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,
   9};
  10use anyhow::{anyhow, bail};
  11use futures::{Stream, StreamExt, channel::oneshot};
  12use rand::{SeedableRng, rngs::StdRng};
  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 app: Rc<AppCell>,
  23    #[doc(hidden)]
  24    pub background_executor: BackgroundExecutor,
  25    #[doc(hidden)]
  26    pub foreground_executor: ForegroundExecutor,
  27    #[doc(hidden)]
  28    pub dispatcher: TestDispatcher,
  29    test_platform: Rc<TestPlatform>,
  30    text_system: Arc<TextSystem>,
  31    fn_name: Option<&'static str>,
  32    on_quit: Rc<RefCell<Vec<Box<dyn FnOnce() + 'static>>>>,
  33}
  34
  35impl AppContext for TestAppContext {
  36    type Result<T> = T;
  37
  38    fn new<T: 'static>(
  39        &mut self,
  40        build_entity: impl FnOnce(&mut Context<T>) -> T,
  41    ) -> Self::Result<Entity<T>> {
  42        let mut app = self.app.borrow_mut();
  43        app.new(build_entity)
  44    }
  45
  46    fn reserve_entity<T: 'static>(&mut self) -> Self::Result<crate::Reservation<T>> {
  47        let mut app = self.app.borrow_mut();
  48        app.reserve_entity()
  49    }
  50
  51    fn insert_entity<T: 'static>(
  52        &mut self,
  53        reservation: crate::Reservation<T>,
  54        build_entity: impl FnOnce(&mut Context<T>) -> T,
  55    ) -> Self::Result<Entity<T>> {
  56        let mut app = self.app.borrow_mut();
  57        app.insert_entity(reservation, build_entity)
  58    }
  59
  60    fn update_entity<T: 'static, R>(
  61        &mut self,
  62        handle: &Entity<T>,
  63        update: impl FnOnce(&mut T, &mut Context<T>) -> R,
  64    ) -> Self::Result<R> {
  65        let mut app = self.app.borrow_mut();
  66        app.update_entity(handle, update)
  67    }
  68
  69    fn as_mut<'a, T>(&'a mut self, _: &Entity<T>) -> Self::Result<super::GpuiBorrow<'a, T>>
  70    where
  71        T: 'static,
  72    {
  73        panic!("Cannot use as_mut with a test app context. Try calling update() first")
  74    }
  75
  76    fn read_entity<T, R>(
  77        &self,
  78        handle: &Entity<T>,
  79        read: impl FnOnce(&T, &App) -> R,
  80    ) -> Self::Result<R>
  81    where
  82        T: 'static,
  83    {
  84        let app = self.app.borrow();
  85        app.read_entity(handle, read)
  86    }
  87
  88    fn update_window<T, F>(&mut self, window: AnyWindowHandle, f: F) -> Result<T>
  89    where
  90        F: FnOnce(AnyView, &mut Window, &mut App) -> T,
  91    {
  92        let mut lock = self.app.borrow_mut();
  93        lock.update_window(window, f)
  94    }
  95
  96    fn read_window<T, R>(
  97        &self,
  98        window: &WindowHandle<T>,
  99        read: impl FnOnce(Entity<T>, &App) -> R,
 100    ) -> Result<R>
 101    where
 102        T: 'static,
 103    {
 104        let app = self.app.borrow();
 105        app.read_window(window, read)
 106    }
 107
 108    fn background_spawn<R>(&self, future: impl Future<Output = R> + Send + 'static) -> Task<R>
 109    where
 110        R: Send + 'static,
 111    {
 112        self.background_executor.spawn(future)
 113    }
 114
 115    fn read_global<G, R>(&self, callback: impl FnOnce(&G, &App) -> R) -> Self::Result<R>
 116    where
 117        G: Global,
 118    {
 119        let app = self.app.borrow();
 120        app.read_global(callback)
 121    }
 122}
 123
 124impl TestAppContext {
 125    /// Creates a new `TestAppContext`. Usually you can rely on `#[gpui::test]` to do this for you.
 126    pub fn build(dispatcher: TestDispatcher, fn_name: Option<&'static str>) -> Self {
 127        let arc_dispatcher = Arc::new(dispatcher.clone());
 128        let background_executor = BackgroundExecutor::new(arc_dispatcher.clone());
 129        let foreground_executor = ForegroundExecutor::new(arc_dispatcher);
 130        let platform = TestPlatform::new(background_executor.clone(), foreground_executor.clone());
 131        let asset_source = Arc::new(());
 132        let http_client = http_client::FakeHttpClient::with_404_response();
 133        let text_system = Arc::new(TextSystem::new(platform.text_system()));
 134
 135        let mut app = App::new_app(platform.clone(), asset_source, http_client);
 136        app.borrow_mut().mode = GpuiMode::test();
 137
 138        Self {
 139            app,
 140            background_executor,
 141            foreground_executor,
 142            dispatcher,
 143            test_platform: platform,
 144            text_system,
 145            fn_name,
 146            on_quit: Rc::new(RefCell::new(Vec::default())),
 147        }
 148    }
 149
 150    /// Skip all drawing operations for the duration of this test.
 151    pub fn skip_drawing(&mut self) {
 152        self.app.borrow_mut().mode = GpuiMode::Test { skip_drawing: true };
 153    }
 154
 155    /// Create a single TestAppContext, for non-multi-client tests
 156    pub fn single() -> Self {
 157        let dispatcher = TestDispatcher::new(StdRng::seed_from_u64(0));
 158        Self::build(dispatcher, None)
 159    }
 160
 161    /// The name of the test function that created this `TestAppContext`
 162    pub fn test_function_name(&self) -> Option<&'static str> {
 163        self.fn_name
 164    }
 165
 166    /// Checks whether there have been any new path prompts received by the platform.
 167    pub fn did_prompt_for_new_path(&self) -> bool {
 168        self.test_platform.did_prompt_for_new_path()
 169    }
 170
 171    /// returns a new `TestAppContext` re-using the same executors to interleave tasks.
 172    pub fn new_app(&self) -> TestAppContext {
 173        Self::build(self.dispatcher.clone(), self.fn_name)
 174    }
 175
 176    /// Called by the test helper to end the test.
 177    /// public so the macro can call it.
 178    pub fn quit(&self) {
 179        self.on_quit.borrow_mut().drain(..).for_each(|f| f());
 180        self.app.borrow_mut().shutdown();
 181    }
 182
 183    /// Register cleanup to run when the test ends.
 184    pub fn on_quit(&mut self, f: impl FnOnce() + 'static) {
 185        self.on_quit.borrow_mut().push(Box::new(f));
 186    }
 187
 188    /// Schedules all windows to be redrawn on the next effect cycle.
 189    pub fn refresh(&mut self) -> Result<()> {
 190        let mut app = self.app.borrow_mut();
 191        app.refresh_windows();
 192        Ok(())
 193    }
 194
 195    /// Returns an executor (for running tasks in the background)
 196    pub fn executor(&self) -> BackgroundExecutor {
 197        self.background_executor.clone()
 198    }
 199
 200    /// Returns an executor (for running tasks on the main thread)
 201    pub fn foreground_executor(&self) -> &ForegroundExecutor {
 202        &self.foreground_executor
 203    }
 204
 205    #[expect(clippy::wrong_self_convention)]
 206    fn new<T: 'static>(&mut self, build_entity: impl FnOnce(&mut Context<T>) -> T) -> Entity<T> {
 207        let mut cx = self.app.borrow_mut();
 208        cx.new(build_entity)
 209    }
 210
 211    /// Gives you an `&mut App` for the duration of the closure
 212    pub fn update<R>(&self, f: impl FnOnce(&mut App) -> R) -> R {
 213        let mut cx = self.app.borrow_mut();
 214        cx.update(f)
 215    }
 216
 217    /// Gives you an `&App` for the duration of the closure
 218    pub fn read<R>(&self, f: impl FnOnce(&App) -> R) -> R {
 219        let cx = self.app.borrow();
 220        f(&cx)
 221    }
 222
 223    /// Adds a new window. The Window will always be backed by a `TestWindow` which
 224    /// can be retrieved with `self.test_window(handle)`
 225    pub fn add_window<F, V>(&mut self, build_window: F) -> WindowHandle<V>
 226    where
 227        F: FnOnce(&mut Window, &mut Context<V>) -> V,
 228        V: 'static + Render,
 229    {
 230        let mut cx = self.app.borrow_mut();
 231
 232        // Some tests rely on the window size matching the bounds of the test display
 233        let bounds = Bounds::maximized(None, &cx);
 234        cx.open_window(
 235            WindowOptions {
 236                window_bounds: Some(WindowBounds::Windowed(bounds)),
 237                ..Default::default()
 238            },
 239            |window, cx| cx.new(|cx| build_window(window, cx)),
 240        )
 241        .unwrap()
 242    }
 243
 244    /// Adds a new window with no content.
 245    pub fn add_empty_window(&mut self) -> &mut VisualTestContext {
 246        let mut cx = self.app.borrow_mut();
 247        let bounds = Bounds::maximized(None, &cx);
 248        let window = cx
 249            .open_window(
 250                WindowOptions {
 251                    window_bounds: Some(WindowBounds::Windowed(bounds)),
 252                    ..Default::default()
 253                },
 254                |_, cx| cx.new(|_| Empty),
 255            )
 256            .unwrap();
 257        drop(cx);
 258        let cx = VisualTestContext::from_window(*window.deref(), self).into_mut();
 259        cx.run_until_parked();
 260        cx
 261    }
 262
 263    /// Adds a new window, and returns its root view and a `VisualTestContext` which can be used
 264    /// as a `Window` and `App` for the rest of the test. Typically you would shadow this context with
 265    /// the returned one. `let (view, cx) = cx.add_window_view(...);`
 266    pub fn add_window_view<F, V>(
 267        &mut self,
 268        build_root_view: F,
 269    ) -> (Entity<V>, &mut VisualTestContext)
 270    where
 271        F: FnOnce(&mut Window, &mut Context<V>) -> V,
 272        V: 'static + Render,
 273    {
 274        let mut cx = self.app.borrow_mut();
 275        let bounds = Bounds::maximized(None, &cx);
 276        let window = cx
 277            .open_window(
 278                WindowOptions {
 279                    window_bounds: Some(WindowBounds::Windowed(bounds)),
 280                    ..Default::default()
 281                },
 282                |window, cx| cx.new(|cx| build_root_view(window, cx)),
 283            )
 284            .unwrap();
 285        drop(cx);
 286        let view = window.root(self).unwrap();
 287        let cx = VisualTestContext::from_window(*window.deref(), self).into_mut();
 288        cx.run_until_parked();
 289
 290        // it might be nice to try and cleanup these at the end of each test.
 291        (view, cx)
 292    }
 293
 294    /// returns the TextSystem
 295    pub fn text_system(&self) -> &Arc<TextSystem> {
 296        &self.text_system
 297    }
 298
 299    /// Simulates writing to the platform clipboard
 300    pub fn write_to_clipboard(&self, item: ClipboardItem) {
 301        self.test_platform.write_to_clipboard(item)
 302    }
 303
 304    /// Simulates reading from the platform clipboard.
 305    /// This will return the most recent value from `write_to_clipboard`.
 306    pub fn read_from_clipboard(&self) -> Option<ClipboardItem> {
 307        self.test_platform.read_from_clipboard()
 308    }
 309
 310    /// Simulates choosing a File in the platform's "Open" dialog.
 311    pub fn simulate_new_path_selection(
 312        &self,
 313        select_path: impl FnOnce(&std::path::Path) -> Option<std::path::PathBuf>,
 314    ) {
 315        self.test_platform.simulate_new_path_selection(select_path);
 316    }
 317
 318    /// Simulates clicking a button in an platform-level alert dialog.
 319    #[track_caller]
 320    pub fn simulate_prompt_answer(&self, button: &str) {
 321        self.test_platform.simulate_prompt_answer(button);
 322    }
 323
 324    /// Returns true if there's an alert dialog open.
 325    pub fn has_pending_prompt(&self) -> bool {
 326        self.test_platform.has_pending_prompt()
 327    }
 328
 329    /// Returns true if there's an alert dialog open.
 330    pub fn pending_prompt(&self) -> Option<(String, String)> {
 331        self.test_platform.pending_prompt()
 332    }
 333
 334    /// All the urls that have been opened with cx.open_url() during this test.
 335    pub fn opened_url(&self) -> Option<String> {
 336        self.test_platform.opened_url.borrow().clone()
 337    }
 338
 339    /// Simulates the user resizing the window to the new size.
 340    pub fn simulate_window_resize(&self, window_handle: AnyWindowHandle, size: Size<Pixels>) {
 341        self.test_window(window_handle).simulate_resize(size);
 342    }
 343
 344    /// Returns true if there's an alert dialog open.
 345    pub fn expect_restart(&self) -> oneshot::Receiver<Option<PathBuf>> {
 346        let (tx, rx) = futures::channel::oneshot::channel();
 347        self.test_platform.expect_restart.borrow_mut().replace(tx);
 348        rx
 349    }
 350
 351    /// Causes the given sources to be returned if the application queries for screen
 352    /// capture sources.
 353    pub fn set_screen_capture_sources(&self, sources: Vec<TestScreenCaptureSource>) {
 354        self.test_platform.set_screen_capture_sources(sources);
 355    }
 356
 357    /// Returns all windows open in the test.
 358    pub fn windows(&self) -> Vec<AnyWindowHandle> {
 359        self.app.borrow().windows()
 360    }
 361
 362    /// Run the given task on the main thread.
 363    #[track_caller]
 364    pub fn spawn<Fut, R>(&self, f: impl FnOnce(AsyncApp) -> Fut) -> Task<R>
 365    where
 366        Fut: Future<Output = R> + 'static,
 367        R: 'static,
 368    {
 369        self.foreground_executor.spawn(f(self.to_async()))
 370    }
 371
 372    /// true if the given global is defined
 373    pub fn has_global<G: Global>(&self) -> bool {
 374        let app = self.app.borrow();
 375        app.has_global::<G>()
 376    }
 377
 378    /// runs the given closure with a reference to the global
 379    /// panics if `has_global` would return false.
 380    pub fn read_global<G: Global, R>(&self, read: impl FnOnce(&G, &App) -> R) -> R {
 381        let app = self.app.borrow();
 382        read(app.global(), &app)
 383    }
 384
 385    /// runs the given closure with a reference to the global (if set)
 386    pub fn try_read_global<G: Global, R>(&self, read: impl FnOnce(&G, &App) -> R) -> Option<R> {
 387        let lock = self.app.borrow();
 388        Some(read(lock.try_global()?, &lock))
 389    }
 390
 391    /// sets the global in this context.
 392    pub fn set_global<G: Global>(&mut self, global: G) {
 393        let mut lock = self.app.borrow_mut();
 394        lock.update(|cx| cx.set_global(global))
 395    }
 396
 397    /// updates the global in this context. (panics if `has_global` would return false)
 398    pub fn update_global<G: Global, R>(&mut self, update: impl FnOnce(&mut G, &mut App) -> R) -> R {
 399        let mut lock = self.app.borrow_mut();
 400        lock.update(|cx| cx.update_global(update))
 401    }
 402
 403    /// Returns an `AsyncApp` which can be used to run tasks that expect to be on a background
 404    /// thread on the current thread in tests.
 405    pub fn to_async(&self) -> AsyncApp {
 406        AsyncApp {
 407            app: Rc::downgrade(&self.app),
 408            background_executor: self.background_executor.clone(),
 409            foreground_executor: self.foreground_executor.clone(),
 410        }
 411    }
 412
 413    /// Wait until there are no more pending tasks.
 414    pub fn run_until_parked(&mut self) {
 415        self.background_executor.run_until_parked()
 416    }
 417
 418    /// Simulate dispatching an action to the currently focused node in the window.
 419    pub fn dispatch_action<A>(&mut self, window: AnyWindowHandle, action: A)
 420    where
 421        A: Action,
 422    {
 423        window
 424            .update(self, |_, window, cx| {
 425                window.dispatch_action(action.boxed_clone(), cx)
 426            })
 427            .unwrap();
 428
 429        self.background_executor.run_until_parked()
 430    }
 431
 432    /// simulate_keystrokes takes a space-separated list of keys to type.
 433    /// cx.simulate_keystrokes("cmd-shift-p b k s p enter")
 434    /// in Zed, this will run backspace on the current editor through the command palette.
 435    /// This will also run the background executor until it's parked.
 436    pub fn simulate_keystrokes(&mut self, window: AnyWindowHandle, keystrokes: &str) {
 437        for keystroke in keystrokes
 438            .split(' ')
 439            .map(Keystroke::parse)
 440            .map(Result::unwrap)
 441        {
 442            self.dispatch_keystroke(window, keystroke);
 443        }
 444
 445        self.background_executor.run_until_parked()
 446    }
 447
 448    /// simulate_input takes a string of text to type.
 449    /// cx.simulate_input("abc")
 450    /// will type abc into your current editor
 451    /// This will also run the background executor until it's parked.
 452    pub fn simulate_input(&mut self, window: AnyWindowHandle, input: &str) {
 453        for keystroke in input.split("").map(Keystroke::parse).map(Result::unwrap) {
 454            self.dispatch_keystroke(window, keystroke);
 455        }
 456
 457        self.background_executor.run_until_parked()
 458    }
 459
 460    /// dispatches a single Keystroke (see also `simulate_keystrokes` and `simulate_input`)
 461    pub fn dispatch_keystroke(&mut self, window: AnyWindowHandle, keystroke: Keystroke) {
 462        self.update_window(window, |_, window, cx| {
 463            window.dispatch_keystroke(keystroke, cx)
 464        })
 465        .unwrap();
 466    }
 467
 468    /// Returns the `TestWindow` backing the given handle.
 469    pub(crate) fn test_window(&self, window: AnyWindowHandle) -> TestWindow {
 470        self.app
 471            .borrow_mut()
 472            .windows
 473            .get_mut(window.id)
 474            .unwrap()
 475            .as_deref_mut()
 476            .unwrap()
 477            .platform_window
 478            .as_test()
 479            .unwrap()
 480            .clone()
 481    }
 482
 483    /// Returns a stream of notifications whenever the Entity is updated.
 484    pub fn notifications<T: 'static>(
 485        &mut self,
 486        entity: &Entity<T>,
 487    ) -> impl Stream<Item = ()> + use<T> {
 488        let (tx, rx) = futures::channel::mpsc::unbounded();
 489        self.update(|cx| {
 490            cx.observe(entity, {
 491                let tx = tx.clone();
 492                move |_, _| {
 493                    let _ = tx.unbounded_send(());
 494                }
 495            })
 496            .detach();
 497            cx.observe_release(entity, move |_, _| tx.close_channel())
 498                .detach()
 499        });
 500        rx
 501    }
 502
 503    /// Returns a stream of events emitted by the given Entity.
 504    pub fn events<Evt, T: 'static + EventEmitter<Evt>>(
 505        &mut self,
 506        entity: &Entity<T>,
 507    ) -> futures::channel::mpsc::UnboundedReceiver<Evt>
 508    where
 509        Evt: 'static + Clone,
 510    {
 511        let (tx, rx) = futures::channel::mpsc::unbounded();
 512        entity
 513            .update(self, |_, cx: &mut Context<T>| {
 514                cx.subscribe(entity, move |_entity, _handle, event, _cx| {
 515                    let _ = tx.unbounded_send(event.clone());
 516                })
 517            })
 518            .detach();
 519        rx
 520    }
 521
 522    /// Runs until the given condition becomes true. (Prefer `run_until_parked` if you
 523    /// don't need to jump in at a specific time).
 524    pub async fn condition<T: 'static>(
 525        &mut self,
 526        entity: &Entity<T>,
 527        mut predicate: impl FnMut(&mut T, &mut Context<T>) -> bool,
 528    ) {
 529        let timer = self.executor().timer(Duration::from_secs(3));
 530        let mut notifications = self.notifications(entity);
 531
 532        use futures::FutureExt as _;
 533        use smol::future::FutureExt as _;
 534
 535        async {
 536            loop {
 537                if entity.update(self, &mut predicate) {
 538                    return Ok(());
 539                }
 540
 541                if notifications.next().await.is_none() {
 542                    bail!("entity dropped")
 543                }
 544            }
 545        }
 546        .race(timer.map(|_| Err(anyhow!("condition timed out"))))
 547        .await
 548        .unwrap();
 549    }
 550
 551    /// Set a name for this App.
 552    #[cfg(any(test, feature = "test-support"))]
 553    pub fn set_name(&mut self, name: &'static str) {
 554        self.update(|cx| cx.name = Some(name))
 555    }
 556}
 557
 558impl<T: 'static> Entity<T> {
 559    /// Block until the next event is emitted by the entity, then return it.
 560    pub fn next_event<Event>(&self, cx: &mut TestAppContext) -> impl Future<Output = Event>
 561    where
 562        Event: Send + Clone + 'static,
 563        T: EventEmitter<Event>,
 564    {
 565        let (tx, mut rx) = oneshot::channel();
 566        let mut tx = Some(tx);
 567        let subscription = self.update(cx, |_, cx| {
 568            cx.subscribe(self, move |_, _, event, _| {
 569                if let Some(tx) = tx.take() {
 570                    _ = tx.send(event.clone());
 571                }
 572            })
 573        });
 574
 575        async move {
 576            let event = rx.await.expect("no event emitted");
 577            drop(subscription);
 578            event
 579        }
 580    }
 581}
 582
 583impl<V: 'static> Entity<V> {
 584    /// Returns a future that resolves when the view is next updated.
 585    pub fn next_notification(
 586        &self,
 587        advance_clock_by: Duration,
 588        cx: &TestAppContext,
 589    ) -> impl Future<Output = ()> {
 590        use postage::prelude::{Sink as _, Stream as _};
 591
 592        let (mut tx, mut rx) = postage::mpsc::channel(1);
 593        let subscription = cx.app.borrow_mut().observe(self, move |_, _| {
 594            tx.try_send(()).ok();
 595        });
 596
 597        let duration = if std::env::var("CI").is_ok() {
 598            Duration::from_secs(5)
 599        } else {
 600            Duration::from_secs(1)
 601        };
 602
 603        cx.executor().advance_clock(advance_clock_by);
 604
 605        async move {
 606            let notification = crate::util::smol_timeout(duration, rx.recv())
 607                .await
 608                .expect("next notification timed out");
 609            drop(subscription);
 610            notification.expect("entity dropped while test was waiting for its next notification")
 611        }
 612    }
 613}
 614
 615impl<V> Entity<V> {
 616    /// Returns a future that resolves when the condition becomes true.
 617    pub fn condition<Evt>(
 618        &self,
 619        cx: &TestAppContext,
 620        mut predicate: impl FnMut(&V, &App) -> bool,
 621    ) -> impl Future<Output = ()>
 622    where
 623        Evt: 'static,
 624        V: EventEmitter<Evt>,
 625    {
 626        use postage::prelude::{Sink as _, Stream as _};
 627
 628        let (tx, mut rx) = postage::mpsc::channel(1024);
 629
 630        let mut cx = cx.app.borrow_mut();
 631        let subscriptions = (
 632            cx.observe(self, {
 633                let mut tx = tx.clone();
 634                move |_, _| {
 635                    tx.blocking_send(()).ok();
 636                }
 637            }),
 638            cx.subscribe(self, {
 639                let mut tx = tx;
 640                move |_, _: &Evt, _| {
 641                    tx.blocking_send(()).ok();
 642                }
 643            }),
 644        );
 645
 646        let cx = cx.this.upgrade().unwrap();
 647        let handle = self.downgrade();
 648
 649        async move {
 650            crate::util::smol_timeout(Duration::from_secs(1), async move {
 651                loop {
 652                    {
 653                        let cx = cx.borrow();
 654                        let cx = &*cx;
 655                        if predicate(
 656                            handle
 657                                .upgrade()
 658                                .expect("view dropped with pending condition")
 659                                .read(cx),
 660                            cx,
 661                        ) {
 662                            break;
 663                        }
 664                    }
 665
 666                    cx.borrow().background_executor().start_waiting();
 667                    rx.recv()
 668                        .await
 669                        .expect("view dropped with pending condition");
 670                    cx.borrow().background_executor().finish_waiting();
 671                }
 672            })
 673            .await
 674            .expect("condition timed out");
 675            drop(subscriptions);
 676        }
 677    }
 678}
 679
 680use derive_more::{Deref, DerefMut};
 681
 682use super::{Context, Entity};
 683#[derive(Deref, DerefMut, Clone)]
 684/// A VisualTestContext is the test-equivalent of a `Window` and `App`. It allows you to
 685/// run window-specific test code. It can be dereferenced to a `TextAppContext`.
 686pub struct VisualTestContext {
 687    #[deref]
 688    #[deref_mut]
 689    /// cx is the original TestAppContext (you can more easily access this using Deref)
 690    pub cx: TestAppContext,
 691    window: AnyWindowHandle,
 692}
 693
 694impl VisualTestContext {
 695    /// Provides a `Window` and `App` for the duration of the closure.
 696    pub fn update<R>(&mut self, f: impl FnOnce(&mut Window, &mut App) -> R) -> R {
 697        self.cx
 698            .update_window(self.window, |_, window, cx| f(window, cx))
 699            .unwrap()
 700    }
 701
 702    /// Creates a new VisualTestContext. You would typically shadow the passed in
 703    /// TestAppContext with this, as this is typically more useful.
 704    /// `let cx = VisualTestContext::from_window(window, cx);`
 705    pub fn from_window(window: AnyWindowHandle, cx: &TestAppContext) -> Self {
 706        Self {
 707            cx: cx.clone(),
 708            window,
 709        }
 710    }
 711
 712    /// Wait until there are no more pending tasks.
 713    pub fn run_until_parked(&self) {
 714        self.cx.background_executor.run_until_parked();
 715    }
 716
 717    /// Dispatch the action to the currently focused node.
 718    pub fn dispatch_action<A>(&mut self, action: A)
 719    where
 720        A: Action,
 721    {
 722        self.cx.dispatch_action(self.window, action)
 723    }
 724
 725    /// Read the title off the window (set by `Window#set_window_title`)
 726    pub fn window_title(&mut self) -> Option<String> {
 727        self.cx.test_window(self.window).0.lock().title.clone()
 728    }
 729
 730    /// Simulate a sequence of keystrokes `cx.simulate_keystrokes("cmd-p escape")`
 731    /// Automatically runs until parked.
 732    pub fn simulate_keystrokes(&mut self, keystrokes: &str) {
 733        self.cx.simulate_keystrokes(self.window, keystrokes)
 734    }
 735
 736    /// Simulate typing text `cx.simulate_input("hello")`
 737    /// Automatically runs until parked.
 738    pub fn simulate_input(&mut self, input: &str) {
 739        self.cx.simulate_input(self.window, input)
 740    }
 741
 742    /// Simulate a mouse move event to the given point
 743    pub fn simulate_mouse_move(
 744        &mut self,
 745        position: Point<Pixels>,
 746        button: impl Into<Option<MouseButton>>,
 747        modifiers: Modifiers,
 748    ) {
 749        self.simulate_event(MouseMoveEvent {
 750            position,
 751            modifiers,
 752            pressed_button: button.into(),
 753        })
 754    }
 755
 756    /// Simulate a mouse down event to the given point
 757    pub fn simulate_mouse_down(
 758        &mut self,
 759        position: Point<Pixels>,
 760        button: MouseButton,
 761        modifiers: Modifiers,
 762    ) {
 763        self.simulate_event(MouseDownEvent {
 764            position,
 765            modifiers,
 766            button,
 767            click_count: 1,
 768            first_mouse: false,
 769        })
 770    }
 771
 772    /// Simulate a mouse up event to the given point
 773    pub fn simulate_mouse_up(
 774        &mut self,
 775        position: Point<Pixels>,
 776        button: MouseButton,
 777        modifiers: Modifiers,
 778    ) {
 779        self.simulate_event(MouseUpEvent {
 780            position,
 781            modifiers,
 782            button,
 783            click_count: 1,
 784        })
 785    }
 786
 787    /// Simulate a primary mouse click at the given point
 788    pub fn simulate_click(&mut self, position: Point<Pixels>, modifiers: Modifiers) {
 789        self.simulate_event(MouseDownEvent {
 790            position,
 791            modifiers,
 792            button: MouseButton::Left,
 793            click_count: 1,
 794            first_mouse: false,
 795        });
 796        self.simulate_event(MouseUpEvent {
 797            position,
 798            modifiers,
 799            button: MouseButton::Left,
 800            click_count: 1,
 801        });
 802    }
 803
 804    /// Simulate a modifiers changed event
 805    pub fn simulate_modifiers_change(&mut self, modifiers: Modifiers) {
 806        self.simulate_event(ModifiersChangedEvent {
 807            modifiers,
 808            capslock: Capslock { on: false },
 809        })
 810    }
 811
 812    /// Simulate a capslock changed event
 813    pub fn simulate_capslock_change(&mut self, on: bool) {
 814        self.simulate_event(ModifiersChangedEvent {
 815            modifiers: Modifiers::none(),
 816            capslock: Capslock { on },
 817        })
 818    }
 819
 820    /// Simulates the user resizing the window to the new size.
 821    pub fn simulate_resize(&self, size: Size<Pixels>) {
 822        self.simulate_window_resize(self.window, size)
 823    }
 824
 825    /// debug_bounds returns the bounds of the element with the given selector.
 826    pub fn debug_bounds(&mut self, selector: &'static str) -> Option<Bounds<Pixels>> {
 827        self.update(|window, _| window.rendered_frame.debug_bounds.get(selector).copied())
 828    }
 829
 830    /// Draw an element to the window. Useful for simulating events or actions
 831    pub fn draw<E>(
 832        &mut self,
 833        origin: Point<Pixels>,
 834        space: impl Into<Size<AvailableSpace>>,
 835        f: impl FnOnce(&mut Window, &mut App) -> E,
 836    ) -> (E::RequestLayoutState, E::PrepaintState)
 837    where
 838        E: Element,
 839    {
 840        self.update(|window, cx| {
 841            window.invalidator.set_phase(DrawPhase::Prepaint);
 842            let mut element = Drawable::new(f(window, cx));
 843            element.layout_as_root(space.into(), window, cx);
 844            window.with_absolute_element_offset(origin, |window| element.prepaint(window, cx));
 845
 846            window.invalidator.set_phase(DrawPhase::Paint);
 847            let (request_layout_state, prepaint_state) = element.paint(window, cx);
 848
 849            window.invalidator.set_phase(DrawPhase::None);
 850            window.refresh();
 851
 852            (request_layout_state, prepaint_state)
 853        })
 854    }
 855
 856    /// Simulate an event from the platform, e.g. a ScrollWheelEvent
 857    /// Make sure you've called [VisualTestContext::draw] first!
 858    pub fn simulate_event<E: InputEvent>(&mut self, event: E) {
 859        self.test_window(self.window)
 860            .simulate_input(event.to_platform_input());
 861        self.background_executor.run_until_parked();
 862    }
 863
 864    /// Simulates the user blurring the window.
 865    pub fn deactivate_window(&mut self) {
 866        if Some(self.window) == self.test_platform.active_window() {
 867            self.test_platform.set_active_window(None)
 868        }
 869        self.background_executor.run_until_parked();
 870    }
 871
 872    /// Simulates the user closing the window.
 873    /// Returns true if the window was closed.
 874    pub fn simulate_close(&mut self) -> bool {
 875        let handler = self
 876            .cx
 877            .update_window(self.window, |_, window, _| {
 878                window
 879                    .platform_window
 880                    .as_test()
 881                    .unwrap()
 882                    .0
 883                    .lock()
 884                    .should_close_handler
 885                    .take()
 886            })
 887            .unwrap();
 888        if let Some(mut handler) = handler {
 889            let should_close = handler();
 890            self.cx
 891                .update_window(self.window, |_, window, _| {
 892                    window.platform_window.on_should_close(handler);
 893                })
 894                .unwrap();
 895            should_close
 896        } else {
 897            false
 898        }
 899    }
 900
 901    /// Get an &mut VisualTestContext (which is mostly what you need to pass to other methods).
 902    /// This method internally retains the VisualTestContext until the end of the test.
 903    pub fn into_mut(self) -> &'static mut Self {
 904        let ptr = Box::into_raw(Box::new(self));
 905        // safety: on_quit will be called after the test has finished.
 906        // the executor will ensure that all tasks related to the test have stopped.
 907        // so there is no way for cx to be accessed after on_quit is called.
 908        // todo: This is unsound under stacked borrows (also tree borrows probably?)
 909        // the mutable reference invalidates `ptr` which is later used in the closure
 910        let cx = unsafe { &mut *ptr };
 911        cx.on_quit(move || unsafe {
 912            drop(Box::from_raw(ptr));
 913        });
 914        cx
 915    }
 916}
 917
 918impl AppContext for VisualTestContext {
 919    type Result<T> = <TestAppContext as AppContext>::Result<T>;
 920
 921    fn new<T: 'static>(
 922        &mut self,
 923        build_entity: impl FnOnce(&mut Context<T>) -> T,
 924    ) -> Self::Result<Entity<T>> {
 925        self.cx.new(build_entity)
 926    }
 927
 928    fn reserve_entity<T: 'static>(&mut self) -> Self::Result<crate::Reservation<T>> {
 929        self.cx.reserve_entity()
 930    }
 931
 932    fn insert_entity<T: 'static>(
 933        &mut self,
 934        reservation: crate::Reservation<T>,
 935        build_entity: impl FnOnce(&mut Context<T>) -> T,
 936    ) -> Self::Result<Entity<T>> {
 937        self.cx.insert_entity(reservation, build_entity)
 938    }
 939
 940    fn update_entity<T, R>(
 941        &mut self,
 942        handle: &Entity<T>,
 943        update: impl FnOnce(&mut T, &mut Context<T>) -> R,
 944    ) -> Self::Result<R>
 945    where
 946        T: 'static,
 947    {
 948        self.cx.update_entity(handle, update)
 949    }
 950
 951    fn as_mut<'a, T>(&'a mut self, handle: &Entity<T>) -> Self::Result<super::GpuiBorrow<'a, T>>
 952    where
 953        T: 'static,
 954    {
 955        self.cx.as_mut(handle)
 956    }
 957
 958    fn read_entity<T, R>(
 959        &self,
 960        handle: &Entity<T>,
 961        read: impl FnOnce(&T, &App) -> R,
 962    ) -> Self::Result<R>
 963    where
 964        T: 'static,
 965    {
 966        self.cx.read_entity(handle, read)
 967    }
 968
 969    fn update_window<T, F>(&mut self, window: AnyWindowHandle, f: F) -> Result<T>
 970    where
 971        F: FnOnce(AnyView, &mut Window, &mut App) -> T,
 972    {
 973        self.cx.update_window(window, f)
 974    }
 975
 976    fn read_window<T, R>(
 977        &self,
 978        window: &WindowHandle<T>,
 979        read: impl FnOnce(Entity<T>, &App) -> R,
 980    ) -> Result<R>
 981    where
 982        T: 'static,
 983    {
 984        self.cx.read_window(window, read)
 985    }
 986
 987    fn background_spawn<R>(&self, future: impl Future<Output = R> + Send + 'static) -> Task<R>
 988    where
 989        R: Send + 'static,
 990    {
 991        self.cx.background_spawn(future)
 992    }
 993
 994    fn read_global<G, R>(&self, callback: impl FnOnce(&G, &App) -> R) -> Self::Result<R>
 995    where
 996        G: Global,
 997    {
 998        self.cx.read_global(callback)
 999    }
1000}
1001
1002impl VisualContext for VisualTestContext {
1003    /// Get the underlying window handle underlying this context.
1004    fn window_handle(&self) -> AnyWindowHandle {
1005        self.window
1006    }
1007
1008    fn new_window_entity<T: 'static>(
1009        &mut self,
1010        build_entity: impl FnOnce(&mut Window, &mut Context<T>) -> T,
1011    ) -> Self::Result<Entity<T>> {
1012        self.window
1013            .update(&mut self.cx, |_, window, cx| {
1014                cx.new(|cx| build_entity(window, cx))
1015            })
1016            .unwrap()
1017    }
1018
1019    fn update_window_entity<V: 'static, R>(
1020        &mut self,
1021        view: &Entity<V>,
1022        update: impl FnOnce(&mut V, &mut Window, &mut Context<V>) -> R,
1023    ) -> Self::Result<R> {
1024        self.window
1025            .update(&mut self.cx, |_, window, cx| {
1026                view.update(cx, |v, cx| update(v, window, cx))
1027            })
1028            .unwrap()
1029    }
1030
1031    fn replace_root_view<V>(
1032        &mut self,
1033        build_view: impl FnOnce(&mut Window, &mut Context<V>) -> V,
1034    ) -> Self::Result<Entity<V>>
1035    where
1036        V: 'static + Render,
1037    {
1038        self.window
1039            .update(&mut self.cx, |_, window, cx| {
1040                window.replace_root(cx, build_view)
1041            })
1042            .unwrap()
1043    }
1044
1045    fn focus<V: crate::Focusable>(&mut self, view: &Entity<V>) -> Self::Result<()> {
1046        self.window
1047            .update(&mut self.cx, |_, window, cx| {
1048                view.read(cx).focus_handle(cx).focus(window)
1049            })
1050            .unwrap()
1051    }
1052}
1053
1054impl AnyWindowHandle {
1055    /// Creates the given view in this window.
1056    pub fn build_entity<V: Render + 'static>(
1057        &self,
1058        cx: &mut TestAppContext,
1059        build_view: impl FnOnce(&mut Window, &mut Context<V>) -> V,
1060    ) -> Entity<V> {
1061        self.update(cx, |_, window, cx| cx.new(|cx| build_view(window, cx)))
1062            .unwrap()
1063    }
1064}