test_context.rs

   1use crate::{
   2    Action, AnyView, AnyWindowHandle, App, AppCell, AppContext, AsyncApp, AvailableSpace,
   3    BackgroundExecutor, BorrowAppContext, Bounds, Capslock, ClipboardItem, DrawPhase, Drawable,
   4    Element, Empty, EventEmitter, ForegroundExecutor, Global, InputEvent, Keystroke, Modifiers,
   5    ModifiersChangedEvent, MouseButton, MouseDownEvent, MouseMoveEvent, MouseUpEvent, Pixels,
   6    Platform, Point, Render, Result, Size, Task, TestDispatcher, TestPlatform,
   7    TestScreenCaptureSource, TestWindow, TextSystem, VisualContext, Window, WindowBounds,
   8    WindowHandle, WindowOptions, app::GpuiMode, window::ElementArenaScope,
   9};
  10use anyhow::{anyhow, bail};
  11use futures::{Stream, StreamExt, channel::oneshot};
  12
  13use std::{
  14    cell::RefCell, future::Future, ops::Deref, path::PathBuf, rc::Rc, sync::Arc, time::Duration,
  15};
  16
  17/// A TestAppContext is provided to tests created with `#[gpui::test]`, it provides
  18/// an implementation of `Context` with additional methods that are useful in tests.
  19#[derive(Clone)]
  20pub struct TestAppContext {
  21    #[doc(hidden)]
  22    pub background_executor: BackgroundExecutor,
  23    #[doc(hidden)]
  24    pub foreground_executor: ForegroundExecutor,
  25    #[doc(hidden)]
  26    pub dispatcher: TestDispatcher,
  27    test_platform: Rc<TestPlatform>,
  28    text_system: Arc<TextSystem>,
  29    fn_name: Option<&'static str>,
  30    on_quit: Rc<RefCell<Vec<Box<dyn FnOnce() + 'static>>>>,
  31    #[doc(hidden)]
  32    pub app: Rc<AppCell>,
  33}
  34
  35impl AppContext for TestAppContext {
  36    fn new<T: 'static>(&mut self, build_entity: impl FnOnce(&mut Context<T>) -> T) -> Entity<T> {
  37        let mut app = self.app.borrow_mut();
  38        app.new(build_entity)
  39    }
  40
  41    fn reserve_entity<T: 'static>(&mut self) -> crate::Reservation<T> {
  42        let mut app = self.app.borrow_mut();
  43        app.reserve_entity()
  44    }
  45
  46    fn insert_entity<T: 'static>(
  47        &mut self,
  48        reservation: crate::Reservation<T>,
  49        build_entity: impl FnOnce(&mut Context<T>) -> T,
  50    ) -> Entity<T> {
  51        let mut app = self.app.borrow_mut();
  52        app.insert_entity(reservation, build_entity)
  53    }
  54
  55    fn update_entity<T: 'static, R>(
  56        &mut self,
  57        handle: &Entity<T>,
  58        update: impl FnOnce(&mut T, &mut Context<T>) -> R,
  59    ) -> R {
  60        let mut app = self.app.borrow_mut();
  61        app.update_entity(handle, update)
  62    }
  63
  64    fn as_mut<'a, T>(&'a mut self, _: &Entity<T>) -> super::GpuiBorrow<'a, T>
  65    where
  66        T: 'static,
  67    {
  68        panic!("Cannot use as_mut with a test app context. Try calling update() first")
  69    }
  70
  71    fn read_entity<T, R>(&self, handle: &Entity<T>, read: impl FnOnce(&T, &App) -> R) -> R
  72    where
  73        T: 'static,
  74    {
  75        let app = self.app.borrow();
  76        app.read_entity(handle, read)
  77    }
  78
  79    fn update_window<T, F>(&mut self, window: AnyWindowHandle, f: F) -> Result<T>
  80    where
  81        F: FnOnce(AnyView, &mut Window, &mut App) -> T,
  82    {
  83        let mut lock = self.app.borrow_mut();
  84        lock.update_window(window, f)
  85    }
  86
  87    fn read_window<T, R>(
  88        &self,
  89        window: &WindowHandle<T>,
  90        read: impl FnOnce(Entity<T>, &App) -> R,
  91    ) -> Result<R>
  92    where
  93        T: 'static,
  94    {
  95        let app = self.app.borrow();
  96        app.read_window(window, read)
  97    }
  98
  99    fn background_spawn<R>(&self, future: impl Future<Output = R> + Send + 'static) -> Task<R>
 100    where
 101        R: Send + 'static,
 102    {
 103        self.background_executor.spawn(future)
 104    }
 105
 106    fn read_global<G, R>(&self, callback: impl FnOnce(&G, &App) -> R) -> R
 107    where
 108        G: Global,
 109    {
 110        let app = self.app.borrow();
 111        app.read_global(callback)
 112    }
 113}
 114
 115impl TestAppContext {
 116    /// Creates a new `TestAppContext`. Usually you can rely on `#[gpui::test]` to do this for you.
 117    pub fn build(dispatcher: TestDispatcher, fn_name: Option<&'static str>) -> Self {
 118        let arc_dispatcher = Arc::new(dispatcher.clone());
 119        let background_executor = BackgroundExecutor::new(arc_dispatcher.clone());
 120        let foreground_executor = ForegroundExecutor::new(arc_dispatcher);
 121        let platform = TestPlatform::new(background_executor.clone(), foreground_executor.clone());
 122        let asset_source = Arc::new(());
 123        let http_client = http_client::FakeHttpClient::with_404_response();
 124        let text_system = Arc::new(TextSystem::new(platform.text_system()));
 125
 126        let app = App::new_app(platform.clone(), asset_source, http_client);
 127        app.borrow_mut().mode = GpuiMode::test();
 128
 129        Self {
 130            app,
 131            background_executor,
 132            foreground_executor,
 133            dispatcher,
 134            test_platform: platform,
 135            text_system,
 136            fn_name,
 137            on_quit: Rc::new(RefCell::new(Vec::default())),
 138        }
 139    }
 140
 141    /// Skip all drawing operations for the duration of this test.
 142    pub fn skip_drawing(&mut self) {
 143        self.app.borrow_mut().mode = GpuiMode::Test { skip_drawing: true };
 144    }
 145
 146    /// Create a single TestAppContext, for non-multi-client tests
 147    pub fn single() -> Self {
 148        let dispatcher = TestDispatcher::new(0);
 149        Self::build(dispatcher, None)
 150    }
 151
 152    /// The name of the test function that created this `TestAppContext`
 153    pub fn test_function_name(&self) -> Option<&'static str> {
 154        self.fn_name
 155    }
 156
 157    /// Checks whether there have been any new path prompts received by the platform.
 158    pub fn did_prompt_for_new_path(&self) -> bool {
 159        self.test_platform.did_prompt_for_new_path()
 160    }
 161
 162    /// returns a new `TestAppContext` re-using the same executors to interleave tasks.
 163    pub fn new_app(&self) -> TestAppContext {
 164        Self::build(self.dispatcher.clone(), self.fn_name)
 165    }
 166
 167    /// Called by the test helper to end the test.
 168    /// public so the macro can call it.
 169    pub fn quit(&self) {
 170        self.on_quit.borrow_mut().drain(..).for_each(|f| f());
 171        self.app.borrow_mut().shutdown();
 172    }
 173
 174    /// Register cleanup to run when the test ends.
 175    pub fn on_quit(&mut self, f: impl FnOnce() + 'static) {
 176        self.on_quit.borrow_mut().push(Box::new(f));
 177    }
 178
 179    /// Schedules all windows to be redrawn on the next effect cycle.
 180    pub fn refresh(&mut self) -> Result<()> {
 181        let mut app = self.app.borrow_mut();
 182        app.refresh_windows();
 183        Ok(())
 184    }
 185
 186    /// Returns an executor (for running tasks in the background)
 187    pub fn executor(&self) -> BackgroundExecutor {
 188        self.background_executor.clone()
 189    }
 190
 191    /// Returns an executor (for running tasks on the main thread)
 192    pub fn foreground_executor(&self) -> &ForegroundExecutor {
 193        &self.foreground_executor
 194    }
 195
 196    #[expect(clippy::wrong_self_convention)]
 197    fn new<T: 'static>(&mut self, build_entity: impl FnOnce(&mut Context<T>) -> T) -> Entity<T> {
 198        let mut cx = self.app.borrow_mut();
 199        cx.new(build_entity)
 200    }
 201
 202    /// Gives you an `&mut App` for the duration of the closure
 203    pub fn update<R>(&self, f: impl FnOnce(&mut App) -> R) -> R {
 204        let mut cx = self.app.borrow_mut();
 205        cx.update(f)
 206    }
 207
 208    /// Gives you an `&App` for the duration of the closure
 209    pub fn read<R>(&self, f: impl FnOnce(&App) -> R) -> R {
 210        let cx = self.app.borrow();
 211        f(&cx)
 212    }
 213
 214    /// Adds a new window. The Window will always be backed by a `TestWindow` which
 215    /// can be retrieved with `self.test_window(handle)`
 216    pub fn add_window<F, V>(&mut self, build_window: F) -> WindowHandle<V>
 217    where
 218        F: FnOnce(&mut Window, &mut Context<V>) -> V,
 219        V: 'static + Render,
 220    {
 221        let mut cx = self.app.borrow_mut();
 222
 223        // Some tests rely on the window size matching the bounds of the test display
 224        let bounds = Bounds::maximized(None, &cx);
 225        cx.open_window(
 226            WindowOptions {
 227                window_bounds: Some(WindowBounds::Windowed(bounds)),
 228                ..Default::default()
 229            },
 230            |window, cx| cx.new(|cx| build_window(window, cx)),
 231        )
 232        .unwrap()
 233    }
 234
 235    /// Opens a new window with a specific size.
 236    ///
 237    /// Unlike `add_window` which uses maximized bounds, this allows controlling
 238    /// the window dimensions, which is important for layout-sensitive tests.
 239    pub fn open_window<F, V>(
 240        &mut self,
 241        window_size: Size<Pixels>,
 242        build_window: F,
 243    ) -> WindowHandle<V>
 244    where
 245        F: FnOnce(&mut Window, &mut Context<V>) -> V,
 246        V: 'static + Render,
 247    {
 248        let mut cx = self.app.borrow_mut();
 249        cx.open_window(
 250            WindowOptions {
 251                window_bounds: Some(WindowBounds::Windowed(Bounds {
 252                    origin: Point::default(),
 253                    size: window_size,
 254                })),
 255                ..Default::default()
 256            },
 257            |window, cx| cx.new(|cx| build_window(window, cx)),
 258        )
 259        .unwrap()
 260    }
 261
 262    /// Adds a new window with no content.
 263    pub fn add_empty_window(&mut self) -> &mut VisualTestContext {
 264        let mut cx = self.app.borrow_mut();
 265        let bounds = Bounds::maximized(None, &cx);
 266        let window = cx
 267            .open_window(
 268                WindowOptions {
 269                    window_bounds: Some(WindowBounds::Windowed(bounds)),
 270                    ..Default::default()
 271                },
 272                |_, cx| cx.new(|_| Empty),
 273            )
 274            .unwrap();
 275        drop(cx);
 276        let cx = VisualTestContext::from_window(*window.deref(), self).into_mut();
 277        cx.run_until_parked();
 278        cx
 279    }
 280
 281    /// Adds a new window, and returns its root view and a `VisualTestContext` which can be used
 282    /// as a `Window` and `App` for the rest of the test. Typically you would shadow this context with
 283    /// the returned one. `let (view, cx) = cx.add_window_view(...);`
 284    pub fn add_window_view<F, V>(
 285        &mut self,
 286        build_root_view: F,
 287    ) -> (Entity<V>, &mut VisualTestContext)
 288    where
 289        F: FnOnce(&mut Window, &mut Context<V>) -> V,
 290        V: 'static + Render,
 291    {
 292        let mut cx = self.app.borrow_mut();
 293        let bounds = Bounds::maximized(None, &cx);
 294        let window = cx
 295            .open_window(
 296                WindowOptions {
 297                    window_bounds: Some(WindowBounds::Windowed(bounds)),
 298                    ..Default::default()
 299                },
 300                |window, cx| cx.new(|cx| build_root_view(window, cx)),
 301            )
 302            .unwrap();
 303        drop(cx);
 304        let view = window.root(self).unwrap();
 305        let cx = VisualTestContext::from_window(*window.deref(), self).into_mut();
 306        cx.run_until_parked();
 307
 308        // it might be nice to try and cleanup these at the end of each test.
 309        (view, cx)
 310    }
 311
 312    /// returns the TextSystem
 313    pub fn text_system(&self) -> &Arc<TextSystem> {
 314        &self.text_system
 315    }
 316
 317    /// Simulates writing to the platform clipboard
 318    pub fn write_to_clipboard(&self, item: ClipboardItem) {
 319        self.test_platform.write_to_clipboard(item)
 320    }
 321
 322    /// Simulates reading from the platform clipboard.
 323    /// This will return the most recent value from `write_to_clipboard`.
 324    pub fn read_from_clipboard(&self) -> Option<ClipboardItem> {
 325        self.test_platform.read_from_clipboard()
 326    }
 327
 328    /// Simulates choosing a File in the platform's "Open" dialog.
 329    pub fn simulate_new_path_selection(
 330        &self,
 331        select_path: impl FnOnce(&std::path::Path) -> Option<std::path::PathBuf>,
 332    ) {
 333        self.test_platform.simulate_new_path_selection(select_path);
 334    }
 335
 336    /// Simulates clicking a button in an platform-level alert dialog.
 337    #[track_caller]
 338    pub fn simulate_prompt_answer(&self, button: &str) {
 339        self.test_platform.simulate_prompt_answer(button);
 340    }
 341
 342    /// Returns true if there's an alert dialog open.
 343    pub fn has_pending_prompt(&self) -> bool {
 344        self.test_platform.has_pending_prompt()
 345    }
 346
 347    /// Returns true if there's an alert dialog open.
 348    pub fn pending_prompt(&self) -> Option<(String, String)> {
 349        self.test_platform.pending_prompt()
 350    }
 351
 352    /// All the urls that have been opened with cx.open_url() during this test.
 353    pub fn opened_url(&self) -> Option<String> {
 354        self.test_platform.opened_url.borrow().clone()
 355    }
 356
 357    /// Simulates the user resizing the window to the new size.
 358    pub fn simulate_window_resize(&self, window_handle: AnyWindowHandle, size: Size<Pixels>) {
 359        self.test_window(window_handle).simulate_resize(size);
 360    }
 361
 362    /// Returns true if there's an alert dialog open.
 363    pub fn expect_restart(&self) -> oneshot::Receiver<Option<PathBuf>> {
 364        let (tx, rx) = futures::channel::oneshot::channel();
 365        self.test_platform.expect_restart.borrow_mut().replace(tx);
 366        rx
 367    }
 368
 369    /// Causes the given sources to be returned if the application queries for screen
 370    /// capture sources.
 371    pub fn set_screen_capture_sources(&self, sources: Vec<TestScreenCaptureSource>) {
 372        self.test_platform.set_screen_capture_sources(sources);
 373    }
 374
 375    /// Returns all windows open in the test.
 376    pub fn windows(&self) -> Vec<AnyWindowHandle> {
 377        self.app.borrow().windows()
 378    }
 379
 380    /// Run the given task on the main thread.
 381    #[track_caller]
 382    pub fn spawn<Fut, R>(&self, f: impl FnOnce(AsyncApp) -> Fut) -> Task<R>
 383    where
 384        Fut: Future<Output = R> + 'static,
 385        R: 'static,
 386    {
 387        self.foreground_executor.spawn(f(self.to_async()))
 388    }
 389
 390    /// true if the given global is defined
 391    pub fn has_global<G: Global>(&self) -> bool {
 392        let app = self.app.borrow();
 393        app.has_global::<G>()
 394    }
 395
 396    /// runs the given closure with a reference to the global
 397    /// panics if `has_global` would return false.
 398    pub fn read_global<G: Global, R>(&self, read: impl FnOnce(&G, &App) -> R) -> R {
 399        let app = self.app.borrow();
 400        read(app.global(), &app)
 401    }
 402
 403    /// runs the given closure with a reference to the global (if set)
 404    pub fn try_read_global<G: Global, R>(&self, read: impl FnOnce(&G, &App) -> R) -> Option<R> {
 405        let lock = self.app.borrow();
 406        Some(read(lock.try_global()?, &lock))
 407    }
 408
 409    /// sets the global in this context.
 410    pub fn set_global<G: Global>(&mut self, global: G) {
 411        let mut lock = self.app.borrow_mut();
 412        lock.update(|cx| cx.set_global(global))
 413    }
 414
 415    /// updates the global in this context. (panics if `has_global` would return false)
 416    pub fn update_global<G: Global, R>(&mut self, update: impl FnOnce(&mut G, &mut App) -> R) -> R {
 417        let mut lock = self.app.borrow_mut();
 418        lock.update(|cx| cx.update_global(update))
 419    }
 420
 421    /// Returns an `AsyncApp` which can be used to run tasks that expect to be on a background
 422    /// thread on the current thread in tests.
 423    pub fn to_async(&self) -> AsyncApp {
 424        AsyncApp {
 425            app: Rc::downgrade(&self.app),
 426            background_executor: self.background_executor.clone(),
 427            foreground_executor: self.foreground_executor.clone(),
 428        }
 429    }
 430
 431    /// Wait until there are no more pending tasks.
 432    pub fn run_until_parked(&self) {
 433        self.dispatcher.run_until_parked();
 434    }
 435
 436    /// Simulate dispatching an action to the currently focused node in the window.
 437    pub fn dispatch_action<A>(&mut self, window: AnyWindowHandle, action: A)
 438    where
 439        A: Action,
 440    {
 441        window
 442            .update(self, |_, window, cx| {
 443                window.dispatch_action(action.boxed_clone(), cx)
 444            })
 445            .unwrap();
 446
 447        self.background_executor.run_until_parked()
 448    }
 449
 450    /// simulate_keystrokes takes a space-separated list of keys to type.
 451    /// cx.simulate_keystrokes("cmd-shift-p b k s p enter")
 452    /// in Zed, this will run backspace on the current editor through the command palette.
 453    /// This will also run the background executor until it's parked.
 454    pub fn simulate_keystrokes(&mut self, window: AnyWindowHandle, keystrokes: &str) {
 455        for keystroke in keystrokes
 456            .split(' ')
 457            .map(Keystroke::parse)
 458            .map(Result::unwrap)
 459        {
 460            self.dispatch_keystroke(window, keystroke);
 461        }
 462
 463        self.background_executor.run_until_parked()
 464    }
 465
 466    /// simulate_input takes a string of text to type.
 467    /// cx.simulate_input("abc")
 468    /// will type abc into your current editor
 469    /// This will also run the background executor until it's parked.
 470    pub fn simulate_input(&mut self, window: AnyWindowHandle, input: &str) {
 471        for keystroke in input.split("").map(Keystroke::parse).map(Result::unwrap) {
 472            self.dispatch_keystroke(window, keystroke);
 473        }
 474
 475        self.background_executor.run_until_parked()
 476    }
 477
 478    /// dispatches a single Keystroke (see also `simulate_keystrokes` and `simulate_input`)
 479    pub fn dispatch_keystroke(&mut self, window: AnyWindowHandle, keystroke: Keystroke) {
 480        self.update_window(window, |_, window, cx| {
 481            window.dispatch_keystroke(keystroke, cx)
 482        })
 483        .unwrap();
 484    }
 485
 486    /// Returns the `TestWindow` backing the given handle.
 487    pub(crate) fn test_window(&self, window: AnyWindowHandle) -> TestWindow {
 488        self.app
 489            .borrow_mut()
 490            .windows
 491            .get_mut(window.id)
 492            .unwrap()
 493            .as_deref_mut()
 494            .unwrap()
 495            .platform_window
 496            .as_test()
 497            .unwrap()
 498            .clone()
 499    }
 500
 501    /// Returns a stream of notifications whenever the Entity is updated.
 502    pub fn notifications<T: 'static>(
 503        &mut self,
 504        entity: &Entity<T>,
 505    ) -> impl Stream<Item = ()> + use<T> {
 506        let (tx, rx) = futures::channel::mpsc::unbounded();
 507        self.update(|cx| {
 508            cx.observe(entity, {
 509                let tx = tx.clone();
 510                move |_, _| {
 511                    let _ = tx.unbounded_send(());
 512                }
 513            })
 514            .detach();
 515            cx.observe_release(entity, move |_, _| tx.close_channel())
 516                .detach()
 517        });
 518        rx
 519    }
 520
 521    /// Returns a stream of events emitted by the given Entity.
 522    pub fn events<Evt, T: 'static + EventEmitter<Evt>>(
 523        &mut self,
 524        entity: &Entity<T>,
 525    ) -> futures::channel::mpsc::UnboundedReceiver<Evt>
 526    where
 527        Evt: 'static + Clone,
 528    {
 529        let (tx, rx) = futures::channel::mpsc::unbounded();
 530        entity
 531            .update(self, |_, cx: &mut Context<T>| {
 532                cx.subscribe(entity, move |_entity, _handle, event, _cx| {
 533                    let _ = tx.unbounded_send(event.clone());
 534                })
 535            })
 536            .detach();
 537        rx
 538    }
 539
 540    /// Runs until the given condition becomes true. (Prefer `run_until_parked` if you
 541    /// don't need to jump in at a specific time).
 542    pub async fn condition<T: 'static>(
 543        &mut self,
 544        entity: &Entity<T>,
 545        mut predicate: impl FnMut(&mut T, &mut Context<T>) -> bool,
 546    ) {
 547        let timer = self.executor().timer(Duration::from_secs(3));
 548        let mut notifications = self.notifications(entity);
 549
 550        use futures::FutureExt as _;
 551        use futures_concurrency::future::Race as _;
 552
 553        (
 554            async {
 555                loop {
 556                    if entity.update(self, &mut predicate) {
 557                        return Ok(());
 558                    }
 559
 560                    if notifications.next().await.is_none() {
 561                        bail!("entity dropped")
 562                    }
 563                }
 564            },
 565            timer.map(|_| Err(anyhow!("condition timed out"))),
 566        )
 567            .race()
 568            .await
 569            .unwrap();
 570    }
 571
 572    /// Set a name for this App.
 573    #[cfg(any(test, feature = "test-support"))]
 574    pub fn set_name(&mut self, name: &'static str) {
 575        self.update(|cx| cx.name = Some(name))
 576    }
 577}
 578
 579impl<T: 'static> Entity<T> {
 580    /// Block until the next event is emitted by the entity, then return it.
 581    pub fn next_event<Event>(&self, cx: &mut TestAppContext) -> impl Future<Output = Event>
 582    where
 583        Event: Send + Clone + 'static,
 584        T: EventEmitter<Event>,
 585    {
 586        let (tx, mut rx) = oneshot::channel();
 587        let mut tx = Some(tx);
 588        let subscription = self.update(cx, |_, cx| {
 589            cx.subscribe(self, move |_, _, event, _| {
 590                if let Some(tx) = tx.take() {
 591                    _ = tx.send(event.clone());
 592                }
 593            })
 594        });
 595
 596        async move {
 597            let event = rx.await.expect("no event emitted");
 598            drop(subscription);
 599            event
 600        }
 601    }
 602}
 603
 604impl<V: 'static> Entity<V> {
 605    /// Returns a future that resolves when the view is next updated.
 606    pub fn next_notification(
 607        &self,
 608        advance_clock_by: Duration,
 609        cx: &TestAppContext,
 610    ) -> impl Future<Output = ()> {
 611        use postage::prelude::{Sink as _, Stream as _};
 612
 613        let (mut tx, mut rx) = postage::mpsc::channel(1);
 614        let subscription = cx.app.borrow_mut().observe(self, move |_, _| {
 615            tx.try_send(()).ok();
 616        });
 617
 618        cx.executor().advance_clock(advance_clock_by);
 619
 620        async move {
 621            rx.recv()
 622                .await
 623                .expect("entity dropped while test was waiting for its next notification");
 624            drop(subscription);
 625        }
 626    }
 627}
 628
 629impl<V> Entity<V> {
 630    /// Returns a future that resolves when the condition becomes true.
 631    pub fn condition<Evt>(
 632        &self,
 633        cx: &TestAppContext,
 634        mut predicate: impl FnMut(&V, &App) -> bool,
 635    ) -> impl Future<Output = ()>
 636    where
 637        Evt: 'static,
 638        V: EventEmitter<Evt>,
 639    {
 640        use postage::prelude::{Sink as _, Stream as _};
 641
 642        let (tx, mut rx) = postage::mpsc::channel(1024);
 643
 644        let mut cx = cx.app.borrow_mut();
 645        let subscriptions = (
 646            cx.observe(self, {
 647                let mut tx = tx.clone();
 648                move |_, _| {
 649                    tx.blocking_send(()).ok();
 650                }
 651            }),
 652            cx.subscribe(self, {
 653                let mut tx = tx;
 654                move |_, _: &Evt, _| {
 655                    tx.blocking_send(()).ok();
 656                }
 657            }),
 658        );
 659
 660        let cx = cx.this.upgrade().unwrap();
 661        let handle = self.downgrade();
 662
 663        async move {
 664            loop {
 665                {
 666                    let cx = cx.borrow();
 667                    let cx = &*cx;
 668                    if predicate(
 669                        handle
 670                            .upgrade()
 671                            .expect("view dropped with pending condition")
 672                            .read(cx),
 673                        cx,
 674                    ) {
 675                        break;
 676                    }
 677                }
 678
 679                rx.recv()
 680                    .await
 681                    .expect("view dropped with pending condition");
 682            }
 683            drop(subscriptions);
 684        }
 685    }
 686}
 687
 688use derive_more::{Deref, DerefMut};
 689
 690use super::{Context, Entity};
 691#[derive(Deref, DerefMut, Clone)]
 692/// A VisualTestContext is the test-equivalent of a `Window` and `App`. It allows you to
 693/// run window-specific test code. It can be dereferenced to a `TextAppContext`.
 694pub struct VisualTestContext {
 695    #[deref]
 696    #[deref_mut]
 697    /// cx is the original TestAppContext (you can more easily access this using Deref)
 698    pub cx: TestAppContext,
 699    window: AnyWindowHandle,
 700}
 701
 702impl VisualTestContext {
 703    /// Provides a `Window` and `App` for the duration of the closure.
 704    pub fn update<R>(&mut self, f: impl FnOnce(&mut Window, &mut App) -> R) -> R {
 705        self.cx
 706            .update_window(self.window, |_, window, cx| f(window, cx))
 707            .unwrap()
 708    }
 709
 710    /// Creates a new VisualTestContext. You would typically shadow the passed in
 711    /// TestAppContext with this, as this is typically more useful.
 712    /// `let cx = VisualTestContext::from_window(window, cx);`
 713    pub fn from_window(window: AnyWindowHandle, cx: &TestAppContext) -> Self {
 714        Self {
 715            cx: cx.clone(),
 716            window,
 717        }
 718    }
 719
 720    /// Wait until there are no more pending tasks.
 721    pub fn run_until_parked(&self) {
 722        self.cx.background_executor.run_until_parked();
 723    }
 724
 725    /// Dispatch the action to the currently focused node.
 726    pub fn dispatch_action<A>(&mut self, action: A)
 727    where
 728        A: Action,
 729    {
 730        self.cx.dispatch_action(self.window, action)
 731    }
 732
 733    /// Read the title off the window (set by `Window#set_window_title`)
 734    pub fn window_title(&mut self) -> Option<String> {
 735        self.cx.test_window(self.window).0.lock().title.clone()
 736    }
 737
 738    /// Simulate a sequence of keystrokes `cx.simulate_keystrokes("cmd-p escape")`
 739    /// Automatically runs until parked.
 740    pub fn simulate_keystrokes(&mut self, keystrokes: &str) {
 741        self.cx.simulate_keystrokes(self.window, keystrokes)
 742    }
 743
 744    /// Simulate typing text `cx.simulate_input("hello")`
 745    /// Automatically runs until parked.
 746    pub fn simulate_input(&mut self, input: &str) {
 747        self.cx.simulate_input(self.window, input)
 748    }
 749
 750    /// Simulate a mouse move event to the given point
 751    pub fn simulate_mouse_move(
 752        &mut self,
 753        position: Point<Pixels>,
 754        button: impl Into<Option<MouseButton>>,
 755        modifiers: Modifiers,
 756    ) {
 757        self.simulate_event(MouseMoveEvent {
 758            position,
 759            modifiers,
 760            pressed_button: button.into(),
 761        })
 762    }
 763
 764    /// Simulate a mouse down event to the given point
 765    pub fn simulate_mouse_down(
 766        &mut self,
 767        position: Point<Pixels>,
 768        button: MouseButton,
 769        modifiers: Modifiers,
 770    ) {
 771        self.simulate_event(MouseDownEvent {
 772            position,
 773            modifiers,
 774            button,
 775            click_count: 1,
 776            first_mouse: false,
 777        })
 778    }
 779
 780    /// Simulate a mouse up event to the given point
 781    pub fn simulate_mouse_up(
 782        &mut self,
 783        position: Point<Pixels>,
 784        button: MouseButton,
 785        modifiers: Modifiers,
 786    ) {
 787        self.simulate_event(MouseUpEvent {
 788            position,
 789            modifiers,
 790            button,
 791            click_count: 1,
 792        })
 793    }
 794
 795    /// Simulate a primary mouse click at the given point
 796    pub fn simulate_click(&mut self, position: Point<Pixels>, modifiers: Modifiers) {
 797        self.simulate_event(MouseDownEvent {
 798            position,
 799            modifiers,
 800            button: MouseButton::Left,
 801            click_count: 1,
 802            first_mouse: false,
 803        });
 804        self.simulate_event(MouseUpEvent {
 805            position,
 806            modifiers,
 807            button: MouseButton::Left,
 808            click_count: 1,
 809        });
 810    }
 811
 812    /// Simulate a modifiers changed event
 813    pub fn simulate_modifiers_change(&mut self, modifiers: Modifiers) {
 814        self.simulate_event(ModifiersChangedEvent {
 815            modifiers,
 816            capslock: Capslock { on: false },
 817        })
 818    }
 819
 820    /// Simulate a capslock changed event
 821    pub fn simulate_capslock_change(&mut self, on: bool) {
 822        self.simulate_event(ModifiersChangedEvent {
 823            modifiers: Modifiers::none(),
 824            capslock: Capslock { on },
 825        })
 826    }
 827
 828    /// Simulates the user resizing the window to the new size.
 829    pub fn simulate_resize(&self, size: Size<Pixels>) {
 830        self.simulate_window_resize(self.window, size)
 831    }
 832
 833    /// debug_bounds returns the bounds of the element with the given selector.
 834    pub fn debug_bounds(&mut self, selector: &'static str) -> Option<Bounds<Pixels>> {
 835        self.update(|window, _| window.rendered_frame.debug_bounds.get(selector).copied())
 836    }
 837
 838    /// Draw an element to the window. Useful for simulating events or actions
 839    pub fn draw<E>(
 840        &mut self,
 841        origin: Point<Pixels>,
 842        space: impl Into<Size<AvailableSpace>>,
 843        f: impl FnOnce(&mut Window, &mut App) -> E,
 844    ) -> (E::RequestLayoutState, E::PrepaintState)
 845    where
 846        E: Element,
 847    {
 848        self.update(|window, cx| {
 849            let _arena_scope = ElementArenaScope::enter(&cx.element_arena);
 850
 851            window.invalidator.set_phase(DrawPhase::Prepaint);
 852            let mut element = Drawable::new(f(window, cx));
 853            element.layout_as_root(space.into(), window, cx);
 854            window.with_absolute_element_offset(origin, |window| element.prepaint(window, cx));
 855
 856            window.invalidator.set_phase(DrawPhase::Paint);
 857            let (request_layout_state, prepaint_state) = element.paint(window, cx);
 858
 859            window.invalidator.set_phase(DrawPhase::None);
 860            window.refresh();
 861
 862            drop(element);
 863            cx.element_arena.borrow_mut().clear();
 864
 865            (request_layout_state, prepaint_state)
 866        })
 867    }
 868
 869    /// Simulate an event from the platform, e.g. a ScrollWheelEvent
 870    /// Make sure you've called [VisualTestContext::draw] first!
 871    pub fn simulate_event<E: InputEvent>(&mut self, event: E) {
 872        self.test_window(self.window)
 873            .simulate_input(event.to_platform_input());
 874        self.background_executor.run_until_parked();
 875    }
 876
 877    /// Simulates the user blurring the window.
 878    pub fn deactivate_window(&mut self) {
 879        if Some(self.window) == self.test_platform.active_window() {
 880            self.test_platform.set_active_window(None)
 881        }
 882        self.background_executor.run_until_parked();
 883    }
 884
 885    /// Simulates the user closing the window.
 886    /// Returns true if the window was closed.
 887    pub fn simulate_close(&mut self) -> bool {
 888        let handler = self
 889            .cx
 890            .update_window(self.window, |_, window, _| {
 891                window
 892                    .platform_window
 893                    .as_test()
 894                    .unwrap()
 895                    .0
 896                    .lock()
 897                    .should_close_handler
 898                    .take()
 899            })
 900            .unwrap();
 901        if let Some(mut handler) = handler {
 902            let should_close = handler();
 903            self.cx
 904                .update_window(self.window, |_, window, _| {
 905                    window.platform_window.on_should_close(handler);
 906                })
 907                .unwrap();
 908            should_close
 909        } else {
 910            false
 911        }
 912    }
 913
 914    /// Get an &mut VisualTestContext (which is mostly what you need to pass to other methods).
 915    /// This method internally retains the VisualTestContext until the end of the test.
 916    pub fn into_mut(self) -> &'static mut Self {
 917        let ptr = Box::into_raw(Box::new(self));
 918        // safety: on_quit will be called after the test has finished.
 919        // the executor will ensure that all tasks related to the test have stopped.
 920        // so there is no way for cx to be accessed after on_quit is called.
 921        // todo: This is unsound under stacked borrows (also tree borrows probably?)
 922        // the mutable reference invalidates `ptr` which is later used in the closure
 923        let cx = unsafe { &mut *ptr };
 924        cx.on_quit(move || unsafe {
 925            drop(Box::from_raw(ptr));
 926        });
 927        cx
 928    }
 929}
 930
 931impl AppContext for VisualTestContext {
 932    fn new<T: 'static>(&mut self, build_entity: impl FnOnce(&mut Context<T>) -> T) -> Entity<T> {
 933        self.cx.new(build_entity)
 934    }
 935
 936    fn reserve_entity<T: 'static>(&mut self) -> crate::Reservation<T> {
 937        self.cx.reserve_entity()
 938    }
 939
 940    fn insert_entity<T: 'static>(
 941        &mut self,
 942        reservation: crate::Reservation<T>,
 943        build_entity: impl FnOnce(&mut Context<T>) -> T,
 944    ) -> Entity<T> {
 945        self.cx.insert_entity(reservation, build_entity)
 946    }
 947
 948    fn update_entity<T, R>(
 949        &mut self,
 950        handle: &Entity<T>,
 951        update: impl FnOnce(&mut T, &mut Context<T>) -> R,
 952    ) -> R
 953    where
 954        T: 'static,
 955    {
 956        self.cx.update_entity(handle, update)
 957    }
 958
 959    fn as_mut<'a, T>(&'a mut self, handle: &Entity<T>) -> super::GpuiBorrow<'a, T>
 960    where
 961        T: 'static,
 962    {
 963        self.cx.as_mut(handle)
 964    }
 965
 966    fn read_entity<T, R>(&self, handle: &Entity<T>, read: impl FnOnce(&T, &App) -> R) -> R
 967    where
 968        T: 'static,
 969    {
 970        self.cx.read_entity(handle, read)
 971    }
 972
 973    fn update_window<T, F>(&mut self, window: AnyWindowHandle, f: F) -> Result<T>
 974    where
 975        F: FnOnce(AnyView, &mut Window, &mut App) -> T,
 976    {
 977        self.cx.update_window(window, f)
 978    }
 979
 980    fn read_window<T, R>(
 981        &self,
 982        window: &WindowHandle<T>,
 983        read: impl FnOnce(Entity<T>, &App) -> R,
 984    ) -> Result<R>
 985    where
 986        T: 'static,
 987    {
 988        self.cx.read_window(window, read)
 989    }
 990
 991    fn background_spawn<R>(&self, future: impl Future<Output = R> + Send + 'static) -> Task<R>
 992    where
 993        R: Send + 'static,
 994    {
 995        self.cx.background_spawn(future)
 996    }
 997
 998    fn read_global<G, R>(&self, callback: impl FnOnce(&G, &App) -> R) -> R
 999    where
1000        G: Global,
1001    {
1002        self.cx.read_global(callback)
1003    }
1004}
1005
1006impl VisualContext for VisualTestContext {
1007    type Result<T> = T;
1008
1009    /// Get the underlying window handle underlying this context.
1010    fn window_handle(&self) -> AnyWindowHandle {
1011        self.window
1012    }
1013
1014    fn new_window_entity<T: 'static>(
1015        &mut self,
1016        build_entity: impl FnOnce(&mut Window, &mut Context<T>) -> T,
1017    ) -> Entity<T> {
1018        self.window
1019            .update(&mut self.cx, |_, window, cx| {
1020                cx.new(|cx| build_entity(window, cx))
1021            })
1022            .expect("window was unexpectedly closed")
1023    }
1024
1025    fn update_window_entity<V: 'static, R>(
1026        &mut self,
1027        view: &Entity<V>,
1028        update: impl FnOnce(&mut V, &mut Window, &mut Context<V>) -> R,
1029    ) -> R {
1030        self.window
1031            .update(&mut self.cx, |_, window, cx| {
1032                view.update(cx, |v, cx| update(v, window, cx))
1033            })
1034            .expect("window was unexpectedly closed")
1035    }
1036
1037    fn replace_root_view<V>(
1038        &mut self,
1039        build_view: impl FnOnce(&mut Window, &mut Context<V>) -> V,
1040    ) -> Entity<V>
1041    where
1042        V: 'static + Render,
1043    {
1044        self.window
1045            .update(&mut self.cx, |_, window, cx| {
1046                window.replace_root(cx, build_view)
1047            })
1048            .expect("window was unexpectedly closed")
1049    }
1050
1051    fn focus<V: crate::Focusable>(&mut self, view: &Entity<V>) {
1052        self.window
1053            .update(&mut self.cx, |_, window, cx| {
1054                view.read(cx).focus_handle(cx).focus(window, cx)
1055            })
1056            .expect("window was unexpectedly closed")
1057    }
1058}
1059
1060impl AnyWindowHandle {
1061    /// Creates the given view in this window.
1062    pub fn build_entity<V: Render + 'static>(
1063        &self,
1064        cx: &mut TestAppContext,
1065        build_view: impl FnOnce(&mut Window, &mut Context<V>) -> V,
1066    ) -> Entity<V> {
1067        self.update(cx, |_, window, cx| cx.new(|cx| build_view(window, cx)))
1068            .unwrap()
1069    }
1070}