#280: a drag released off the window ends where the pointer was last seen, not mid-canvas; the test follows #278

crates/ui-egui/src/canvas.rs

@@ -371,16 +371,12 @@ fn input(app: &mut FigApp, ui: &mut Ui, resp: &egui::Response) -> bool {
         }
     }
     let Some(pos) = hover_pos.filter(|p| app.canvas.rect.contains(*p)) else {
-        if app.canvas.dragging && ctx.input(|i| i.pointer.button_released(egui::PointerButton::Primary)) {
+        // A drag released off the canvas, or off the window, ends where the pointer was last seen.
+        if app.canvas.dragging && !ctx.input(|i| i.pointer.primary_down()) {
             app.canvas.dragging = false;
-            let pos = hover_pos.unwrap_or(app.canvas.rect.center());
-            let ev = pointer_event(app, PointerKind::Up, pos, &mods);
-            app.canvas.pressure = None;
-            app.canvas.last_pointer = Some(Point::new(ev.x, ev.y));
-            if let Err(e) = app.session.pointer(&ev) {
-                app.toast(e.to_string());
+            if let Some(at) = hover_pos.or_else(|| app.canvas.last_pointer.map(|p| app.to_screen(p.x, p.y))) {
+                send(app, PointerKind::Up, at, &mods);
             }
-            app.handle_ui_requests();
         }
         // Leaving the canvas: nothing is hovered there any more.
         if !app.canvas.dragging && std::mem::take(&mut app.canvas.hovering) {
@@ -493,19 +489,24 @@ fn input(app: &mut FigApp, ui: &mut Ui, resp: &egui::Response) -> bool {
         app.canvas.pressure = force;
     }
     if let Some(k) = kind {
-        let ev = pointer_event(app, k, pos, &mods);
-        if k == PointerKind::Up {
-            app.canvas.pressure = None;
-        }
-        app.canvas.last_pointer = Some(Point::new(ev.x, ev.y));
-        if let Err(e) = app.session.pointer(&ev) {
-            app.toast(e.to_string());
-        }
-        app.handle_ui_requests();
+        send(app, k, pos, &mods);
     }
     true
 }
 
+/// Pointer event `kind` at screen point `pos`, to the tools.
+fn send(app: &mut FigApp, kind: PointerKind, pos: Pos2, m: &egui::Modifiers) {
+    let ev = pointer_event(app, kind, pos, m);
+    if kind == PointerKind::Up {
+        app.canvas.pressure = None;
+    }
+    app.canvas.last_pointer = Some(Point::new(ev.x, ev.y));
+    if let Err(e) = app.session.pointer(&ev) {
+        app.toast(e.to_string());
+    }
+    app.handle_ui_requests();
+}
+
 /// Right-click at screen `pos`: select what's under the pointer (`deep`: the nested layer), then
 /// open the context menu there.
 pub fn open_context_menu(app: &mut FigApp, pos: Pos2, deep: bool) {

crates/ui-egui/src/canvas_drag_tests.rs

@@ -75,3 +75,49 @@ fn releasing_a_canvas_drag_outside_finishes_the_interaction() {
 
     assert!(u.app.session.ds().unwrap().interaction.is_none(), "the document interaction is committed");
 }
+
+fn key(u: &mut Ui, key: egui::Key) {
+    let modifiers = egui::Modifiers::NONE;
+    u.frame(vec![
+        Event::Key { key, physical_key: None, pressed: true, repeat: false, modifiers },
+        Event::Key { key, physical_key: None, pressed: false, repeat: false, modifiers },
+    ]);
+}
+
+#[test]
+fn a_drag_released_off_the_window_ends_where_the_pointer_was_last_seen_and_later_edits_stay() {
+    // #278: a drag left open made a later text edit roll back the changes made since.
+    let mut s = Session::new();
+    let id = |v: serde_json::Value| figcraft_engine::params::id_of(&v["id"]).unwrap();
+    let kept = id(s.execute("shape.rectangle", &json!({"x": 40, "y": 400, "width": 80, "height": 40})).unwrap());
+    let gone = id(s.execute("shape.rectangle", &json!({"x": 160, "y": 400, "width": 80, "height": 40})).unwrap());
+    let text = id(s.execute("text.create", &json!({"text": "A", "x": 40, "y": 500})).unwrap());
+    s.execute("tool.rectangle", &json!({})).unwrap();
+    let mut u = Ui::new(s);
+    // A rectangle drawn from the middle of the canvas, released off the window, the pointer gone.
+    let start = u.app.canvas.rect.center();
+    u.button(start, true);
+    for i in 1..=6 {
+        u.frame(vec![Event::PointerMoved(start + vec2(10.0, 6.0) * i as f32)]);
+    }
+    let release =
+        Event::PointerButton { pos: egui::pos2(-50.0, -50.0), button: egui::PointerButton::Primary, pressed: false, modifiers: Default::default() };
+    u.frame(vec![release, Event::PointerGone]);
+    let ds = u.app.session.ds().unwrap();
+    assert!(ds.interaction.is_none(), "the drawing is committed");
+    let (drawn, zoom) = (ds.selection[0], ds.view.zoom);
+    let b = ds.doc.world_bounds(drawn).unwrap();
+    // Not the 100 x 100 shape of a click, as an end in the middle of the canvas would make.
+    assert!((b.width() * zoom - 60.0).abs() < 1.5 && (b.height() * zoom - 36.0).abs() < 1.5, "{b:?} at zoom {zoom}");
+    // #278's steps: a move in the panel, a delete, then a text edit.
+    u.app.run("node.set", json!({"ids": [kept], "props": {"x": 650}}));
+    u.app.run("edit.delete", json!({"ids": [gone]}));
+    u.app.run("select.set", json!({"ids": [text]}));
+    key(&mut u, egui::Key::Enter);
+    u.frame(vec![Event::Text("B".into())]);
+    key(&mut u, egui::Key::Escape);
+    let doc = u.app.session.doc().unwrap();
+    assert_eq!(doc.world_bounds(kept).unwrap().x0, 650.0, "the move stays");
+    assert!(!doc.contains(gone), "the delete stays");
+    assert_eq!(doc.node(text).unwrap().kind.text().unwrap().characters, "B");
+}