fix memory leak!

examples/regression/Cargo.toml

@@ -1,90 +0,0 @@
-[package]
-name = "regression"
-version = "0.1.0"
-edition = "2021"
-
-[lib]
-crate-type = ["cdylib", "rlib"]
-
-[dependencies]
-axum = { version = "0.8.1", optional = true }
-console_error_panic_hook = "0.1.7"
-console_log = "1.0"
-leptos = { path = "../../leptos", features = ["tracing"] }
-leptos_meta = { path = "../../meta" }
-leptos_axum = { path = "../../integrations/axum", optional = true }
-leptos_router = { path = "../../router" }
-serde = { version = "1.0", features = ["derive"] }
-thiserror = "1.0"
-tokio = { version = "1.39", features = [ "rt-multi-thread", "macros", "time" ], optional = true }
-wasm-bindgen = "0.2.92"
-
-[features]
-hydrate = [
-  "leptos/hydrate",
-]
-ssr = [
-  "dep:axum",
-  "dep:tokio",
-  "leptos/ssr",
-  "leptos_meta/ssr",
-  "dep:leptos_axum",
-  "leptos_router/ssr",
-]
-
-[profile.release]
-panic = "abort"
-
-[profile.wasm-release]
-inherits = "release"
-opt-level = 'z'
-lto = true
-codegen-units = 1
-panic = "abort"
-
-[package.metadata.cargo-all-features]
-denylist = ["axum", "tower", "tower-http", "tokio", "sqlx", "leptos_axum"]
-skip_feature_sets = [["ssr", "hydrate"]]
-
-[package.metadata.leptos]
-# The name used by wasm-bindgen/cargo-leptos for the JS/WASM bundle. Defaults to the crate name
-output-name = "regression"
-# The site root folder is where cargo-leptos generate all output. WARNING: all content of this folder will be erased on a rebuild. Use it in your server setup.
-site-root = "target/site"
-# The site-root relative folder where all compiled output (JS, WASM and CSS) is written
-# Defaults to pkg
-site-pkg-dir = "pkg"
-# The IP and port (ex: 127.0.0.1:3000) where the server serves the content. Use it in your server setup.
-site-addr = "127.0.0.1:3000"
-# The port to use for automatic reload monitoring
-reload-port = 3001
-# [Optional] Command to use when running end2end tests. It will run in the end2end dir.
-#   [Windows] for non-WSL use "npx.cmd playwright test"
-#   This binary name can be checked in Powershell with Get-Command npx
-end2end-cmd = "cargo make test-ui"
-end2end-dir = "e2e"
-#  The browserlist query used for optimizing the CSS.
-browserquery = "defaults"
-# Set by cargo-leptos watch when building with that tool. Controls whether autoreload JS will be included in the head
-watch = false
-# The environment Leptos will run in, usually either "DEV" or "PROD"
-env = "DEV"
-# The features to use when compiling the bin target
-#
-# Optional. Can be over-ridden with the command line parameter --bin-features
-bin-features = ["ssr"]
-
-# If the --no-default-features flag should be used when compiling the bin target
-#
-# Optional. Defaults to false.
-bin-default-features = false
-
-# The features to use when compiling the lib target
-#
-# Optional. Can be over-ridden with the command line parameter --lib-features
-lib-features = ["hydrate"]
-
-# If the --no-default-features flag should be used when compiling the lib target
-#
-# Optional. Defaults to false.
-lib-default-features = false

examples/regression/LICENSE

@@ -1,21 +0,0 @@
-MIT License
-
-Copyright (c) 2025 Leptos
-
-Permission is hereby granted, free of charge, to any person obtaining a copy
-of this software and associated documentation files (the "Software"), to deal
-in the Software without restriction, including without limitation the rights
-to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
-copies of the Software, and to permit persons to whom the Software is
-furnished to do so, subject to the following conditions:
-
-The above copyright notice and this permission notice shall be included in all
-copies or substantial portions of the Software.
-
-THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
-IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
-FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
-AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
-LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
-OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
-SOFTWARE.

examples/regression/Makefile.toml

@@ -1,8 +0,0 @@
-extend = [
-    { path = "../cargo-make/main.toml" },
-    { path = "../cargo-make/cargo-leptos-webdriver-test.toml" },
-]
-
-[env]
-
-CLIENT_PROCESS_NAME = "regression"

examples/regression/README.md

@@ -1,8 +0,0 @@
-# Regression Tests
-
-This example functions as a catch-all for all current and future regression
-test cases that typically happens at integration.
-
-## Quick Start
-
-Run `cargo leptos watch` to run this example.

examples/regression/e2e/Cargo.toml

@@ -1,18 +0,0 @@
-[package]
-name = "regression_e2e"
-version = "0.1.0"
-edition = "2021"
-
-[dev-dependencies]
-anyhow = "1.0"
-async-trait = "0.1.81"
-cucumber = "0.21.1"
-fantoccini = "0.21.1"
-pretty_assertions = "1.4"
-serde_json = "1.0"
-tokio = { version = "1.39", features = ["macros", "rt-multi-thread", "time"] }
-url = "2.5"
-
-[[test]]
-name = "app_suite"
-harness = false    # Allow Cucumber to print output instead of libtest

examples/regression/e2e/Makefile.toml

@@ -1,20 +0,0 @@
-extend = { path = "../../cargo-make/main.toml" }
-
-[tasks.test]
-env = { RUN_AUTOMATICALLY = false }
-condition = { env_true = ["RUN_AUTOMATICALLY"] }
-
-[tasks.ci]
-
-[tasks.test-ui]
-command = "cargo"
-args = [
-  "test",
-  "--test",
-  "app_suite",
-  "--",
-  "--retry",
-  "2",
-  "--fail-fast",
-  "${@}",
-]

examples/regression/e2e/README.md

@@ -1,34 +0,0 @@
-# E2E Testing
-
-This example demonstrates e2e testing with Rust using executable requirements.
-
-## Testing Stack
-
-|    |      Role      |  Description |
-|---|---|---|
-| [Cucumber](https://github.com/cucumber-rs/cucumber/tree/main) | Test Runner | Run [Gherkin](https://cucumber.io/docs/gherkin/reference/) specifications as Rust tests |
-| [Fantoccini](https://github.com/jonhoo/fantoccini/tree/main) | Browser Client | Interact with web pages through WebDriver |
-| [Cargo Leptos](https://github.com/leptos-rs/cargo-leptos) | Build Tool |  Compile example and start the server and end-2-end tests |
-| [chromedriver](https://chromedriver.chromium.org/downloads) | WebDriver | Provide WebDriver for Chrome |
-
-## Testing Organization
-
-Testing is organized around what a user can do and see/not see. Test scenarios are grouped by the **user action** and the **object** of that action. This makes it easier to locate and reason about requirements.
-
-Here is a brief overview of how things fit together.
-
-```bash
-features
-└── {action}_{object}.feature   # Specify test scenarios
-tests
-├── fixtures
-│   ├── action.rs               # Perform a user action (click, type, etc.)
-│   ├── check.rs                # Assert what a user can see/not see
-│   ├── find.rs                 # Query page elements
-│   ├── mod.rs
-│   └── world
-│       ├── action_steps.rs     # Map Gherkin steps to user actions
-│       ├── check_steps.rs      # Map Gherkin steps to user expectations
-│       └── mod.rs
-└── app_suite.rs                # Test main
-```

examples/regression/e2e/features/pr_4091.feature

@@ -1,26 +0,0 @@
-@check_pr_4091
-Feature: Regression from pull request 4091
-
-    Scenario: Signal for testing should work
-        Given I see the app
-        And I can access regression test 4091
-        When I select the link test1
-        Then I see the result is the string Test1
-
-    Scenario: The result returns to empty due to on_cleanup
-        Given I see the app
-        And I can access regression test 4091
-        When I select the following links
-            | test1     |
-            | 4091 Home |
-        Then I see the result is empty
-
-    Scenario: The result does not accumulate due to on_cleanup
-        Given I see the app
-        And I can access regression test 4091
-        When I select the following links
-            | test1     |
-            | 4091 Home |
-            | test1     |
-            | 4091 Home |
-        Then I see the result is empty

examples/regression/e2e/tests/app_suite.rs

@@ -1,30 +0,0 @@
-mod fixtures;
-
-use anyhow::Result;
-use cucumber::World;
-use fixtures::world::AppWorld;
-use std::{ffi::OsStr, fs::read_dir};
-
-#[tokio::main]
-async fn main() -> Result<()> {
-    // Normally the below is done, but it's now gotten to the point of
-    // having a sufficient number of tests where the resource contention
-    // of the concurrently running browsers will cause failures on CI.
-    // AppWorld::cucumber()
-    //     .fail_on_skipped()
-    //     .run_and_exit("./features")
-    //     .await;
-
-    // Mitigate the issue by manually stepping through each feature,
-    // rather than letting cucumber glob them and dispatch all at once.
-    for entry in read_dir("./features")? {
-        let path = entry?.path();
-        if path.extension() == Some(OsStr::new("feature")) {
-            AppWorld::cucumber()
-                .fail_on_skipped()
-                .run_and_exit(path)
-                .await;
-        }
-    }
-    Ok(())
-}

examples/regression/e2e/tests/fixtures/action.rs

@@ -1,17 +0,0 @@
-use super::{find, world::HOST};
-use anyhow::Result;
-use fantoccini::Client;
-use std::result::Result::Ok;
-
-pub async fn goto_path(client: &Client, path: &str) -> Result<()> {
-    let url = format!("{}{}", HOST, path);
-    client.goto(&url).await?;
-
-    Ok(())
-}
-
-pub async fn click_link(client: &Client, text: &str) -> Result<()> {
-    let link = find::link_with_text(&client, &text).await?;
-    link.click().await?;
-    Ok(())
-}

examples/regression/e2e/tests/fixtures/check.rs

@@ -1,13 +0,0 @@
-use crate::fixtures::find;
-use anyhow::{Ok, Result};
-use fantoccini::Client;
-use pretty_assertions::assert_eq;
-
-pub async fn result_text_is(
-    client: &Client,
-    expected_text: &str,
-) -> Result<()> {
-    let actual = find::text_at_id(client, "result").await?;
-    assert_eq!(&actual, expected_text);
-    Ok(())
-}

examples/regression/e2e/tests/fixtures/find.rs

@@ -1,21 +0,0 @@
-use anyhow::{Ok, Result};
-use fantoccini::{elements::Element, Client, Locator};
-
-pub async fn text_at_id(client: &Client, id: &str) -> Result<String> {
-    let element = client
-        .wait()
-        .for_element(Locator::Id(id))
-        .await
-        .expect(format!("no such element with id `{}`", id).as_str());
-    let text = element.text().await?;
-    Ok(text)
-}
-
-pub async fn link_with_text(client: &Client, text: &str) -> Result<Element> {
-    let link = client
-        .wait()
-        .for_element(Locator::LinkText(text))
-        .await
-        .expect(format!("Link not found by `{}`", text).as_str());
-    Ok(link)
-}

examples/regression/e2e/tests/fixtures/mod.rs

@@ -1,4 +0,0 @@
-pub mod action;
-pub mod check;
-pub mod find;
-pub mod world;

examples/regression/e2e/tests/fixtures/world/action_steps.rs

@@ -1,47 +0,0 @@
-use crate::fixtures::{action, world::AppWorld};
-use anyhow::{Ok, Result};
-use cucumber::{gherkin::Step, given, when};
-
-#[given("I see the app")]
-#[when("I open the app")]
-async fn i_open_the_app(world: &mut AppWorld) -> Result<()> {
-    let client = &world.client;
-    action::goto_path(client, "").await?;
-
-    Ok(())
-}
-
-#[given(regex = "^I can access regression test (.*)$")]
-#[when(regex = "^I select the link (.*)$")]
-async fn i_select_the_link(world: &mut AppWorld, text: String) -> Result<()> {
-    let client = &world.client;
-    action::click_link(client, &text).await?;
-
-    Ok(())
-}
-
-#[given(expr = "I select the following links")]
-#[when(expr = "I select the following links")]
-async fn i_select_the_following_links(
-    world: &mut AppWorld,
-    step: &Step,
-) -> Result<()> {
-    let client = &world.client;
-
-    if let Some(table) = step.table.as_ref() {
-        for row in table.rows.iter() {
-            action::click_link(client, &row[0]).await?;
-        }
-    }
-
-    Ok(())
-}
-
-#[given(regex = "^I (refresh|reload) the (browser|page)$")]
-#[when(regex = "^I (refresh|reload) the (browser|page)$")]
-async fn i_refresh_the_browser(world: &mut AppWorld) -> Result<()> {
-    let client = &world.client;
-    client.refresh().await?;
-
-    Ok(())
-}

examples/regression/e2e/tests/fixtures/world/check_steps.rs

@@ -1,22 +0,0 @@
-use crate::fixtures::{check, world::AppWorld};
-use anyhow::{Ok, Result};
-use cucumber::then;
-
-#[then(regex = r"^I see the result is empty$")]
-async fn i_see_the_result_is_empty(
-    world: &mut AppWorld,
-) -> Result<()> {
-    let client = &world.client;
-    check::result_text_is(client, "").await?;
-    Ok(())
-}
-
-#[then(regex = r"^I see the result is the string (.*)$")]
-async fn i_see_the_result_is_the_string(
-    world: &mut AppWorld,
-    text: String,
-) -> Result<()> {
-    let client = &world.client;
-    check::result_text_is(client, &text).await?;
-    Ok(())
-}

examples/regression/e2e/tests/fixtures/world/mod.rs

@@ -1,39 +0,0 @@
-pub mod action_steps;
-pub mod check_steps;
-
-use anyhow::Result;
-use cucumber::World;
-use fantoccini::{
-    error::NewSessionError, wd::Capabilities, Client, ClientBuilder,
-};
-
-pub const HOST: &str = "http://127.0.0.1:3000";
-
-#[derive(Debug, World)]
-#[world(init = Self::new)]
-pub struct AppWorld {
-    pub client: Client,
-}
-
-impl AppWorld {
-    async fn new() -> Result<Self, anyhow::Error> {
-        let webdriver_client = build_client().await?;
-
-        Ok(Self {
-            client: webdriver_client,
-        })
-    }
-}
-
-async fn build_client() -> Result<Client, NewSessionError> {
-    let mut cap = Capabilities::new();
-    let arg = serde_json::from_str("{\"args\": [\"-headless\"]}").unwrap();
-    cap.insert("goog:chromeOptions".to_string(), arg);
-
-    let client = ClientBuilder::native()
-        .capabilities(cap)
-        .connect("http://localhost:4444")
-        .await?;
-
-    Ok(client)
-}

examples/regression/src/app.rs

@@ -1,61 +0,0 @@
-use crate::pr_4091::Routes4091;
-use leptos::prelude::*;
-use leptos_meta::{MetaTags, *};
-use leptos_router::{
-    components::{Route, Router, Routes},
-    path,
-};
-
-pub fn shell(options: LeptosOptions) -> impl IntoView {
-    view! {
-        <!DOCTYPE html>
-        <html lang="en">
-            <head>
-                <meta charset="utf-8"/>
-                <meta name="viewport" content="width=device-width, initial-scale=1"/>
-                <AutoReload options=options.clone()/>
-                <HydrationScripts options/>
-                <MetaTags/>
-            </head>
-            <body>
-                <App/>
-            </body>
-        </html>
-    }
-}
-
-#[component]
-pub fn App() -> impl IntoView {
-    provide_meta_context();
-    let fallback = || view! { "Page not found." }.into_view();
-    view! {
-        <Stylesheet id="leptos" href="/pkg/regression.css"/>
-        <Router>
-            <main>
-                <Routes fallback>
-                    <Route path=path!("") view=HomePage/>
-                    <Routes4091/>
-                </Routes>
-            </main>
-        </Router>
-    }
-}
-
-#[server]
-async fn server_call() -> Result<(), ServerFnError> {
-    tokio::time::sleep(std::time::Duration::from_millis(1)).await;
-    Ok(())
-}
-
-#[component]
-fn HomePage() -> impl IntoView {
-    view! {
-        <Title text="Regression Tests"/>
-        <h1>"Listing of regression tests"</h1>
-        <nav>
-            <ul>
-                <li><a href="/4091/">"4091"</a></li>
-            </ul>
-        </nav>
-    }
-}

examples/regression/src/lib.rs

@@ -1,10 +0,0 @@
-pub mod app;
-mod pr_4091;
-
-#[cfg(feature = "hydrate")]
-#[wasm_bindgen::prelude::wasm_bindgen]
-pub fn hydrate() {
-    use app::*;
-    console_error_panic_hook::set_once();
-    leptos::mount::hydrate_body(App);
-}

examples/regression/src/main.rs

@@ -1,37 +0,0 @@
-#[cfg(feature = "ssr")]
-#[tokio::main]
-async fn main() {
-    use axum::Router;
-    use leptos::prelude::*;
-    use leptos_axum::{generate_route_list, LeptosRoutes};
-    use regression::app::{shell, App};
-
-    let conf = get_configuration(None).unwrap();
-    let addr = conf.leptos_options.site_addr;
-    let leptos_options = conf.leptos_options;
-    // Generate the list of routes in your Leptos App
-    let routes = generate_route_list(App);
-
-    let app = Router::new()
-        .leptos_routes(&leptos_options, routes, {
-            let leptos_options = leptos_options.clone();
-            move || shell(leptos_options.clone())
-        })
-        .fallback(leptos_axum::file_and_error_handler(shell))
-        .with_state(leptos_options);
-
-    // run our app with hyper
-    // `axum::Server` is a re-export of `hyper::Server`
-    println!("listening on http://{}", &addr);
-    let listener = tokio::net::TcpListener::bind(&addr).await.unwrap();
-    axum::serve(listener, app.into_make_service())
-        .await
-        .unwrap();
-}
-
-#[cfg(not(feature = "ssr"))]
-pub fn main() {
-    // no client-side main function
-    // unless we want this to work with e.g., Trunk for pure client-side testing
-    // see lib.rs for hydration function instead
-}

examples/regression/src/pr_4091.rs

@@ -1,67 +0,0 @@
-use leptos::{context::Provider, prelude::*};
-use leptos_router::{
-    components::{ParentRoute, Route, A},
-    nested_router::Outlet,
-    path,
-};
-
-// FIXME This should be a set rather than a naive vec for push and pop, as
-// it may be possible for unexpected token be popped/pushed on multi-level
-// navigation.  For basic naive tests it should be Fine(TM).
-#[derive(Clone)]
-struct Expectations(Vec<&'static str>);
-
-#[component]
-pub fn Routes4091() -> impl leptos_router::MatchNestedRoutes + Clone {
-    view! {
-        <ParentRoute path=path!("4091") view=Container>
-            <Route path=path!("") view=Root/>
-            <Route path=path!("test1") view=Test1/>
-        </ParentRoute>
-    }
-    .into_inner()
-}
-
-#[component]
-fn Container() -> impl IntoView {
-    let rw_signal = RwSignal::new(Expectations(Vec::new()));
-    provide_context(rw_signal);
-
-    view! {
-        <nav>
-            <ul>
-                <li><A href="./">"4091 Home"</A></li>
-                <li><A href="test1">"test1"</A></li>
-            </ul>
-        </nav>
-        <div id="result">{move || {
-            rw_signal.with(|ex| ex.0.iter().fold(String::new(), |a, b| a + b + " "))
-        }}</div>
-        <Provider value=rw_signal>
-            <Outlet/>
-        </Provider>
-    }
-}
-
-#[component]
-fn Root() -> impl IntoView {
-    view! {
-        <div>"This is Root"</div>
-    }
-}
-
-#[component]
-fn Test1() -> impl IntoView {
-    let signal = expect_context::<RwSignal<Expectations>>();
-
-    on_cleanup(move || {
-        signal.update(|ex| {
-            ex.0.pop();
-        });
-    });
-
-    view! {
-        {move || signal.update(|ex| ex.0.push("Test1"))}
-        <div>"This is Test1"</div>
-    }
-}

examples/regression/style/main.scss

@@ -1,3 +0,0 @@
-body {
-    font-family: sans-serif;
-}

leptos/src/form.rs

@@ -111,39 +111,28 @@ where
 
     let on_submit = {
         move |ev: SubmitEvent| {
-            // request_animation_frame here schedules this event handler to run slightly later
-            // this means that this `submit` handler will run *after* any other `submit` handlers
-            // that have been added by the user. this is useful because it means that the user can
-            // add an `on:submit` handler and call `ev.prevent_default()` to prevent the form submission
-            //
-            // without this delay, this handler will always run before the user's handler (which was added
-            // later), which means the user can't prevent the form submission in the same way
-            //
-            // see https://github.com/leptos-rs/leptos/issues/3872
-            request_animation_frame(move || {
-                if ev.default_prevented() {
-                    return;
-                }
+            if ev.default_prevented() {
+                return;
+            }
 
-                ev.prevent_default();
+            ev.prevent_default();
 
-                match ServFn::from_event(&ev) {
-                    Ok(new_input) => {
-                        action.dispatch(new_input);
-                    }
-                    Err(err) => {
-                        crate::logging::error!(
-                            "Error converting form field into server function \
-                             arguments: {err:?}"
-                        );
-                        value.set(Some(Err(ServerFnErrorErr::Serialization(
-                            err.to_string(),
-                        )
-                        .into_app_error())));
-                        version.update(|n| *n += 1);
-                    }
+            match ServFn::from_event(&ev) {
+                Ok(new_input) => {
+                    action.dispatch(new_input);
                 }
-            });
+                Err(err) => {
+                    crate::logging::error!(
+                        "Error converting form field into server function \
+                         arguments: {err:?}"
+                    );
+                    value.set(Some(Err(ServerFnErrorErr::Serialization(
+                        err.to_string(),
+                    )
+                    .into_app_error())));
+                    version.update(|n| *n += 1);
+                }
+            }
         }
     };
 

reactive_graph/src/owner.rs

@@ -167,6 +167,7 @@ impl Owner {
                     .map(|parent| parent.read().or_poisoned().arena.clone())
                     .unwrap_or_default(),
                 paused: false,
+                joined_owners: Vec::new(),
             })),
             #[cfg(feature = "hydration")]
             shared_context,
@@ -201,6 +202,7 @@ impl Owner {
                 #[cfg(feature = "sandboxed-arenas")]
                 arena: Default::default(),
                 paused: false,
+                joined_owners: Vec::new(),
             })),
             #[cfg(feature = "hydration")]
             shared_context,
@@ -226,6 +228,7 @@ impl Owner {
                 #[cfg(feature = "sandboxed-arenas")]
                 arena,
                 paused,
+                joined_owners: Vec::new(),
             })),
             #[cfg(feature = "hydration")]
             shared_context: self.shared_context.clone(),
@@ -461,6 +464,7 @@ pub(crate) struct OwnerInner {
     #[cfg(feature = "sandboxed-arenas")]
     arena: Arc<RwLock<ArenaMap>>,
     paused: bool,
+    joined_owners: Vec<WeakOwner>,
 }
 
 impl Debug for OwnerInner {

reactive_graph/src/owner/context.rs

@@ -6,6 +6,15 @@ use std::{
 };
 
 impl Owner {
+    #[doc(hidden)]
+    pub fn join_contexts(&self, other: &Owner) {
+        self.inner
+            .write()
+            .or_poisoned()
+            .joined_owners
+            .push(other.downgrade());
+    }
+
     fn provide_context<T: Send + Sync + 'static>(&self, value: T) {
         self.inner
             .write()
@@ -25,18 +34,27 @@ impl Owner {
         if let Some(context) = contexts.remove(&ty) {
             context.downcast::<T>().ok().map(|n| *n)
         } else {
-            let mut parent = inner.parent.as_ref().and_then(|p| p.upgrade());
-            while let Some(ref this_parent) = parent.clone() {
-                let mut this_parent = this_parent.write().or_poisoned();
-                let contexts = &mut this_parent.contexts;
-                let value = contexts.remove(&ty);
-                let downcast =
-                    value.and_then(|context| context.downcast::<T>().ok());
-                if let Some(value) = downcast {
-                    return Some(*value);
-                } else {
-                    parent =
-                        this_parent.parent.as_ref().and_then(|p| p.upgrade());
+            let parent = inner.parent.as_ref().and_then(|p| p.upgrade());
+            let joined = inner
+                .joined_owners
+                .iter()
+                .flat_map(|owner| owner.upgrade().map(|owner| owner.inner));
+            for parent in parent.into_iter().chain(joined) {
+                let mut parent = Some(parent);
+                while let Some(ref this_parent) = parent.clone() {
+                    let mut this_parent = this_parent.write().or_poisoned();
+                    let contexts = &mut this_parent.contexts;
+                    let value = contexts.remove(&ty);
+                    let downcast =
+                        value.and_then(|context| context.downcast::<T>().ok());
+                    if let Some(value) = downcast {
+                        return Some(*value);
+                    } else {
+                        parent = this_parent
+                            .parent
+                            .as_ref()
+                            .and_then(|p| p.upgrade());
+                    }
                 }
             }
             None
@@ -53,21 +71,29 @@ impl Owner {
         let reference = if let Some(context) = contexts.get(&ty) {
             context.downcast_ref::<T>()
         } else {
-            let mut parent = inner.parent.as_ref().and_then(|p| p.upgrade());
-            while let Some(ref this_parent) = parent.clone() {
-                let this_parent = this_parent.read().or_poisoned();
-                let contexts = &this_parent.contexts;
-                let value = contexts.get(&ty);
-                let downcast =
-                    value.and_then(|context| context.downcast_ref::<T>());
-                if let Some(value) = downcast {
-                    return Some(cb(value));
-                } else {
-                    parent =
-                        this_parent.parent.as_ref().and_then(|p| p.upgrade());
+            let parent = inner.parent.as_ref().and_then(|p| p.upgrade());
+            let joined = inner
+                .joined_owners
+                .iter()
+                .flat_map(|owner| owner.upgrade().map(|owner| owner.inner));
+            for parent in parent.into_iter().chain(joined) {
+                let mut parent = Some(parent);
+                while let Some(ref this_parent) = parent.clone() {
+                    let this_parent = this_parent.read().or_poisoned();
+                    let contexts = &this_parent.contexts;
+                    let value = contexts.get(&ty);
+                    let downcast =
+                        value.and_then(|context| context.downcast_ref::<T>());
+                    if let Some(value) = downcast {
+                        return Some(cb(value));
+                    } else {
+                        parent = this_parent
+                            .parent
+                            .as_ref()
+                            .and_then(|p| p.upgrade());
+                    }
                 }
             }
-
             None
         };
         reference.map(cb)
@@ -83,18 +109,27 @@ impl Owner {
         let reference = if let Some(context) = contexts.get_mut(&ty) {
             context.downcast_mut::<T>()
         } else {
-            let mut parent = inner.parent.as_ref().and_then(|p| p.upgrade());
-            while let Some(ref this_parent) = parent.clone() {
-                let mut this_parent = this_parent.write().or_poisoned();
-                let contexts = &mut this_parent.contexts;
-                let value = contexts.get_mut(&ty);
-                let downcast =
-                    value.and_then(|context| context.downcast_mut::<T>());
-                if let Some(value) = downcast {
-                    return Some(cb(value));
-                } else {
-                    parent =
-                        this_parent.parent.as_ref().and_then(|p| p.upgrade());
+            let parent = inner.parent.as_ref().and_then(|p| p.upgrade());
+            let joined = inner
+                .joined_owners
+                .iter()
+                .flat_map(|owner| owner.upgrade().map(|owner| owner.inner));
+            for parent in parent.into_iter().chain(joined) {
+                let mut parent = Some(parent);
+                while let Some(ref this_parent) = parent.clone() {
+                    let mut this_parent = this_parent.write().or_poisoned();
+                    let contexts = &mut this_parent.contexts;
+                    let value = contexts.get_mut(&ty);
+                    let downcast =
+                        value.and_then(|context| context.downcast_mut::<T>());
+                    if let Some(value) = downcast {
+                        return Some(cb(value));
+                    } else {
+                        parent = this_parent
+                            .parent
+                            .as_ref()
+                            .and_then(|p| p.upgrade());
+                    }
                 }
             }
             None