] = include_bytes!("FontAwesome/fonts/FontAwesome.otf");
 
 /// The `Theme` struct should be used instead of the static variables because
 /// the `new()` method will look if the user has a theme directory in their
@@ -45,7 +43,10 @@ pub static FONT_AWESOME_OTF: &'static [u8] = include_bytes!("FontAwesome/fonts/F
 pub struct Theme {
     pub index: Vec<u8>,
     pub header: Vec<u8>,
-    pub css: Vec<u8>,
+    pub chrome_css: Vec<u8>,
+    pub general_css: Vec<u8>,
+    pub print_css: Vec<u8>,
+    pub variables_css: Vec<u8>,
     pub favicon: Vec<u8>,
     pub js: Vec<u8>,
     pub highlight_css: Vec<u8>,
@@ -73,13 +74,25 @@ impl Theme {
                 (theme_dir.join("index.hbs"), &mut theme.index),
                 (theme_dir.join("header.hbs"), &mut theme.header),
                 (theme_dir.join("book.js"), &mut theme.js),
-                (theme_dir.join("book.css"), &mut theme.css),
+                (theme_dir.join("css/chrome.css"), &mut theme.chrome_css),
+                (theme_dir.join("css/general.css"), &mut theme.general_css),
+                (theme_dir.join("css/print.css"), &mut theme.print_css),
+                (
+                    theme_dir.join("css/variables.css"),
+                    &mut theme.variables_css,
+                ),
                 (theme_dir.join("favicon.png"), &mut theme.favicon),
                 (theme_dir.join("highlight.js"), &mut theme.highlight_js),
                 (theme_dir.join("clipboard.min.js"), &mut theme.clipboard_js),
                 (theme_dir.join("highlight.css"), &mut theme.highlight_css),
-                (theme_dir.join("tomorrow-night.css"), &mut theme.tomorrow_night_css),
-                (theme_dir.join("ayu-highlight.css"), &mut theme.ayu_highlight_css),
+                (
+                    theme_dir.join("tomorrow-night.css"),
+                    &mut theme.tomorrow_night_css,
+                ),
+                (
+                    theme_dir.join("ayu-highlight.css"),
+                    &mut theme.ayu_highlight_css,
+                ),
             ];
 
             for (filename, dest) in files {
@@ -102,7 +115,10 @@ impl Default for Theme {
         Theme {
             index: INDEX.to_owned(),
             header: HEADER.to_owned(),
-            css: CSS.to_owned(),
+            chrome_css: CHROME_CSS.to_owned(),
+            general_css: GENERAL_CSS.to_owned(),
+            print_css: PRINT_CSS.to_owned(),
+            variables_css: VARIABLES_CSS.to_owned(),
             favicon: FAVICON.to_owned(),
             js: JS.to_owned(),
             highlight_css: HIGHLIGHT_CSS.to_owned(),
@@ -130,12 +146,12 @@ fn load_file_contents<P: AsRef<Path>>(filename: P, dest: &mut Vec<u8>) -> Result
     Ok(())
 }
 
-
 #[cfg(test)]
 mod tests {
     use super::*;
-    use tempfile::Builder as TempFileBuilder;
+    use std::fs;
     use std::path::PathBuf;
+    use tempfile::Builder as TempFileBuilder;
 
     #[test]
     fn theme_uses_defaults_with_nonexistent_src_dir() {
@@ -150,21 +166,28 @@ mod tests {
 
     #[test]
     fn theme_dir_overrides_defaults() {
-        // Get all the non-Rust files in the theme directory
-        let special_files = PathBuf::from(env!("CARGO_MANIFEST_DIR"))
-            .join("src/theme")
-            .read_dir()
-            .unwrap()
-            .filter_map(|f| f.ok())
-            .map(|f| f.path())
-            .filter(|p| p.is_file() && !p.ends_with(".rs"));
+        let files = [
+            "index.hbs",
+            "header.hbs",
+            "favicon.png",
+            "css/chrome.css",
+            "css/general.css",
+            "css/print.css",
+            "css/variables.css",
+            "book.js",
+            "highlight.js",
+            "tomorrow-night.css",
+            "highlight.css",
+            "ayu-highlight.css",
+            "clipboard.min.js",
+        ];
 
-        let temp = TempFileBuilder::new().prefix("mdbook").tempdir().unwrap();
+        let temp = TempFileBuilder::new().prefix("mdbook-").tempdir().unwrap();
+        fs::create_dir(temp.path().join("css")).unwrap();
 
         // "touch" all of the special files so we have empty copies
-        for special_file in special_files {
-            let filename = temp.path().join(special_file.file_name().unwrap());
-            let _ = File::create(&filename);
+        for file in &files {
+            File::create(&temp.path().join(file)).unwrap();
         }
 
         let got = Theme::new(temp.path());
@@ -172,7 +195,10 @@ mod tests {
         let empty = Theme {
             index: Vec::new(),
             header: Vec::new(),
-            css: Vec::new(),
+            chrome_css: Vec::new(),
+            general_css: Vec::new(),
+            print_css: Vec::new(),
+            variables_css: Vec::new(),
             favicon: Vec::new(),
             js: Vec::new(),
             highlight_css: Vec::new(),

src/theme/playpen_editor/editor.js

@@ -6,13 +6,16 @@ window.editors = [];
     }
 
     Array.from(document.querySelectorAll('.editable')).forEach(function(editable) {
+        let display_line_numbers = window.playpen_line_numbers || false;
+
         let editor = ace.edit(editable);
             editor.setOptions({
             highlightActiveLine: false,
             showPrintMargin: false,
-            showLineNumbers: false,
-            showGutter: false,
-            maxLines: Infinity
+            showLineNumbers: display_line_numbers,
+            showGutter: display_line_numbers,
+            maxLines: Infinity,
+            fontSize: "0.875em" // please adjust the font size of the code in general.css
         });
 
         editor.$blockScrolling = Infinity;

src/theme/playpen_editor/mod.rs

@@ -1,7 +1,7 @@
 //! Theme dependencies for the playpen editor.
 
-pub static JS: &'static [u8] = include_bytes!("editor.js");
-pub static ACE_JS: &'static [u8] = include_bytes!("ace.js");
-pub static MODE_RUST_JS: &'static [u8] = include_bytes!("mode-rust.js");
-pub static THEME_DAWN_JS: &'static [u8] = include_bytes!("theme-dawn.js");
-pub static THEME_TOMORROW_NIGHT_JS: &'static [u8] = include_bytes!("theme-tomorrow_night.js");
+pub static JS: &[u8] = include_bytes!("editor.js");
+pub static ACE_JS: &[u8] = include_bytes!("ace.js");
+pub static MODE_RUST_JS: &[u8] = include_bytes!("mode-rust.js");
+pub static THEME_DAWN_JS: &[u8] = include_bytes!("theme-dawn.js");
+pub static THEME_TOMORROW_NIGHT_JS: &[u8] = include_bytes!("theme-tomorrow_night.js");

src/theme/playpen_editor/theme-dawn.js

@@ -1 +1,7 @@
-ace.define("ace/theme/dawn",["require","exports","module","ace/lib/dom"],function(e,t,n){t.isDark=!1,t.cssClass="ace-dawn",t.cssText=".ace-dawn .ace_gutter {background: #ebebeb;color: #333}.ace-dawn .ace_print-margin {width: 1px;background: #e8e8e8}.ace-dawn {background-color: #F9F9F9;color: #080808}.ace-dawn .ace_cursor {color: #000000}.ace-dawn .ace_marker-layer .ace_selection {background: rgba(39, 95, 255, 0.30)}.ace-dawn.ace_multiselect .ace_selection.ace_start {box-shadow: 0 0 3px 0px #F9F9F9;}.ace-dawn .ace_marker-layer .ace_step {background: rgb(255, 255, 0)}.ace-dawn .ace_marker-layer .ace_bracket {margin: -1px 0 0 -1px;border: 1px solid rgba(75, 75, 126, 0.50)}.ace-dawn .ace_marker-layer .ace_active-line {background: rgba(36, 99, 180, 0.12)}.ace-dawn .ace_gutter-active-line {background-color : #dcdcdc}.ace-dawn .ace_marker-layer .ace_selected-word {border: 1px solid rgba(39, 95, 255, 0.30)}.ace-dawn .ace_invisible {color: rgba(75, 75, 126, 0.50)}.ace-dawn .ace_keyword,.ace-dawn .ace_meta {color: #794938}.ace-dawn .ace_constant,.ace-dawn .ace_constant.ace_character,.ace-dawn .ace_constant.ace_character.ace_escape,.ace-dawn .ace_constant.ace_other {color: #811F24}.ace-dawn .ace_invalid.ace_illegal {text-decoration: underline;font-style: italic;color: #F8F8F8;background-color: #B52A1D}.ace-dawn .ace_invalid.ace_deprecated {text-decoration: underline;font-style: italic;color: #B52A1D}.ace-dawn .ace_support {color: #691C97}.ace-dawn .ace_support.ace_constant {color: #B4371F}.ace-dawn .ace_fold {background-color: #794938;border-color: #080808}.ace-dawn .ace_list,.ace-dawn .ace_markup.ace_list,.ace-dawn .ace_support.ace_function {color: #693A17}.ace-dawn .ace_storage {font-style: italic;color: #A71D5D}.ace-dawn .ace_string {color: #0B6125}.ace-dawn .ace_string.ace_regexp {color: #CF5628}.ace-dawn .ace_comment {font-style: italic;color: #5A525F}.ace-dawn .ace_heading,.ace-dawn .ace_markup.ace_heading {color: #19356D}.ace-dawn .ace_variable {color: #234A97}.ace-dawn .ace_indent-guide {background: url(data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAACCAYAAACZgbYnAAAAEklEQVQImWNgYGBgYLh/5+x/AAizA4hxNNsZAAAAAElFTkSuQmCC) right repeat-y}";var r=e("../lib/dom");r.importCssString(t.cssText,t.cssClass)})
+ace.define("ace/theme/dawn",["require","exports","module","ace/lib/dom"],function(e,t,n){t.isDark=!1,t.cssClass="ace-dawn",t.cssText=".ace-dawn .ace_gutter {background: #ebebeb;color: #333}.ace-dawn .ace_print-margin {width: 1px;background: #e8e8e8}.ace-dawn {background-color: #F9F9F9;color: #080808}.ace-dawn .ace_cursor {color: #000000}.ace-dawn .ace_marker-layer .ace_selection {background: rgba(39, 95, 255, 0.30)}.ace-dawn.ace_multiselect .ace_selection.ace_start {box-shadow: 0 0 3px 0px #F9F9F9;}.ace-dawn .ace_marker-layer .ace_step {background: rgb(255, 255, 0)}.ace-dawn .ace_marker-layer .ace_bracket {margin: -1px 0 0 -1px;border: 1px solid rgba(75, 75, 126, 0.50)}.ace-dawn .ace_marker-layer .ace_active-line {background: rgba(36, 99, 180, 0.12)}.ace-dawn .ace_gutter-active-line {background-color : #dcdcdc}.ace-dawn .ace_marker-layer .ace_selected-word {border: 1px solid rgba(39, 95, 255, 0.30)}.ace-dawn .ace_invisible {color: rgba(75, 75, 126, 0.50)}.ace-dawn .ace_keyword,.ace-dawn .ace_meta {color: #794938}.ace-dawn .ace_constant,.ace-dawn .ace_constant.ace_character,.ace-dawn .ace_constant.ace_character.ace_escape,.ace-dawn .ace_constant.ace_other {color: #811F24}.ace-dawn .ace_invalid.ace_illegal {text-decoration: underline;font-style: italic;color: #F8F8F8;background-color: #B52A1D}.ace-dawn .ace_invalid.ace_deprecated {text-decoration: underline;font-style: italic;color: #B52A1D}.ace-dawn .ace_support {color: #691C97}.ace-dawn .ace_support.ace_constant {color: #B4371F}.ace-dawn .ace_fold {background-color: #794938;border-color: #080808}.ace-dawn .ace_list,.ace-dawn .ace_markup.ace_list,.ace-dawn .ace_support.ace_function {color: #693A17}.ace-dawn .ace_storage {font-style: italic;color: #A71D5D}.ace-dawn .ace_string {color: #0B6125}.ace-dawn .ace_string.ace_regexp {color: #CF5628}.ace-dawn .ace_comment {font-style: italic;color: #5A525F}.ace-dawn .ace_heading,.ace-dawn .ace_markup.ace_heading {color: #19356D}.ace-dawn .ace_variable {color: #234A97}.ace-dawn .ace_indent-guide {background: url(data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAACCAYAAACZgbYnAAAAEklEQVQImWNgYGBgYLh/5+x/AAizA4hxNNsZAAAAAElFTkSuQmCC) right repeat-y}";var r=e("../lib/dom");r.importCssString(t.cssText,t.cssClass)});                (function() {
+                    ace.require(["ace/theme/dawn"], function(m) {
+                        if (typeof module == "object" && typeof exports == "object" && module) {
+                            module.exports = m;
+                        }
+                    });
+                })();

src/theme/playpen_editor/theme-tomorrow_night.js

@@ -1 +1,7 @@
-ace.define("ace/theme/tomorrow_night",["require","exports","module","ace/lib/dom"],function(e,t,n){t.isDark=!0,t.cssClass="ace-tomorrow-night",t.cssText=".ace-tomorrow-night .ace_gutter {background: #25282c;color: #C5C8C6}.ace-tomorrow-night .ace_print-margin {width: 1px;background: #25282c}.ace-tomorrow-night {background-color: #1D1F21;color: #C5C8C6}.ace-tomorrow-night .ace_cursor {color: #AEAFAD}.ace-tomorrow-night .ace_marker-layer .ace_selection {background: #373B41}.ace-tomorrow-night.ace_multiselect .ace_selection.ace_start {box-shadow: 0 0 3px 0px #1D1F21;}.ace-tomorrow-night .ace_marker-layer .ace_step {background: rgb(102, 82, 0)}.ace-tomorrow-night .ace_marker-layer .ace_bracket {margin: -1px 0 0 -1px;border: 1px solid #4B4E55}.ace-tomorrow-night .ace_marker-layer .ace_active-line {background: #282A2E}.ace-tomorrow-night .ace_gutter-active-line {background-color: #282A2E}.ace-tomorrow-night .ace_marker-layer .ace_selected-word {border: 1px solid #373B41}.ace-tomorrow-night .ace_invisible {color: #4B4E55}.ace-tomorrow-night .ace_keyword,.ace-tomorrow-night .ace_meta,.ace-tomorrow-night .ace_storage,.ace-tomorrow-night .ace_storage.ace_type,.ace-tomorrow-night .ace_support.ace_type {color: #B294BB}.ace-tomorrow-night .ace_keyword.ace_operator {color: #8ABEB7}.ace-tomorrow-night .ace_constant.ace_character,.ace-tomorrow-night .ace_constant.ace_language,.ace-tomorrow-night .ace_constant.ace_numeric,.ace-tomorrow-night .ace_keyword.ace_other.ace_unit,.ace-tomorrow-night .ace_support.ace_constant,.ace-tomorrow-night .ace_variable.ace_parameter {color: #DE935F}.ace-tomorrow-night .ace_constant.ace_other {color: #CED1CF}.ace-tomorrow-night .ace_invalid {color: #CED2CF;background-color: #DF5F5F}.ace-tomorrow-night .ace_invalid.ace_deprecated {color: #CED2CF;background-color: #B798BF}.ace-tomorrow-night .ace_fold {background-color: #81A2BE;border-color: #C5C8C6}.ace-tomorrow-night .ace_entity.ace_name.ace_function,.ace-tomorrow-night .ace_support.ace_function,.ace-tomorrow-night .ace_variable {color: #81A2BE}.ace-tomorrow-night .ace_support.ace_class,.ace-tomorrow-night .ace_support.ace_type {color: #F0C674}.ace-tomorrow-night .ace_heading,.ace-tomorrow-night .ace_markup.ace_heading,.ace-tomorrow-night .ace_string {color: #B5BD68}.ace-tomorrow-night .ace_entity.ace_name.ace_tag,.ace-tomorrow-night .ace_entity.ace_other.ace_attribute-name,.ace-tomorrow-night .ace_meta.ace_tag,.ace-tomorrow-night .ace_string.ace_regexp,.ace-tomorrow-night .ace_variable {color: #CC6666}.ace-tomorrow-night .ace_comment {color: #969896}.ace-tomorrow-night .ace_indent-guide {background: url(data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAACCAYAAACZgbYnAAAAEklEQVQImWNgYGBgYHB3d/8PAAOIAdULw8qMAAAAAElFTkSuQmCC) right repeat-y}";var r=e("../lib/dom");r.importCssString(t.cssText,t.cssClass)})
+ace.define("ace/theme/tomorrow_night",["require","exports","module","ace/lib/dom"],function(e,t,n){t.isDark=!0,t.cssClass="ace-tomorrow-night",t.cssText=".ace-tomorrow-night .ace_gutter {background: #25282c;color: #C5C8C6}.ace-tomorrow-night .ace_print-margin {width: 1px;background: #25282c}.ace-tomorrow-night {background-color: #1D1F21;color: #C5C8C6}.ace-tomorrow-night .ace_cursor {color: #AEAFAD}.ace-tomorrow-night .ace_marker-layer .ace_selection {background: #373B41}.ace-tomorrow-night.ace_multiselect .ace_selection.ace_start {box-shadow: 0 0 3px 0px #1D1F21;}.ace-tomorrow-night .ace_marker-layer .ace_step {background: rgb(102, 82, 0)}.ace-tomorrow-night .ace_marker-layer .ace_bracket {margin: -1px 0 0 -1px;border: 1px solid #4B4E55}.ace-tomorrow-night .ace_marker-layer .ace_active-line {background: #282A2E}.ace-tomorrow-night .ace_gutter-active-line {background-color: #282A2E}.ace-tomorrow-night .ace_marker-layer .ace_selected-word {border: 1px solid #373B41}.ace-tomorrow-night .ace_invisible {color: #4B4E55}.ace-tomorrow-night .ace_keyword,.ace-tomorrow-night .ace_meta,.ace-tomorrow-night .ace_storage,.ace-tomorrow-night .ace_storage.ace_type,.ace-tomorrow-night .ace_support.ace_type {color: #B294BB}.ace-tomorrow-night .ace_keyword.ace_operator {color: #8ABEB7}.ace-tomorrow-night .ace_constant.ace_character,.ace-tomorrow-night .ace_constant.ace_language,.ace-tomorrow-night .ace_constant.ace_numeric,.ace-tomorrow-night .ace_keyword.ace_other.ace_unit,.ace-tomorrow-night .ace_support.ace_constant,.ace-tomorrow-night .ace_variable.ace_parameter {color: #DE935F}.ace-tomorrow-night .ace_constant.ace_other {color: #CED1CF}.ace-tomorrow-night .ace_invalid {color: #CED2CF;background-color: #DF5F5F}.ace-tomorrow-night .ace_invalid.ace_deprecated {color: #CED2CF;background-color: #B798BF}.ace-tomorrow-night .ace_fold {background-color: #81A2BE;border-color: #C5C8C6}.ace-tomorrow-night .ace_entity.ace_name.ace_function,.ace-tomorrow-night .ace_support.ace_function,.ace-tomorrow-night .ace_variable {color: #81A2BE}.ace-tomorrow-night .ace_support.ace_class,.ace-tomorrow-night .ace_support.ace_type {color: #F0C674}.ace-tomorrow-night .ace_heading,.ace-tomorrow-night .ace_markup.ace_heading,.ace-tomorrow-night .ace_string {color: #B5BD68}.ace-tomorrow-night .ace_entity.ace_name.ace_tag,.ace-tomorrow-night .ace_entity.ace_other.ace_attribute-name,.ace-tomorrow-night .ace_meta.ace_tag,.ace-tomorrow-night .ace_string.ace_regexp,.ace-tomorrow-night .ace_variable {color: #CC6666}.ace-tomorrow-night .ace_comment {color: #969896}.ace-tomorrow-night .ace_indent-guide {background: url(data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAACCAYAAACZgbYnAAAAEklEQVQImWNgYGBgYHB3d/8PAAOIAdULw8qMAAAAAElFTkSuQmCC) right repeat-y}";var r=e("../lib/dom");r.importCssString(t.cssText,t.cssClass)});                (function() {
+                    ace.require(["ace/theme/tomorrow_night"], function(m) {
+                        if (typeof module == "object" && typeof exports == "object" && module) {
+                            module.exports = m;
+                        }
+                    });
+                })();