add list

crates/data/tests/list.rs

@@ -0,0 +1,140 @@
+use std::{cell::RefCell, rc::Rc};
+
+use gpui::{
+    Context, IntoElement, Modifiers, MouseButton, ParentElement as _, Render, Styled as _,
+    TestAppContext, VisualTestContext, Window, WindowHandle, div, point, px,
+};
+use gpui_native_data::list::{List, ListItem};
+use gpui_native_theme::Theme;
+
+struct Harness {
+    selected: Option<usize>,
+    changes: Rc<RefCell<Vec<Option<usize>>>>,
+}
+
+impl Render for Harness {
+    fn render(&mut self, _window: &mut Window, cx: &mut Context<Self>) -> impl IntoElement {
+        let changes = self.changes.clone();
+        let view = cx.entity();
+        div().size_full().child(
+            List::new("test-list")
+                .selected(self.selected)
+                .on_change(move |next, _, cx| {
+                    changes.borrow_mut().push(next);
+                    view.update(cx, |harness, cx| {
+                        harness.selected = next;
+                        cx.notify();
+                    });
+                })
+                .items(|_, _| {
+                    vec![
+                        ListItem::new("One"),
+                        ListItem::new("Two"),
+                        ListItem::new("Unavailable").disabled(true),
+                        ListItem::new("Three"),
+                    ]
+                }),
+        )
+    }
+}
+
+type Changes = Rc<RefCell<Vec<Option<usize>>>>;
+
+type ListWindow = (
+    TestAppContext,
+    VisualTestContext,
+    WindowHandle<Harness>,
+    Changes,
+);
+
+/// Rows paint at the top-left with no outer padding: one row per ~34 px band
+/// (16 px text line + 2×4 px padding + 2 px gap), so clicks at `(50, 16/48/80/112)`
+/// land on One / Two / the disabled Unavailable / Three.
+fn list_window(selected: Option<usize>) -> ListWindow {
+    let mut cx = TestAppContext::single();
+    cx.update(Theme::init);
+    let changes = Rc::new(RefCell::new(Vec::new()));
+    let harness_changes = changes.clone();
+    let window = cx.add_window(move |_, _| Harness {
+        selected,
+        changes: harness_changes,
+    });
+    let mut visual = VisualTestContext::from_window(window.into(), &cx);
+    visual.update(|window, cx| {
+        window.draw(cx).clear(cx);
+    });
+    (cx, visual, window, changes)
+}
+
+fn draw(visual: &mut VisualTestContext) {
+    visual.update(|window, cx| {
+        window.draw(cx).clear(cx);
+    });
+}
+
+fn click(visual: &mut VisualTestContext, position: gpui::Point<gpui::Pixels>) {
+    visual.simulate_mouse_down(position, MouseButton::Left, Modifiers::default());
+    visual.simulate_mouse_up(position, MouseButton::Left, Modifiers::default());
+}
+
+#[test]
+fn clicking_a_row_selects_it_and_hands_the_list_the_keyboard() {
+    let (_cx, mut visual, _window, changes) = list_window(None);
+
+    click(&mut visual, point(px(50.), px(16.)));
+    assert_eq!(*changes.borrow(), vec![Some(0)]);
+
+    // The click focused the list, so the arrows navigate from here.
+    visual.simulate_keystrokes("down");
+    draw(&mut visual);
+    assert_eq!(*changes.borrow(), vec![Some(0), Some(1)]);
+}
+
+#[test]
+fn clicking_a_disabled_row_reports_nothing() {
+    let (_cx, mut visual, _window, changes) = list_window(None);
+
+    click(&mut visual, point(px(50.), px(80.)));
+    draw(&mut visual);
+    assert_eq!(*changes.borrow(), Vec::<Option<usize>>::new());
+}
+
+#[test]
+fn keyboard_navigation_skips_disabled_rows_and_never_wraps() {
+    let (_cx, mut visual, _window, changes) = list_window(None);
+
+    click(&mut visual, point(px(50.), px(16.)));
+    visual.simulate_keystrokes("down"); // over the disabled row → Two
+    visual.simulate_keystrokes("down"); // over the disabled row → Three
+    visual.simulate_keystrokes("down"); // last selectable; no wrap
+    draw(&mut visual);
+    assert_eq!(*changes.borrow(), vec![Some(0), Some(1), Some(3)]);
+
+    visual.simulate_keystrokes("home");
+    visual.simulate_keystrokes("end");
+    visual.simulate_keystrokes("up"); // over the disabled row → Two
+    draw(&mut visual);
+    assert_eq!(
+        *changes.borrow(),
+        vec![Some(0), Some(1), Some(3), Some(0), Some(3), Some(1)]
+    );
+}
+
+#[test]
+fn arrow_down_with_no_selection_picks_the_first_selectable_row() {
+    let (mut cx, mut visual, window, changes) = list_window(Some(1));
+
+    // Focus the list, then clear the selection app-side.
+    click(&mut visual, point(px(50.), px(48.)));
+    window
+        .update(&mut cx, |harness, _, cx| {
+            harness.selected = None;
+            cx.notify();
+        })
+        .unwrap();
+    draw(&mut visual);
+
+    visual.simulate_keystrokes("down");
+    draw(&mut visual);
+    assert_eq!(*changes.borrow(), vec![Some(1), Some(0)]);
+}