Start on adding a randomized test for `BackgroundWrapper`

Antonio Scandurra and Nathan Sobo created

Co-Authored-By: Nathan Sobo <nathan@zed.dev>

Change summary

gpui/src/app.rs                        |  24 +++--
gpui/src/lib.rs                        |   2 
zed/src/editor/display_map.rs          |   4 
zed/src/editor/display_map/wrap_map.rs | 111 +++++++++++++++++++++++----
4 files changed, 111 insertions(+), 30 deletions(-)

Detailed changes

gpui/src/app.rs 🔗

@@ -147,7 +147,7 @@ impl App {
         let cx = app.0.clone();
         foreground_platform.on_menu_command(Box::new(move |command, arg| {
             let mut cx = cx.borrow_mut();
-            if let Some(key_window_id) = cx.platform.key_window_id() {
+            if let Some(key_window_id) = cx.cx.platform.key_window_id() {
                 if let Some((presenter, _)) = cx.presenters_and_platform_windows.get(&key_window_id)
                 {
                     let presenter = presenter.clone();
@@ -374,7 +374,7 @@ impl TestAppContext {
     }
 
     pub fn platform(&self) -> Arc<dyn platform::Platform> {
-        self.cx.borrow().platform.clone()
+        self.cx.borrow().cx.platform.clone()
     }
 
     pub fn foreground(&self) -> Rc<executor::Foreground> {
@@ -566,7 +566,6 @@ type GlobalActionCallback = dyn FnMut(&dyn Any, &mut MutableAppContext);
 pub struct MutableAppContext {
     weak_self: Option<rc::Weak<RefCell<Self>>>,
     foreground_platform: Rc<dyn platform::ForegroundPlatform>,
-    platform: Arc<dyn platform::Platform>,
     assets: Arc<AssetCache>,
     cx: AppContext,
     actions: HashMap<TypeId, HashMap<String, Vec<Box<ActionCallback>>>>,
@@ -598,7 +597,6 @@ impl MutableAppContext {
         Self {
             weak_self: None,
             foreground_platform,
-            platform,
             assets: Arc::new(AssetCache::new(asset_source)),
             cx: AppContext {
                 models: Default::default(),
@@ -608,6 +606,7 @@ impl MutableAppContext {
                 ref_counts: Arc::new(Mutex::new(RefCounts::default())),
                 background,
                 font_cache: Arc::new(FontCache::new(fonts)),
+                platform,
             },
             actions: HashMap::new(),
             global_actions: HashMap::new(),
@@ -631,7 +630,7 @@ impl MutableAppContext {
     }
 
     pub fn platform(&self) -> Arc<dyn platform::Platform> {
-        self.platform.clone()
+        self.cx.platform.clone()
     }
 
     pub fn font_cache(&self) -> &Arc<FontCache> {
@@ -992,7 +991,7 @@ impl MutableAppContext {
     }
 
     fn open_platform_window(&mut self, window_id: usize) {
-        let mut window = self.platform.open_window(
+        let mut window = self.cx.platform.open_window(
             window_id,
             WindowOptions {
                 bounds: RectF::new(vec2f(0., 0.), vec2f(1024., 768.)),
@@ -1000,7 +999,7 @@ impl MutableAppContext {
             },
             self.foreground.clone(),
         );
-        let text_layout_cache = TextLayoutCache::new(self.platform.fonts());
+        let text_layout_cache = TextLayoutCache::new(self.cx.platform.fonts());
         let presenter = Rc::new(RefCell::new(Presenter::new(
             window_id,
             self.cx.font_cache.clone(),
@@ -1387,11 +1386,11 @@ impl MutableAppContext {
     }
 
     pub fn write_to_clipboard(&self, item: ClipboardItem) {
-        self.platform.write_to_clipboard(item);
+        self.cx.platform.write_to_clipboard(item);
     }
 
     pub fn read_from_clipboard(&self) -> Option<ClipboardItem> {
-        self.platform.read_from_clipboard()
+        self.cx.platform.read_from_clipboard()
     }
 }
 
@@ -1485,6 +1484,7 @@ pub struct AppContext {
     background: Arc<executor::Background>,
     ref_counts: Arc<Mutex<RefCounts>>,
     font_cache: Arc<FontCache>,
+    platform: Arc<dyn Platform>,
 }
 
 impl AppContext {
@@ -1524,10 +1524,14 @@ impl AppContext {
         &self.background
     }
 
-    pub fn font_cache(&self) -> &FontCache {
+    pub fn font_cache(&self) -> &Arc<FontCache> {
         &self.font_cache
     }
 
+    pub fn platform(&self) -> &Arc<dyn Platform> {
+        &self.platform
+    }
+
     pub fn value<Tag: 'static, T: 'static + Default>(&self, id: usize) -> ValueHandle<T> {
         let key = (TypeId::of::<Tag>(), id);
         let mut values = self.values.write();

gpui/src/lib.rs 🔗

@@ -25,7 +25,7 @@ pub mod json;
 pub mod keymap;
 mod platform;
 pub use gpui_macros::test;
-pub use platform::{Event, PathPromptOptions, Platform, PromptLevel};
+pub use platform::{Event, FontSystem, PathPromptOptions, Platform, PromptLevel};
 pub use presenter::{
     AfterLayoutContext, Axis, DebugContext, EventContext, LayoutContext, PaintContext,
     SizeConstraint, Vector2FExt,

zed/src/editor/display_map.rs 🔗

@@ -21,7 +21,9 @@ impl DisplayMap {
         let fold_map = FoldMap::new(buffer.clone(), cx);
         let (snapshot, edits) = fold_map.read(cx);
         assert_eq!(edits.len(), 0);
-        let wrap_map = WrapMap::new(snapshot, cx);
+        // TODO: take `wrap_width` as a parameter.
+        let config = { todo!() };
+        let wrap_map = WrapMap::new(snapshot, config, cx);
         DisplayMap {
             buffer,
             fold_map,

zed/src/editor/display_map/wrap_map.rs 🔗

@@ -1,9 +1,12 @@
+use std::sync::Arc;
+
 use crate::{
     editor::{display_map::fold_map, Point, TextSummary},
+    settings::Settings,
     sum_tree::{self, SumTree},
     util::Bias,
 };
-use gpui::{AppContext, Task};
+use gpui::{font_cache::FamilyId, AppContext, FontCache, FontSystem, Task};
 use parking_lot::Mutex;
 use postage::{prelude::Sink, watch};
 use smol::channel;
@@ -19,6 +22,12 @@ struct State {
     interpolated_version: usize,
 }
 
+pub struct Config {
+    pub wrap_width: f32,
+    pub font_family: FamilyId,
+    pub font_size: f32,
+}
+
 pub struct WrapMap {
     state: Mutex<State>,
     edits_tx: channel::Sender<(fold_map::Snapshot, Vec<fold_map::Edit>)>,
@@ -27,7 +36,9 @@ pub struct WrapMap {
 }
 
 impl WrapMap {
-    pub fn new(folds_snapshot: fold_map::Snapshot, cx: &AppContext) -> Self {
+    pub fn new(folds_snapshot: fold_map::Snapshot, config: Config, cx: &AppContext) -> Self {
+        let font_cache = cx.font_cache().clone();
+        let font_system = cx.platform().fonts();
         let snapshot = Snapshot {
             transforms: SumTree::from_item(
                 Transform {
@@ -45,8 +56,10 @@ impl WrapMap {
             watch::channel_with(snapshot.clone());
         let (edits_tx, edits_rx) = channel::unbounded();
         let background_task = cx.background().spawn(async move {
-            let mut wrapper = BackgroundWrapper::new(edits_rx, background_snapshots_tx);
-            wrapper.run(folds_snapshot).await;
+            let mut wrapper = BackgroundWrapper::new(config, font_cache, font_system);
+            wrapper
+                .run(folds_snapshot, edits_rx, background_snapshots_tx)
+                .await;
         });
 
         Self {
@@ -68,19 +81,18 @@ impl WrapMap {
 }
 
 struct BackgroundWrapper {
-    edits_rx: channel::Receiver<(fold_map::Snapshot, Vec<fold_map::Edit>)>,
-    snapshots_tx: watch::Sender<Snapshot>,
+    config: Config,
+    font_cache: Arc<FontCache>,
+    font_system: Arc<dyn FontSystem>,
     snapshot: Snapshot,
 }
 
 impl BackgroundWrapper {
-    fn new(
-        edits_rx: channel::Receiver<(fold_map::Snapshot, Vec<fold_map::Edit>)>,
-        snapshots_tx: watch::Sender<Snapshot>,
-    ) -> Self {
+    fn new(config: Config, font_cache: Arc<FontCache>, font_system: Arc<dyn FontSystem>) -> Self {
         Self {
-            edits_rx,
-            snapshots_tx,
+            config,
+            font_cache,
+            font_system,
             snapshot: Snapshot {
                 transforms: Default::default(),
                 version: Default::default(),
@@ -88,23 +100,30 @@ impl BackgroundWrapper {
         }
     }
 
-    async fn run(&mut self, snapshot: fold_map::Snapshot) {
+    async fn run(
+        &mut self,
+        snapshot: fold_map::Snapshot,
+        edits_rx: channel::Receiver<(fold_map::Snapshot, Vec<fold_map::Edit>)>,
+        mut snapshots_tx: watch::Sender<Snapshot>,
+    ) {
         let edit = fold_map::Edit {
             old_bytes: 0..0,
             new_bytes: 0..snapshot.len(),
         };
-        if !self.sync(snapshot, vec![edit]).await {
+        self.sync(snapshot, vec![edit]);
+        if snapshots_tx.send(self.snapshot.clone()).await.is_err() {
             return;
         }
 
-        while let Ok((snapshot, edits)) = self.edits_rx.recv().await {
-            if !self.sync(snapshot, edits).await {
+        while let Ok((snapshot, edits)) = edits_rx.recv().await {
+            self.sync(snapshot, edits);
+            if snapshots_tx.send(self.snapshot.clone()).await.is_err() {
                 break;
             }
         }
     }
 
-    async fn sync(&mut self, snapshot: fold_map::Snapshot, edits: Vec<fold_map::Edit>) -> bool {
+    fn sync(&mut self, snapshot: fold_map::Snapshot, edits: Vec<fold_map::Edit>) {
         let mut new_transforms = SumTree::new();
         {
             // let mut old_cursor = self.snapshot.transforms.cursor::<Point, ()>();
@@ -118,7 +137,6 @@ impl BackgroundWrapper {
 
         self.snapshot.transforms = new_transforms;
         self.snapshot.version = snapshot.version;
-        self.snapshots_tx.send(self.snapshot.clone()).await.is_ok()
     }
 }
 
@@ -156,3 +174,60 @@ impl<'a> sum_tree::Dimension<'a, TransformSummary> for Point {
         *self += &summary.folded.lines;
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use crate::editor::display_map::fold_map::FoldMap;
+    use crate::editor::{Buffer, ToPoint};
+    use crate::util::RandomCharIter;
+    use rand::prelude::*;
+    use std::env;
+    use Bias::{Left, Right};
+
+    #[gpui::test]
+    fn test_random_folds(cx: &mut gpui::MutableAppContext) {
+        let iterations = env::var("ITERATIONS")
+            .map(|i| i.parse().expect("invalid `ITERATIONS` variable"))
+            .unwrap_or(100);
+        let operations = env::var("OPERATIONS")
+            .map(|i| i.parse().expect("invalid `OPERATIONS` variable"))
+            .unwrap_or(10);
+        let seed_range = if let Ok(seed) = env::var("SEED") {
+            let seed = seed.parse().expect("invalid `SEED` variable");
+            seed..seed + 1
+        } else {
+            0..iterations
+        };
+
+        for seed in seed_range {
+            dbg!(seed);
+            let mut rng = StdRng::seed_from_u64(seed);
+
+            let buffer = cx.add_model(|cx| {
+                let len = rng.gen_range(0..10);
+                let text = RandomCharIter::new(&mut rng).take(len).collect::<String>();
+                Buffer::new(0, text, cx)
+            });
+            let fold_map = FoldMap::new(buffer.clone(), cx.as_ref());
+            let (snapshot, _) = fold_map.read(cx.as_ref());
+            let font_cache = cx.font_cache().clone();
+            let font_system = cx.platform().fonts();
+            let config = Config {
+                wrap_width: rng.gen_range(100.0..=1000.0),
+                font_family: font_cache.load_family(&["Helvetica"]).unwrap(),
+                font_size: 14.0,
+            };
+            let mut wrapper = BackgroundWrapper::new(config, font_cache.clone(), font_system);
+            let edit = fold_map::Edit {
+                old_bytes: 0..0,
+                new_bytes: 0..snapshot.len(),
+            };
+            wrapper.sync(snapshot, vec![edit]);
+            // for line in wrapper.snapshot.text().lines() {
+            //     font_cache.
+            // }
+            // assert_eq!(wrap_map.snapshot().text())
+        }
+    }
+}