T23b: AI chat, citations

- CitationBadge: a numbered pill after a claim, its source on hover, a press
  opens it; a Tab stop
- SourceCard and SourceList: the sources folded under their count and sites,
  each a card numbered as cited; the fold opens from the keyboard
- SearchProgress: steps waiting, working and done
- WebResultCard and DocumentChunkPreview with matched words washed
- gallery: citation and sources states

src/chat/tests.rs

@@ -8,7 +8,8 @@ use gpui::{
 };
 
 use super::{
-    ImageMessage, MessageAvatar, MessageBubble, MessageEditor, MessageList, Role, ThinkingBlock,
+    CitationBadge, ImageMessage, MessageAvatar, MessageBubble, MessageEditor, MessageList, Role,
+    Source, SourceList, ThinkingBlock,
 };
 use crate::{forms, forms::TextInput, theme::Theme};
 
@@ -356,3 +357,88 @@ fn the_reasoning_opens_from_the_keyboard(cx: &mut TestAppContext) {
         "Tab and Space open it: {closed:?} to {open:?}"
     );
 }
+
+fn source(title: &str) -> Source {
+    Source {
+        site: "example.com".into(),
+        title: title.to_string().into(),
+        url: "https://example.com".into(),
+        snippet: None,
+    }
+}
+
+/// Sources folded under their count, the list's box measured, and how often one opened.
+struct Cited {
+    frame: Measured,
+    opened: usize,
+}
+
+impl Render for Cited {
+    fn render(&mut self, _: &mut Window, cx: &mut Context<Self>) -> impl IntoElement {
+        let (frame, me) = (self.frame.clone(), cx.entity());
+        div()
+            .size_full()
+            .child(
+                CitationBadge::new("cite", 1, source("Gamma"))
+                    .on_open(move |_, cx| me.update(cx, |cited, _| cited.opened += 1)),
+            )
+            .child(
+                div()
+                    .w(px(320.0))
+                    .relative()
+                    .child(SourceList::new(
+                        "sources",
+                        [source("Gamma"), source("Lift")],
+                    ))
+                    .child(
+                        canvas(
+                            move |bounds, _, _| *frame.borrow_mut() = Some(bounds),
+                            |_, _, _, _| {},
+                        )
+                        .absolute()
+                        .top_0()
+                        .left_0()
+                        .size_full(),
+                    ),
+            )
+    }
+}
+
+fn release(key: &str, cx: &mut VisualTestContext) {
+    cx.simulate_keystrokes(key);
+    cx.simulate_event(KeyUpEvent {
+        keystroke: Keystroke::parse(key).expect("the key parses"),
+    });
+    settle(cx);
+}
+
+#[gpui::test]
+fn citations_and_sources_open_from_the_keyboard(cx: &mut TestAppContext) {
+    cx.update(|cx| {
+        Theme::init(cx);
+        forms::bind_keys(cx);
+    });
+    let frame = Measured::default();
+    let seen = frame.clone();
+    let (cited, cx) = cx.add_window_view(move |_, _| Cited {
+        frame: seen,
+        opened: 0,
+    });
+    cx.update(|window, _| window.activate_window());
+    settle(cx);
+    cx.update(|window, _| window.focus_next());
+    release("enter", cx);
+    assert_eq!(
+        cited.read_with(cx, |cited, _| cited.opened),
+        1,
+        "the badge opens its source"
+    );
+    let folded = frame.borrow().expect("the list is laid out").size.height;
+    cx.update(|window, _| window.focus_next());
+    release("space", cx);
+    let open = frame.borrow().expect("the list is laid out").size.height;
+    assert!(
+        open > folded,
+        "Tab and Space open the sources: {folded:?} to {open:?}"
+    );
+}