Merge pull request #2012 from ehuss/bump-version

Update to 0.4.26

.github/ISSUE_TEMPLATE/bug_report.yml

@@ -0,0 +1,45 @@
+name: Bug Report
+description: Create a report to help us improve
+labels: ["C-bug"]
+body:
+  - type: markdown
+    attributes:
+      value: Thanks for filing a 🐛 bug report 😄!
+  - type: textarea
+    id: problem
+    attributes:
+      label: Problem
+      description: >
+        Please provide a clear and concise description of what the bug is,
+        including what currently happens and what you expected to happen.
+    validations:
+      required: true
+  - type: textarea
+    id: steps
+    attributes:
+      label: Steps
+      description: Please list the steps to reproduce the bug.
+      placeholder: |
+        1.
+        2.
+        3.
+  - type: textarea
+    id: possible-solutions
+    attributes:
+      label: Possible Solution(s)
+      description: >
+        Not obligatory, but suggest a fix/reason for the bug,
+        or ideas how to implement the addition or change.
+  - type: textarea
+    id: notes
+    attributes:
+      label: Notes
+      description: Provide any additional notes that might be helpful.
+  - type: textarea
+    id: version
+    attributes:
+      label: Version
+      description: >
+        Please paste the output of running `mdbook --version` or which version
+        of the library you are using.
+      render: text

.github/ISSUE_TEMPLATE/feature_request.yml

@@ -0,0 +1,28 @@
+name: Enhancement
+description: Suggest an idea for enhancing mdBook
+labels: ["C-enhancement"]
+body:
+  - type: markdown
+    attributes:
+      value: |
+        Thanks for filing a 🙋 feature request 😄!
+  - type: textarea
+    id: problem
+    attributes:
+      label: Problem
+      description: >
+        Please provide a clear description of your use case and the problem
+        this feature request is trying to solve.
+    validations:
+      required: true
+  - type: textarea
+    id: solution
+    attributes:
+      label: Proposed Solution
+      description: >
+        Please provide a clear and concise description of what you want to happen.
+  - type: textarea
+    id: notes
+    attributes:
+      label: Notes
+      description: Provide any additional context or information that might be helpful.

.github/ISSUE_TEMPLATE/question.yml

@@ -0,0 +1,24 @@
+name: Question
+description: Have a question on how to use mdBook?
+labels: ["C-question"]
+body:
+  - type: markdown
+    attributes:
+      value: |
+        Got a question on how to do something with mdBook?
+  - type: textarea
+    id: question
+    attributes:
+      label: Question
+      description: >
+        Enter your question here. Please try to provide as much detail as possible.
+    validations:
+      required: true
+  - type: textarea
+    id: version
+    attributes:
+      label: Version
+      description: >
+        Please paste the output of running `mdbook --version` or which version
+        of the library you are using.
+      render: text

.github/workflows/deploy.yml

@@ -17,11 +17,11 @@ jobs:
           - x86_64-pc-windows-msvc
         include:
           - target: aarch64-unknown-linux-musl
-            os: ubuntu-latest
+            os: ubuntu-20.04
           - target: x86_64-unknown-linux-gnu
-            os: ubuntu-latest
+            os: ubuntu-20.04
           - target: x86_64-unknown-linux-musl
-            os: ubuntu-latest
+            os: ubuntu-20.04
           - target: x86_64-apple-darwin
             os: macos-latest
           - target: x86_64-pc-windows-msvc

.github/workflows/main.yml

@@ -30,9 +30,9 @@ jobs:
             os: windows-latest
             rust: stable
           - build: msrv
-            os: ubuntu-latest
-            # sync MSRV with docs: guide/src/guide/installation.md
-            rust: 1.56.0
+            os: ubuntu-20.04
+            # sync MSRV with docs: guide/src/guide/installation.md and Cargo.toml
+            rust: 1.60.0
     steps:
     - uses: actions/checkout@master
     - name: Install Rust

CHANGELOG.md

@@ -1,5 +1,53 @@
 # Changelog
 
+## mdBook 0.4.26
+[v0.4.25...v0.4.26](https://github.com/rust-lang/mdBook/compare/v0.4.25...v0.4.26)
+
+### Changed
+- Removed custom scrollbars for webkit browsers
+  [#1961](https://github.com/rust-lang/mdBook/pull/1961)
+- Updated some dependencies
+  [#1998](https://github.com/rust-lang/mdBook/pull/1998)
+  [#2009](https://github.com/rust-lang/mdBook/pull/2009)
+  [#2011](https://github.com/rust-lang/mdBook/pull/2011)
+- Fonts are now part of the theme.
+  The `output.html.copy-fonts` option has been deprecated.
+  To define custom fonts, be sure to define `theme/fonts.css`.
+  [#1987](https://github.com/rust-lang/mdBook/pull/1987)
+
+### Fixed
+- Fixed overflow viewport issue with mobile Safari
+  [#1994](https://github.com/rust-lang/mdBook/pull/1994)
+
+## mdBook 0.4.25
+[e14d381...1ba74a3](https://github.com/rust-lang/mdBook/compare/e14d381...1ba74a3)
+
+### Fixed
+- Fixed a regression where `mdbook test -L deps path-to-book` would not work.
+  [#1959](https://github.com/rust-lang/mdBook/pull/1959)
+
+## mdBook 0.4.24
+[eb77083...8767ebf](https://github.com/rust-lang/mdBook/compare/eb77083...8767ebf)
+
+### Fixed
+- The precompiled linux-gnu mdbook binary available on [GitHub Releases](https://github.com/rust-lang/mdBook/releases) inadvertently switched to a newer version of glibc. This release goes back to an older version that should be more compatible on older versions of Linux.
+  [#1955](https://github.com/rust-lang/mdBook/pull/1955)
+
+## mdBook 0.4.23
+[678b469...68a75da](https://github.com/rust-lang/mdBook/compare/678b469...68a75da)
+
+### Changed
+- Updated all dependencies
+  [#1951](https://github.com/rust-lang/mdBook/pull/1951)
+  [#1952](https://github.com/rust-lang/mdBook/pull/1952)
+  [#1844](https://github.com/rust-lang/mdBook/pull/1844)
+- Updated minimum Rust version to 1.60.
+  [#1951](https://github.com/rust-lang/mdBook/pull/1951)
+
+### Fixed
+- Fixed a regression where playground code was missing hidden lines, preventing it from compiling correctly.
+  [#1950](https://github.com/rust-lang/mdBook/pull/1950)
+
 ## mdBook 0.4.22
 [40c06f5...4844f72](https://github.com/rust-lang/mdBook/compare/40c06f5...4844f72)
 

CONTRIBUTING.md

@@ -7,13 +7,22 @@ If you have come here to learn how to contribute to mdBook, we have some tips fo
 First of all, don't hesitate to ask questions!
 Use the [issue tracker](https://github.com/rust-lang/mdBook/issues), no question is too simple.
 
+### Issue assignment
+
+**:warning: Important :warning:**
+
+Before working on pull request, please ping us on the corresponding issue.
+The current PR backlog is beyond what we can process at this time.
+Only issues that have an [`E-Help-wanted`](https://github.com/rust-lang/mdBook/labels/E-Help-wanted) or [`Feature accepted`](https://github.com/rust-lang/mdBook/labels/Feature%20accepted) label will likely receive reviews.
+If there isn't already an open issue for what you want to work on, please open one first to see if it is something we would be available to review.
+
 ### Issues to work on
 
-Any issue is up for the grabbing, but if you are starting out, you might be interested in the
+If you are starting out, you might be interested in the
 [E-Easy issues](https://github.com/rust-lang/mdBook/issues?q=is%3Aopen+is%3Aissue+label%3AE-Easy).
 Those are issues that are considered more straightforward for beginners to Rust or the codebase itself.
-These issues can be a good launching pad for more involved issues. Easy tasks for a first time contribution
-include documentation improvements, new tests, examples, updating dependencies, etc.
+These issues can be a good launching pad for more involved issues.
+Easy tasks for a first time contribution include documentation improvements, new tests, examples, updating dependencies, etc.
 
 If you come from a web development background, you might be interested in issues related to web technologies tagged
 [A-JavaScript](https://github.com/rust-lang/mdBook/issues?q=is%3Aopen+is%3Aissue+label%3AA-JavaScript),
@@ -21,16 +30,16 @@ If you come from a web development background, you might be interested in issues
 [A-HTML](https://github.com/rust-lang/mdBook/issues?q=is%3Aopen+is%3Aissue+label%3AA-HTML) or
 [A-Mobile](https://github.com/rust-lang/mdBook/issues?q=is%3Aopen+is%3Aissue+label%3AA-Mobile).
 
-When you decide you want to work on a specific issue, ping us on that issue so that we can assign it to you.
+When you decide you want to work on a specific issue, and it isn't already assigned to someone else, assign the issue to yourself by leaving a comment with the text `@rustbot claim`.
 Again, do not hesitate to ask questions. We will gladly mentor anyone that want to tackle an issue.
 
 Issues on the issue tracker are categorized with the following labels:
 
 - **A**-prefixed labels state which area of the project an issue relates to.
 - **E**-prefixed labels show an estimate of the experience necessary to fix the issue.
-- **M**-prefixed labels are meta-issues used for questions, discussions, or tracking issues
+- **M**-prefixed labels are meta-issues regarding the management of the mdBook project itself
 - **S**-prefixed labels show the status of the issue
-- **T**-prefixed labels show the type of issue
+- **C**-prefixed labels show the category of issue
 
 ### Building mdBook
 
@@ -59,7 +68,7 @@ This will ensure we have good quality source code that is better for us all to m
 [rustfmt](https://github.com/rust-lang/rustfmt) has a lot more information on the project.
 The quick guide is
 
-1. Install it
+1. Install it (`rustfmt` is usually installed by default via [rustup](https://rustup.rs/)):
     ```
     rustup component add rustfmt
     ```
@@ -71,18 +80,15 @@ The quick guide is
    ```
    cargo fmt
    ```
-   When run through `cargo` it will format all bin and lib files in the current crate.
+   When run through `cargo` it will format all bin and lib files in the current package.
 
 For more information, such as running it from your favourite editor, please see the `rustfmt` project. [rustfmt](https://github.com/rust-lang/rustfmt)
 
 
 #### Finding Issues with Clippy
 
-Clippy is a code analyser/linter detecting mistakes, and therefore 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/rust-clippy)
+[Clippy](https://doc.rust-lang.org/clippy/) is a code analyser/linter detecting mistakes, and therefore 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.
 
 1. To install
     ```
@@ -93,17 +99,36 @@ The best documentation can be found over at [rust-clippy](https://github.com/rus
     cargo clippy
     ```
 
-Clippy has an ever growing list of checks, that are managed in [lint files](https://rust-lang.github.io/rust-clippy/master/index.html).
+### Change requirements
+
+Please consider the following when making a change:
+
+* Almost all changes that modify the Rust code must be accompanied with a test.
+
+* Almost all features and changes must update the documentation.
+  mdBook has the [mdBook Guide](https://rust-lang.github.io/mdBook/) whose source is at <https://github.com/rust-lang/mdBook/tree/master/guide>.
+
+* Almost all Rust items should be documented with doc comments.
+  See the [Rustdoc Book](https://doc.rust-lang.org/rustdoc/) for more information on writing doc comments.
+
+* Breaking the API can only be done in major SemVer releases.
+  These are done very infrequently, so it is preferred to avoid these when possible.
+  See [SemVer Compatibility](https://doc.rust-lang.org/cargo/reference/semver.html) for more information on what a SemVer breaking change is.
+
+  (Note: At this time, some SemVer breaking changes are inevitable due to the current code structure.
+  An example is adding new fields to the config structures.
+  These are intended to be fixed in the next major release.)
+
+* Similarly, the CLI interface is considered to be stable.
+  Care should be taken to avoid breaking existing workflows.
+
+* Check out the [Rust API Guidelines](https://rust-lang.github.io/api-guidelines/) for guidelines on designing the API.
 
 ### Making a pull-request
 
 When you feel comfortable that your changes could be integrated into mdBook, you can create a pull-request on GitHub.
 One of the core maintainers will then approve the changes or request some changes before it gets merged.
 
-If you want to make your pull-request even better, you might want to run [Clippy](https://github.com/Manishearth/rust-clippy)
-and [rustfmt](https://github.com/rust-lang/rustfmt) on the code first.
-This is not a requirement though and will never block a pull-request from being merged.
-
 That's it, happy contributions! :tada: :tada: :tada:
 
 ## Browser compatibility and testing

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "mdbook"
-version = "0.4.22"
+version = "0.4.26"
 authors = [
     "Mathieu David <mathieudavid@mathieudavid.org>",
     "Michael-F-Bryan <michaelfbryan@gmail.com>",
@@ -14,14 +14,15 @@ license = "MPL-2.0"
 readme = "README.md"
 repository = "https://github.com/rust-lang/mdBook"
 description = "Creates a book from markdown files"
+rust-version = "1.60"
 
 [dependencies]
 anyhow = "1.0.28"
-chrono = "0.4"
-clap = { version = "3.0", features = ["cargo"] }
-clap_complete = "3.0"
+chrono = { version = "0.4", default-features = false, features = ["clock"] }
+clap = { version = "4.0.29", features = ["cargo", "wrap_help"] }
+clap_complete = "4.0.6"
 once_cell = "1"
-env_logger = "0.9.0"
+env_logger = "0.10.0"
 handlebars = "4.0"
 log = "0.4"
 memchr = "2.0"
@@ -32,11 +33,12 @@ serde = { version = "1.0", features = ["derive"] }
 serde_json = "1.0"
 shlex = "1"
 tempfile = "3.0"
-toml = "0.5.1"
-topological-sort = "0.1.0"
+toml = "0.7.2"
+topological-sort = "0.2.2"
 
 # Watch feature
-notify = { version = "4.0", optional = true }
+notify = { version = "5.0.0", optional = true }
+notify-debouncer-mini = { version = "0.2.1", optional = true }
 gitignore = { version = "1.0", optional = true }
 
 # Serve feature
@@ -49,16 +51,16 @@ elasticlunr-rs = { version = "3.0.0", optional = true }
 ammonia = { version = "3", optional = true }
 
 [dev-dependencies]
-assert_cmd = "1"
+assert_cmd = "2.0.7"
 predicates = "2"
-select = "0.5"
+select = "0.6.0"
 semver = "1.0"
 pretty_assertions = "1.2.1"
 walkdir = "2.0"
 
 [features]
 default = ["watch", "serve", "search"]
-watch = ["notify", "gitignore"]
+watch = ["notify", "notify-debouncer-mini", "gitignore"]
 serve = ["futures-util", "tokio", "warp"]
 search = ["elasticlunr-rs", "ammonia"]
 

examples/nop-preprocessor.rs

@@ -1,5 +1,5 @@
 use crate::nop_lib::Nop;
-use clap::{App, Arg, ArgMatches};
+use clap::{Arg, ArgMatches, Command};
 use mdbook::book::Book;
 use mdbook::errors::Error;
 use mdbook::preprocess::{CmdPreprocessor, Preprocessor, PreprocessorContext};
@@ -7,11 +7,11 @@ use semver::{Version, VersionReq};
 use std::io;
 use std::process;
 
-pub fn make_app() -> App<'static> {
-    App::new("nop-preprocessor")
+pub fn make_app() -> Command {
+    Command::new("nop-preprocessor")
         .about("A mdbook preprocessor which does precisely nothing")
         .subcommand(
-            App::new("supports")
+            Command::new("supports")
                 .arg(Arg::new("renderer").required(true))
                 .about("Check whether a renderer is supported by this preprocessor"),
         )
@@ -54,7 +54,9 @@ fn handle_preprocessing(pre: &dyn Preprocessor) -> Result<(), Error> {
 }
 
 fn handle_supports(pre: &dyn Preprocessor, sub_args: &ArgMatches) -> ! {
-    let renderer = sub_args.value_of("renderer").expect("Required argument");
+    let renderer = sub_args
+        .get_one::<String>("renderer")
+        .expect("Required argument");
     let supported = pre.supports_renderer(renderer);
 
     // Signal whether the renderer is supported by exiting with 1 or 0.

guide/src/continuous-integration.md

@@ -21,7 +21,7 @@ A simple approach would be to use the popular `curl` CLI tool to download the ex
 
 ```sh
 mkdir bin
-curl -sSL https://github.com/rust-lang/mdBook/releases/download/v0.4.22/mdbook-v0.4.22-x86_64-unknown-linux-gnu.tar.gz | tar -xz --directory=bin
+curl -sSL https://github.com/rust-lang/mdBook/releases/download/v0.4.26/mdbook-v0.4.26-x86_64-unknown-linux-gnu.tar.gz | tar -xz --directory=bin
 bin/mdbook build
 ```
 

guide/src/format/configuration/environment-variables.md

@@ -29,7 +29,7 @@ book's title without needing to touch your `book.toml`.
 > building the book with something like
 >
 > ```shell
-> $ export MDBOOK_BOOK="{'title': 'My Awesome Book', authors: ['Michael-F-Bryan']}"
+> $ export MDBOOK_BOOK='{"title": "My Awesome Book", "authors": ["Michael-F-Bryan"]}'
 > $ mdbook build
 > ```
 

guide/src/format/configuration/renderers.md

@@ -126,7 +126,10 @@ The following configuration options are available:
   that occur in code blocks and code spans. Defaults to `false`.
 - **mathjax-support:** Adds support for [MathJax](../mathjax.md). Defaults to
   `false`.
-- **copy-fonts:** Copies fonts.css and respective font files to the output directory and use them in the default theme. Defaults to `true`.
+- **copy-fonts:** (**Deprecated**) If `true` (the default), mdBook uses its built-in fonts which are copied to the output directory.
+  If `false`, the built-in fonts will not be used.
+  This option is deprecated. If you want to define your own custom fonts,
+  create a `theme/fonts/fonts.css` file and store the fonts in the `theme/fonts/` directory.
 - **google-analytics:** This field has been deprecated and will be removed in a future release.
   Use the `theme/head.hbs` file to add the appropriate Google Analytics code instead.
 - **additional-css:** If you need to slightly change the appearance of your book

guide/src/format/theme/README.md

@@ -26,6 +26,8 @@ Here are the files you can override:
 - **_highlight.css_** is the theme used for the code highlighting.
 - **_favicon.svg_** and **_favicon.png_** the favicon that will be used. The SVG
   version is used by [newer browsers].
+- **fonts/fonts.css** contains the definition of which fonts to load.
+  Custom fonts can be included in the `fonts` directory.
 
 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

guide/src/guide/installation.md

@@ -20,7 +20,7 @@ To make it easier to run, put the path to the binary into your `PATH`.
 
 To build the `mdbook` executable from source, you will first need to install Rust and Cargo.
 Follow the instructions on the [Rust installation page].
-mdBook currently requires at least Rust version 1.54.
+mdBook currently requires at least Rust version 1.60.
 
 Once you have installed Rust, the following command can be used to build and install mdBook:
 

src/book/init.rs

@@ -6,6 +6,7 @@ use super::MDBook;
 use crate::config::Config;
 use crate::errors::*;
 use crate::theme;
+use crate::utils::fs::write_file;
 use log::{debug, error, info, trace};
 
 /// A helper for setting up a new book and its directory structure.
@@ -98,7 +99,9 @@ impl BookBuilder {
     fn write_book_toml(&self) -> Result<()> {
         debug!("Writing book.toml");
         let book_toml = self.root.join("book.toml");
-        let cfg = toml::to_vec(&self.config).with_context(|| "Unable to serialize the config")?;
+        let cfg = toml::to_string(&self.config)
+            .with_context(|| "Unable to serialize the config")?
+            .into_bytes();
 
         File::create(book_toml)
             .with_context(|| "Couldn't create book.toml")?
@@ -158,6 +161,19 @@ impl BookBuilder {
         let mut highlight_js = File::create(themedir.join("highlight.js"))?;
         highlight_js.write_all(theme::HIGHLIGHT_JS)?;
 
+        write_file(&themedir.join("fonts"), "fonts.css", theme::fonts::CSS)?;
+        for (file_name, contents) in theme::fonts::LICENSES {
+            write_file(&themedir, file_name, contents)?;
+        }
+        for (file_name, contents) in theme::fonts::OPEN_SANS.iter() {
+            write_file(&themedir, file_name, contents)?;
+        }
+        write_file(
+            &themedir,
+            theme::fonts::SOURCE_CODE_PRO.0,
+            theme::fonts::SOURCE_CODE_PRO.1,
+        )?;
+
         Ok(())
     }
 

src/book/mod.rs

@@ -313,6 +313,7 @@ impl MDBook {
                     }
                 }
 
+                debug!("running {:?}", cmd);
                 let output = cmd.output()?;
 
                 if !output.status.success() {

src/cmd/build.rs

@@ -1,28 +1,16 @@
+use super::command_prelude::*;
 use crate::{get_book_dir, open};
-use clap::{arg, App, Arg, ArgMatches};
 use mdbook::errors::Result;
 use mdbook::MDBook;
+use std::path::PathBuf;
 
 // Create clap subcommand arguments
-pub fn make_subcommand<'help>() -> App<'help> {
-    App::new("build")
+pub fn make_subcommand() -> Command {
+    Command::new("build")
         .about("Builds a book from its markdown files")
-        .arg(
-            Arg::new("dest-dir")
-                .short('d')
-                .long("dest-dir")
-                .value_name("dest-dir")
-                .help(
-                    "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(arg!([dir]
-            "Root directory for the book{n}\
-            (Defaults to the Current Directory when omitted)"
-        ))
-        .arg(arg!(-o --open "Opens the compiled book in a web browser"))
+        .arg_dest_dir()
+        .arg_root_dir()
+        .arg_open()
 }
 
 // Build command implementation
@@ -30,13 +18,13 @@ pub fn execute(args: &ArgMatches) -> Result<()> {
     let book_dir = get_book_dir(args);
     let mut book = MDBook::load(&book_dir)?;
 
-    if let Some(dest_dir) = args.value_of("dest-dir") {
+    if let Some(dest_dir) = args.get_one::<PathBuf>("dest-dir") {
         book.config.build.build_dir = dest_dir.into();
     }
 
     book.build()?;
 
-    if args.is_present("open") {
+    if args.get_flag("open") {
         // FIXME: What's the right behaviour if we don't use the HTML renderer?
         let path = book.build_dir_for("html").join("index.html");
         if !path.exists() {

src/cmd/clean.rs

@@ -1,28 +1,16 @@
+use super::command_prelude::*;
 use crate::get_book_dir;
 use anyhow::Context;
-use clap::{arg, App, Arg, ArgMatches};
 use mdbook::MDBook;
 use std::fs;
+use std::path::PathBuf;
 
 // Create clap subcommand arguments
-pub fn make_subcommand<'help>() -> App<'help> {
-    App::new("clean")
+pub fn make_subcommand() -> Command {
+    Command::new("clean")
         .about("Deletes a built book")
-        .arg(
-            Arg::new("dest-dir")
-                .short('d')
-                .long("dest-dir")
-                .value_name("dest-dir")
-                .help(
-                    "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(arg!([dir]
-            "Root directory for the book{n}\
-            (Defaults to the Current Directory when omitted)"
-        ))
+        .arg_dest_dir()
+        .arg_root_dir()
 }
 
 // Clean command implementation
@@ -30,7 +18,7 @@ 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") {
+    let dir_to_remove = match args.get_one::<PathBuf>("dest-dir") {
         Some(dest_dir) => dest_dir.into(),
         None => book.root.join(&book.config.build.build_dir),
     };

src/cmd/command_prelude.rs

@@ -0,0 +1,45 @@
+//! Helpers for building the command-line arguments for commands.
+
+pub use clap::{arg, Arg, ArgMatches, Command};
+use std::path::PathBuf;
+
+pub trait CommandExt: Sized {
+    fn _arg(self, arg: Arg) -> Self;
+
+    fn arg_dest_dir(self) -> Self {
+        self._arg(
+            Arg::new("dest-dir")
+                .short('d')
+                .long("dest-dir")
+                .value_name("dest-dir")
+                .value_parser(clap::value_parser!(PathBuf))
+                .help(
+                    "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`.",
+                ),
+        )
+    }
+
+    fn arg_root_dir(self) -> Self {
+        self._arg(
+            Arg::new("dir")
+                .help(
+                    "Root directory for the book\n\
+                    (Defaults to the current directory when omitted)",
+                )
+                .value_parser(clap::value_parser!(PathBuf)),
+        )
+    }
+
+    fn arg_open(self) -> Self {
+        self._arg(arg!(-o --open "Opens the compiled book in a web browser"))
+    }
+}
+
+impl CommandExt for Command {
+    fn _arg(self, arg: Arg) -> Self {
+        self.arg(arg)
+    }
+}

src/cmd/init.rs

@@ -1,5 +1,5 @@
 use crate::get_book_dir;
-use clap::{arg, App, Arg, ArgMatches};
+use clap::{arg, ArgMatches, Command as ClapCommand};
 use mdbook::config;
 use mdbook::errors::Result;
 use mdbook::MDBook;
@@ -8,30 +8,22 @@ use std::io::Write;
 use std::process::Command;
 
 // Create clap subcommand arguments
-pub fn make_subcommand<'help>() -> App<'help> {
-    App::new("init")
+pub fn make_subcommand() -> ClapCommand {
+    ClapCommand::new("init")
         .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(arg!([dir]
-            "Directory to create the book in{n}\
-            (Defaults to the Current Directory when omitted)"
-        ))
+        .arg(
+            arg!([dir]
+                "Directory to create the book in\n\
+                (Defaults to the current directory when omitted)"
+            )
+            .value_parser(clap::value_parser!(std::path::PathBuf)),
+        )
         .arg(arg!(--theme "Copies the default theme into your source folder"))
         .arg(arg!(--force "Skips confirmation prompts"))
+        .arg(arg!(--title <title> "Sets the book title"))
         .arg(
-            Arg::new("title")
-                .long("title")
-                .takes_value(true)
-                .help("Sets the book title")
-                .required(false),
-        )
-        .arg(
-            Arg::new("ignore")
-                .long("ignore")
-                .takes_value(true)
-                .possible_values(&["none", "git"])
-                .help("Creates a VCS ignore file (i.e. .gitignore)")
-                .required(false),
+            arg!(--ignore <ignore> "Creates a VCS ignore file (i.e. .gitignore)")
+                .value_parser(["none", "git"]),
         )
 }
 
@@ -41,12 +33,12 @@ pub fn execute(args: &ArgMatches) -> Result<()> {
     let mut builder = MDBook::init(&book_dir);
     let mut config = config::Config::default();
     // If flag `--theme` is present, copy theme to src
-    if args.is_present("theme") {
+    if args.get_flag("theme") {
         let theme_dir = book_dir.join("theme");
         println!();
         println!("Copying the default theme to {}", theme_dir.display());
         // Skip this if `--force` is present
-        if !args.is_present("force") && theme_dir.exists() {
+        if !args.get_flag("force") && theme_dir.exists() {
             println!("This could potentially overwrite files already present in that directory.");
             print!("\nAre you sure you want to continue? (y/n) ");
 
@@ -59,7 +51,7 @@ pub fn execute(args: &ArgMatches) -> Result<()> {
         }
     }
 
-    if let Some(ignore) = args.value_of("ignore") {
+    if let Some(ignore) = args.get_one::<String>("ignore").map(|s| s.as_str()) {
         match ignore {
             "git" => builder.create_gitignore(true),
             _ => builder.create_gitignore(false),
@@ -71,8 +63,8 @@ pub fn execute(args: &ArgMatches) -> Result<()> {
         }
     }
 
-    config.book.title = if args.is_present("title") {
-        args.value_of("title").map(String::from)
+    config.book.title = if args.contains_id("title") {
+        args.get_one::<String>("title").map(String::from)
     } else {
         request_book_title()
     };

src/cmd/mod.rs

@@ -2,6 +2,7 @@
 
 pub mod build;
 pub mod clean;
+pub mod command_prelude;
 pub mod init;
 #[cfg(feature = "serve")]
 pub mod serve;

src/cmd/serve.rs

@@ -1,7 +1,8 @@
+use super::command_prelude::*;
 #[cfg(feature = "watch")]
 use super::watch;
 use crate::{get_book_dir, open};
-use clap::{arg, App, Arg, ArgMatches};
+use clap::builder::NonEmptyStringValueParser;
 use futures_util::sink::SinkExt;
 use futures_util::StreamExt;
 use mdbook::errors::*;
@@ -18,43 +19,30 @@ use warp::Filter;
 const LIVE_RELOAD_ENDPOINT: &str = "__livereload";
 
 // Create clap subcommand arguments
-pub fn make_subcommand<'help>() -> App<'help> {
-    App::new("serve")
+pub fn make_subcommand() -> Command {
+    Command::new("serve")
         .about("Serves a book at http://localhost:3000, and rebuilds it on changes")
-        .arg(
-            Arg::new("dest-dir")
-                .short('d')
-                .long("dest-dir")
-                .value_name("dest-dir")
-                .help(
-                    "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(arg!([dir]
-            "Root directory for the book{n}\
-            (Defaults to the Current Directory when omitted)"
-        ))
+        .arg_dest_dir()
+        .arg_root_dir()
         .arg(
             Arg::new("hostname")
                 .short('n')
                 .long("hostname")
-                .takes_value(true)
+                .num_args(1)
                 .default_value("localhost")
-                .forbid_empty_values(true)
+                .value_parser(NonEmptyStringValueParser::new())
                 .help("Hostname to listen on for HTTP connections"),
         )
         .arg(
             Arg::new("port")
                 .short('p')
                 .long("port")
-                .takes_value(true)
+                .num_args(1)
                 .default_value("3000")
-                .forbid_empty_values(true)
+                .value_parser(NonEmptyStringValueParser::new())
                 .help("Port to use for HTTP connections"),
         )
-        .arg(arg!(-o --open "Opens the compiled book in a web browser"))
+        .arg_open()
 }
 
 // Serve command implementation
@@ -62,17 +50,17 @@ 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 hostname = args.value_of("hostname").unwrap();
-    let open_browser = args.is_present("open");
+    let port = args.get_one::<String>("port").unwrap();
+    let hostname = args.get_one::<String>("hostname").unwrap();
+    let open_browser = args.get_flag("open");
 
     let address = format!("{}:{}", hostname, port);
 
     let update_config = |book: &mut MDBook| {
         book.config
-            .set("output.html.live-reload-endpoint", &LIVE_RELOAD_ENDPOINT)
+            .set("output.html.live-reload-endpoint", LIVE_RELOAD_ENDPOINT)
             .expect("live-reload-endpoint update failed");
-        if let Some(dest_dir) = args.value_of("dest-dir") {
+        if let Some(dest_dir) = args.get_one::<PathBuf>("dest-dir") {
             book.config.build.build_dir = dest_dir.into();
         }
         // Override site-url for local serving of the 404 file

src/cmd/test.rs

@@ -1,63 +1,53 @@
+use super::command_prelude::*;
 use crate::get_book_dir;
-use clap::{arg, App, Arg, ArgMatches};
+use clap::builder::NonEmptyStringValueParser;
+use clap::{Arg, ArgAction, ArgMatches, Command};
 use mdbook::errors::Result;
 use mdbook::MDBook;
+use std::path::PathBuf;
 
 // Create clap subcommand arguments
-pub fn make_subcommand<'help>() -> App<'help> {
-    App::new("test")
+pub fn make_subcommand() -> Command {
+    Command::new("test")
         .about("Tests that a book's Rust code samples compile")
+        // FIXME: --dest-dir is unused by the test command, it should be removed
+        .arg_dest_dir()
+        .arg_root_dir()
         .arg(
-            Arg::new("dest-dir")
-                .short('d')
-                .long("dest-dir")
-                .value_name("dest-dir")
-                .help(
-                    "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(
             Arg::new("chapter")
                 .short('c')
                 .long("chapter")
-                .value_name("chapter")
-                .help(
-                    "Only test the specified chapter{n}\
-                    Where the name of the chapter is defined in the SUMMARY.md file.{n}\
-                    Use the special name \"?\" to the list of chapter names."
-                )
+                .value_name("chapter"),
+        )
+        .arg(
+            Arg::new("library-path")
+                .short('L')
+                .long("library-path")
+                .value_name("dir")
+                .value_delimiter(',')
+                .value_parser(NonEmptyStringValueParser::new())
+                .action(ArgAction::Append)
+                .help(
+                    "A comma-separated list of directories to add to the crate \
+                    search path when building tests",
+                ),
         )
-        .arg(arg!([dir]
-            "Root directory for the book{n}\
-            (Defaults to the Current Directory when omitted)"
-        ))
-        .arg(Arg::new("library-path")
-            .short('L')
-            .long("library-path")
-            .value_name("dir")
-            .takes_value(true)
-            .use_delimiter(true)
-            .require_delimiter(true)
-            .multiple_values(true)
-            .multiple_occurrences(true)
-            .forbid_empty_values(true)
-            .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)
+        .get_many("library-path")
+        .map(|it| it.map(String::as_str).collect())
         .unwrap_or_default();
-    let chapter: Option<&str> = args.value_of("chapter");
+
+    let chapter: Option<&str> = args.get_one::<String>("chapter").map(|s| s.as_str());
 
     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();
+    if let Some(dest_dir) = args.get_one::<PathBuf>("dest-dir") {
+        book.config.build.build_dir = dest_dir.to_path_buf();
     }
     match chapter {
         Some(_) => book.test_chapter(library_paths, chapter),

src/cmd/watch.rs

@@ -1,34 +1,20 @@
+use super::command_prelude::*;
 use crate::{get_book_dir, open};
-use clap::{arg, App, Arg, ArgMatches};
 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<'help>() -> App<'help> {
-    App::new("watch")
+pub fn make_subcommand() -> Command {
+    Command::new("watch")
         .about("Watches a book's files and rebuilds it on changes")
-        .arg(
-            Arg::new("dest-dir")
-                .short('d')
-                .long("dest-dir")
-                .value_name("dest-dir")
-                .help(
-                    "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(arg!([dir]
-            "Root directory for the book{n}\
-            (Defaults to the Current Directory when omitted)"
-        ))
-        .arg(arg!(-o --open "Opens the compiled book in a web browser"))
+        .arg_dest_dir()
+        .arg_root_dir()
+        .arg_open()
 }
 
 // Watch command implementation
@@ -37,13 +23,13 @@ pub fn execute(args: &ArgMatches) -> Result<()> {
     let mut book = MDBook::load(&book_dir)?;
 
     let update_config = |book: &mut MDBook| {
-        if let Some(dest_dir) = args.value_of("dest-dir") {
+        if let Some(dest_dir) = args.get_one::<PathBuf>("dest-dir") {
             book.config.build.build_dir = dest_dir.into();
         }
     };
     update_config(&mut book);
 
-    if args.is_present("open") {
+    if args.get_flag("open") {
         book.build()?;
         let path = book.build_dir_for("html").join("index.html");
         if !path.exists() {
@@ -121,30 +107,31 @@ 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,
+    let mut debouncer = match notify_debouncer_mini::new_debouncer(Duration::from_secs(1), None, tx)
+    {
+        Ok(d) => d,
         Err(e) => {
             error!("Error while trying to watch the files:\n\n\t{:?}", e);
             std::process::exit(1)
         }
     };
+    let watcher = debouncer.watcher();
 
     // Add the source directory to the watcher
-    if let Err(e) = watcher.watch(book.source_dir(), Recursive) {
+    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);
+    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);
+    let _ = watcher.watch(&book.root.join("book.toml"), NonRecursive);
 
     for dir in &book.config.build.extra_watch_dirs {
         let path = dir.canonicalize().unwrap();
@@ -166,16 +153,19 @@ where
 
         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,
+        let paths: Vec<_> = all_events
+            .filter_map(|event| match event {
+                Ok(events) => Some(events),
+                Err(errors) => {
+                    for error in errors {
+                        log::warn!("error while watching for changes: {error}");
+                    }
+                    None
                 }
             })
-            .collect::<Vec<_>>();
+            .flatten()
+            .map(|event| event.path)
+            .collect();
 
         // If we are watching files outside the current repository (via extra-watch-dirs), then they are definitionally
         // ignored by gitignore. So we handle this case by including such files into the watched paths list.

src/main.rs

@@ -5,7 +5,7 @@ extern crate log;
 
 use anyhow::anyhow;
 use chrono::Local;
-use clap::{App, AppSettings, Arg, ArgMatches};
+use clap::{Arg, ArgMatches, Command};
 use clap_complete::Shell;
 use env_logger::Builder;
 use log::LevelFilter;
@@ -13,7 +13,7 @@ use mdbook::utils;
 use std::env;
 use std::ffi::OsStr;
 use std::io::Write;
-use std::path::{Path, PathBuf};
+use std::path::PathBuf;
 
 mod cmd;
 
@@ -22,10 +22,10 @@ const VERSION: &str = concat!("v", crate_version!());
 fn main() {
     init_logger();
 
-    let app = create_clap_app();
+    let command = create_clap_command();
 
-    // Check which subcomamnd the user ran...
-    let res = match app.get_matches().subcommand() {
+    // Check which subcommand the user ran...
+    let res = match command.get_matches().subcommand() {
         Some(("init", sub_matches)) => cmd::init::execute(sub_matches),
         Some(("build", sub_matches)) => cmd::build::execute(sub_matches),
         Some(("clean", sub_matches)) => cmd::clean::execute(sub_matches),
@@ -35,15 +35,13 @@ fn main() {
         Some(("serve", sub_matches)) => cmd::serve::execute(sub_matches),
         Some(("test", sub_matches)) => cmd::test::execute(sub_matches),
         Some(("completions", sub_matches)) => (|| {
-            let shell: Shell = sub_matches
-                .value_of("shell")
-                .ok_or_else(|| anyhow!("Shell name missing."))?
-                .parse()
-                .map_err(|s| anyhow!("Invalid shell: {}", s))?;
+            let shell = sub_matches
+                .get_one::<Shell>("shell")
+                .ok_or_else(|| anyhow!("Shell name missing."))?;
 
-            let mut complete_app = create_clap_app();
+            let mut complete_app = create_clap_command();
             clap_complete::generate(
-                shell,
+                *shell,
                 &mut complete_app,
                 "mdbook",
                 &mut std::io::stdout().lock(),
@@ -61,13 +59,13 @@ fn main() {
 }
 
 /// Create a list of valid arguments and sub-commands
-fn create_clap_app() -> App<'static> {
-    let app = App::new(crate_name!())
+fn create_clap_command() -> Command {
+    let app = Command::new(crate_name!())
         .about(crate_description!())
         .author("Mathieu David <mathieudavid@mathieudavid.org>")
         .version(VERSION)
-        .setting(AppSettings::PropagateVersion)
-        .setting(AppSettings::ArgRequiredElseHelp)
+        .propagate_version(true)
+        .arg_required_else_help(true)
         .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/mdBook",
@@ -77,12 +75,11 @@ fn create_clap_app() -> App<'static> {
         .subcommand(cmd::test::make_subcommand())
         .subcommand(cmd::clean::make_subcommand())
         .subcommand(
-            App::new("completions")
+            Command::new("completions")
                 .about("Generate shell completions for your shell to stdout")
                 .arg(
                     Arg::new("shell")
-                        .takes_value(true)
-                        .possible_values(Shell::possible_values())
+                        .value_parser(clap::value_parser!(Shell))
                         .help("the shell to generate completions for")
                         .value_name("SHELL")
                         .required(true),
@@ -124,11 +121,10 @@ fn init_logger() {
 }
 
 fn get_book_dir(args: &ArgMatches) -> PathBuf {
-    if let Some(dir) = args.value_of("dir") {
+    if let Some(p) = args.get_one::<PathBuf>("dir") {
         // Check if path is relative from current dir, or absolute...
-        let p = Path::new(dir);
         if p.is_relative() {
-            env::current_dir().unwrap().join(dir)
+            env::current_dir().unwrap().join(p)
         } else {
             p.to_path_buf()
         }
@@ -146,5 +142,5 @@ fn open<P: AsRef<OsStr>>(path: P) {
 
 #[test]
 fn verify_app() {
-    create_clap_app().debug_assert();
+    create_clap_command().debug_assert();
 }

src/renderer/html_handlebars/hbs_renderer.rs

@@ -289,6 +289,31 @@ impl HtmlHandlebars {
                 theme::fonts::SOURCE_CODE_PRO.1,
             )?;
         }
+        if let Some(fonts_css) = &theme.fonts_css {
+            if !fonts_css.is_empty() {
+                if html_config.copy_fonts {
+                    warn!(
+                        "output.html.copy_fonts is deprecated.\n\
+                        Set copy_fonts=false and ensure the fonts you want are in \
+                        the `theme/fonts/` directory."
+                    );
+                }
+                write_file(destination, "fonts/fonts.css", &fonts_css)?;
+            }
+        }
+        if !html_config.copy_fonts && theme.fonts_css.is_none() {
+            warn!(
+                "output.html.copy_fonts is deprecated.\n\
+                This book appears to have copy_fonts=false without a fonts.css file.\n\
+                Add an empty `theme/fonts/fonts.css` file to squelch this warning."
+            );
+        }
+        for font_file in &theme.font_files {
+            let contents = fs::read(font_file)?;
+            let filename = font_file.file_name().unwrap();
+            let filename = Path::new("fonts").join(filename);
+            write_file(destination, filename, &contents)?;
+        }
 
         let playground_config = &html_config.playground;
 
@@ -656,7 +681,8 @@ fn make_data(
         data.insert("mathjax_support".to_owned(), json!(true));
     }
 
-    if html_config.copy_fonts {
+    // This `matches!` checks for a non-empty file.
+    if html_config.copy_fonts || matches!(theme.fonts_css.as_deref(), Some([_, ..])) {
         data.insert("copy_fonts".to_owned(), json!(true));
     }
 

src/theme/book.js

@@ -4,12 +4,14 @@
 window.onunload = function () { };
 
 // Global variable, shared between modules
-function playground_text(playground) {
+function playground_text(playground, hidden = true) {
     let code_block = playground.querySelector("code");
 
     if (window.ace && code_block.classList.contains("editable")) {
         let editor = window.ace.edit(code_block);
         return editor.getValue();
+    } else if (hidden) {
+        return code_block.textContent;
     } else {
         return code_block.innerText;
     }
@@ -166,7 +168,6 @@ function playground_text(playground) {
             .filter(function (node) {return node.classList.contains("editable"); })
             .forEach(function (block) { block.classList.remove('language-rust'); });
 
-        Array
         code_nodes
             .filter(function (node) {return !node.classList.contains("editable"); })
             .forEach(function (block) { hljs.highlightBlock(block); });
@@ -600,7 +601,7 @@ function playground_text(playground) {
         text: function (trigger) {
             hideTooltip(trigger);
             let playground = trigger.closest("pre");
-            return playground_text(playground);
+            return playground_text(playground, false);
         }
     });
 

src/theme/css/chrome.css

@@ -2,12 +2,6 @@
 
 @import 'variables.css';
 
-::-webkit-scrollbar {
-    background: var(--bg);
-}
-::-webkit-scrollbar-thumb {
-    background: var(--scrollbar);
-}
 html {
     scrollbar-color: var(--scrollbar) var(--bg);
 }
@@ -18,6 +12,19 @@ a > .hljs {
     color: var(--links);
 }
 
+/*
+    body-container is necessary because mobile browsers don't seem to like
+    overflow-x on the body tag when there is a <meta name="viewport"> tag.
+*/
+#body-container {
+    /*
+        This is used when the sidebar pushes the body content off the side of
+        the screen on small screens. Without it, dragging on mobile Safari
+        will want to reposition the viewport in a weird way.
+    */
+    overflow-x: hidden;
+}
+
 /* Menu Bar */
 
 #menu-bar,

src/theme/index.hbs

@@ -54,6 +54,7 @@
         {{/if}}
     </head>
     <body>
+    <div id="body-container">
         <!-- Provide site root to javascript -->
         <script>
             var path_to_root = "{{ path_to_root }}";
@@ -309,5 +310,6 @@
         {{/if}}
         {{/if}}
 
+    </div>
     </body>
 </html>

src/theme/mod.rs

@@ -9,7 +9,7 @@ pub mod searcher;
 
 use std::fs::File;
 use std::io::Read;
-use std::path::Path;
+use std::path::{Path, PathBuf};
 
 use crate::errors::*;
 use log::warn;
@@ -54,6 +54,8 @@ pub struct Theme {
     pub general_css: Vec<u8>,
     pub print_css: Vec<u8>,
     pub variables_css: Vec<u8>,
+    pub fonts_css: Option<Vec<u8>>,
+    pub font_files: Vec<PathBuf>,
     pub favicon_png: Option<Vec<u8>>,
     pub favicon_svg: Option<Vec<u8>>,
     pub js: Vec<u8>,
@@ -104,7 +106,7 @@ impl Theme {
                 ),
             ];
 
-            let load_with_warn = |filename: &Path, dest| {
+            let load_with_warn = |filename: &Path, dest: &mut Vec<u8>| {
                 if !filename.exists() {
                     // Don't warn if the file doesn't exist.
                     return false;
@@ -121,6 +123,29 @@ impl Theme {
                 load_with_warn(&filename, dest);
             }
 
+            let fonts_dir = theme_dir.join("fonts");
+            if fonts_dir.exists() {
+                let mut fonts_css = Vec::new();
+                if load_with_warn(&fonts_dir.join("fonts.css"), &mut fonts_css) {
+                    theme.fonts_css.replace(fonts_css);
+                }
+                if let Ok(entries) = fonts_dir.read_dir() {
+                    theme.font_files = entries
+                        .filter_map(|entry| {
+                            let entry = entry.ok()?;
+                            if entry.file_name() == "fonts.css" {
+                                None
+                            } else if entry.file_type().ok()?.is_dir() {
+                                log::info!("skipping font directory {:?}", entry.path());
+                                None
+                            } else {
+                                Some(entry.path())
+                            }
+                        })
+                        .collect();
+                }
+            }
+
             // If the user overrides one favicon, but not the other, do not
             // copy the default for the other.
             let favicon_png = &mut theme.favicon_png.as_mut().unwrap();
@@ -153,6 +178,8 @@ impl Default for Theme {
             general_css: GENERAL_CSS.to_owned(),
             print_css: PRINT_CSS.to_owned(),
             variables_css: VARIABLES_CSS.to_owned(),
+            fonts_css: None,
+            font_files: Vec::new(),
             favicon_png: Some(FAVICON_PNG.to_owned()),
             favicon_svg: Some(FAVICON_SVG.to_owned()),
             js: JS.to_owned(),
@@ -209,10 +236,10 @@ mod tests {
             "favicon.png",
             "favicon.svg",
             "css/chrome.css",
-            "css/fonts.css",
             "css/general.css",
             "css/print.css",
             "css/variables.css",
+            "fonts/fonts.css",
             "book.js",
             "highlight.js",
             "tomorrow-night.css",
@@ -223,6 +250,7 @@ mod tests {
 
         let temp = TempFileBuilder::new().prefix("mdbook-").tempdir().unwrap();
         fs::create_dir(temp.path().join("css")).unwrap();
+        fs::create_dir(temp.path().join("fonts")).unwrap();
 
         // "touch" all of the special files so we have empty copies
         for file in &files {
@@ -240,6 +268,8 @@ mod tests {
             general_css: Vec::new(),
             print_css: Vec::new(),
             variables_css: Vec::new(),
+            fonts_css: Some(Vec::new()),
+            font_files: Vec::new(),
             favicon_png: Some(Vec::new()),
             favicon_svg: Some(Vec::new()),
             js: Vec::new(),

tests/init.rs

@@ -1,5 +1,6 @@
 use mdbook::config::Config;
 use mdbook::MDBook;
+use pretty_assertions::assert_eq;
 use std::fs;
 use std::fs::File;
 use std::io::prelude::*;
@@ -121,6 +122,20 @@ fn copy_theme() {
         "css/variables.css",
         "favicon.png",
         "favicon.svg",
+        "fonts/OPEN-SANS-LICENSE.txt",
+        "fonts/SOURCE-CODE-PRO-LICENSE.txt",
+        "fonts/fonts.css",
+        "fonts/open-sans-v17-all-charsets-300.woff2",
+        "fonts/open-sans-v17-all-charsets-300italic.woff2",
+        "fonts/open-sans-v17-all-charsets-600.woff2",
+        "fonts/open-sans-v17-all-charsets-600italic.woff2",
+        "fonts/open-sans-v17-all-charsets-700.woff2",
+        "fonts/open-sans-v17-all-charsets-700italic.woff2",
+        "fonts/open-sans-v17-all-charsets-800.woff2",
+        "fonts/open-sans-v17-all-charsets-800italic.woff2",
+        "fonts/open-sans-v17-all-charsets-italic.woff2",
+        "fonts/open-sans-v17-all-charsets-regular.woff2",
+        "fonts/source-code-pro-v11-all-charsets-500.woff2",
         "highlight.css",
         "highlight.js",
         "index.hbs",

tests/rendered_output.rs

@@ -1,6 +1,3 @@
-#[macro_use]
-extern crate pretty_assertions;
-
 mod dummy_book;
 
 use crate::dummy_book::{assert_contains_strings, assert_doesnt_contain_strings, DummyBook};
@@ -10,6 +7,7 @@ use mdbook::config::Config;
 use mdbook::errors::*;
 use mdbook::utils::fs::write_file;
 use mdbook::MDBook;
+use pretty_assertions::assert_eq;
 use select::document::Document;
 use select::predicate::{Class, Name, Predicate};
 use std::collections::HashMap;
@@ -842,3 +840,111 @@ mod search {
         }
     }
 }
+
+#[test]
+fn custom_fonts() {
+    // Tests to ensure custom fonts are copied as expected.
+    let builtin_fonts = [
+        "OPEN-SANS-LICENSE.txt",
+        "SOURCE-CODE-PRO-LICENSE.txt",
+        "fonts.css",
+        "open-sans-v17-all-charsets-300.woff2",
+        "open-sans-v17-all-charsets-300italic.woff2",
+        "open-sans-v17-all-charsets-600.woff2",
+        "open-sans-v17-all-charsets-600italic.woff2",
+        "open-sans-v17-all-charsets-700.woff2",
+        "open-sans-v17-all-charsets-700italic.woff2",
+        "open-sans-v17-all-charsets-800.woff2",
+        "open-sans-v17-all-charsets-800italic.woff2",
+        "open-sans-v17-all-charsets-italic.woff2",
+        "open-sans-v17-all-charsets-regular.woff2",
+        "source-code-pro-v11-all-charsets-500.woff2",
+    ];
+    let actual_files = |path: &Path| -> Vec<String> {
+        let mut actual: Vec<_> = path
+            .read_dir()
+            .unwrap()
+            .map(|entry| entry.unwrap().file_name().into_string().unwrap())
+            .collect();
+        actual.sort();
+        actual
+    };
+    let has_fonts_css = |path: &Path| -> bool {
+        let contents = fs::read_to_string(path.join("book/index.html")).unwrap();
+        contents.contains("fonts/fonts.css")
+    };
+
+    // No theme:
+    let temp = TempFileBuilder::new().prefix("mdbook").tempdir().unwrap();
+    let p = temp.path();
+    MDBook::init(p).build().unwrap();
+    MDBook::load(p).unwrap().build().unwrap();
+    assert_eq!(actual_files(&p.join("book/fonts")), &builtin_fonts);
+    assert!(has_fonts_css(p));
+
+    // Full theme.
+    let temp = TempFileBuilder::new().prefix("mdbook").tempdir().unwrap();
+    let p = temp.path();
+    MDBook::init(p).copy_theme(true).build().unwrap();
+    assert_eq!(actual_files(&p.join("theme/fonts")), &builtin_fonts);
+    MDBook::load(p).unwrap().build().unwrap();
+    assert_eq!(actual_files(&p.join("book/fonts")), &builtin_fonts);
+    assert!(has_fonts_css(p));
+
+    // Mixed with copy_fonts=true
+    // This should generate a deprecation warning.
+    let temp = TempFileBuilder::new().prefix("mdbook").tempdir().unwrap();
+    let p = temp.path();
+    MDBook::init(p).build().unwrap();
+    write_file(&p.join("theme/fonts"), "fonts.css", b"/*custom*/").unwrap();
+    write_file(&p.join("theme/fonts"), "myfont.woff", b"").unwrap();
+    MDBook::load(p).unwrap().build().unwrap();
+    assert!(has_fonts_css(p));
+    let mut expected = Vec::from(builtin_fonts);
+    expected.push("myfont.woff");
+    expected.sort();
+    assert_eq!(actual_files(&p.join("book/fonts")), expected.as_slice());
+
+    // copy-fonts=false, no theme
+    // This should generate a deprecation warning.
+    let temp = TempFileBuilder::new().prefix("mdbook").tempdir().unwrap();
+    let p = temp.path();
+    MDBook::init(p).build().unwrap();
+    let config = Config::from_str("output.html.copy-fonts = false").unwrap();
+    MDBook::load_with_config(p, config)
+        .unwrap()
+        .build()
+        .unwrap();
+    assert!(!has_fonts_css(p));
+    assert!(!p.join("book/fonts").exists());
+
+    // copy-fonts=false with empty fonts.css
+    let temp = TempFileBuilder::new().prefix("mdbook").tempdir().unwrap();
+    let p = temp.path();
+    MDBook::init(p).build().unwrap();
+    write_file(&p.join("theme/fonts"), "fonts.css", b"").unwrap();
+    let config = Config::from_str("output.html.copy-fonts = false").unwrap();
+    MDBook::load_with_config(p, config)
+        .unwrap()
+        .build()
+        .unwrap();
+    assert!(!has_fonts_css(p));
+    assert!(!p.join("book/fonts").exists());
+
+    // copy-fonts=false with fonts theme
+    let temp = TempFileBuilder::new().prefix("mdbook").tempdir().unwrap();
+    let p = temp.path();
+    MDBook::init(p).build().unwrap();
+    write_file(&p.join("theme/fonts"), "fonts.css", b"/*custom*/").unwrap();
+    write_file(&p.join("theme/fonts"), "myfont.woff", b"").unwrap();
+    let config = Config::from_str("output.html.copy-fonts = false").unwrap();
+    MDBook::load_with_config(p, config)
+        .unwrap()
+        .build()
+        .unwrap();
+    assert!(has_fonts_css(p));
+    assert_eq!(
+        actual_files(&p.join("book/fonts")),
+        &["fonts.css", "myfont.woff"]
+    );
+}

triagebot.toml

@@ -1,12 +1,23 @@
 # This will allow users to self assign, and/or drop assignment
 [assign]
 
+# Allows @rustbot ready, review, author, or blocked
+[shortcut]
 
 [relabel]
 allow-unauthenticated = [
-# For Issue areas
+    # For Issue areas
     "A-*",
-    "E-Help-Wanted",
-    "Bug",
-    "Feature-Request"
-]
+    # Categories
+    "C-*",
+    # Commands
+    "Command-*",
+    # Status
+    "S-*",
+    "regression",
+    "Breaking Change",
+    "msrv-bump",
+]
+
+[autolabel."S-waiting-on-review"]
+new_pr = true