implement MultitabPane widget + controller (T-83)

MultitabController<T> is a Flutter-free ChangeNotifier owning the tab list, active selection, and reorder/close invariants: - pinned (non-reorderable) entries form barriers that other tabs cannot cross - non-closeable entries silently no-op on remove() so hosts don't need to gate the call site - closing the active tab falls right, then left, then to null - duplicate ids are rejected MultitabPane<T> is the widget shell: a horizontal tab strip followed by the active entry's body. Active tab gets the panelHeader background and a panelActiveBorder top accent; inactive tabs blend into the tab bar. Close × is hidden until hover. Add button only renders when onAddRequested is wired. Hosts route the user's add/close intent through callbacks so the widget stays domain-free — for the Claude pane, add will spawn a new tmux session and close will kill one. Drag-to-reorder is controller-side only for now (the gesture wiring lands with T-24). 19 controller tests + 9 widget tests. Co-Authored-By: Claude <noreply@anthropic.com>
2026-05-06 12:12:42 +02:00
parent bdc46a4fdd
commit 1caaf5f4dd
7 changed files with 776 additions and 1 deletions
@@ -0,0 +1,155 @@
+import 'package:clide/widgets/widgets.dart';
+import 'package:flutter/widgets.dart';
+import 'package:flutter_test/flutter_test.dart';
+
+import '../helpers/kernel_fixture.dart';
+import '../helpers/widget_harness.dart';
+
+MultitabEntry<String> entry(String id, {bool closeable = true, bool reorderable = true}) {
+  return MultitabEntry<String>(
+    id: id,
+    title: id,
+    payload: id,
+    closeable: closeable,
+    reorderable: reorderable,
+  );
+}
+
+Widget body(BuildContext _, MultitabEntry<String> e) =>
+    SizedBox(key: ValueKey('body-${e.id}'), child: Text('body:${e.payload}'));
+
+void main() {
+  group('MultitabPane', () {
+    late KernelFixture f;
+    setUp(() async => f = await KernelFixture.create());
+    tearDown(() => f.dispose());
+
+    testWidgets('renders one tab per entry and the active body', (tester) async {
+      final c = MultitabController<String>(
+        initial: [entry('primary', closeable: false), entry('s1'), entry('s2')],
+      );
+      await tester.pumpWidget(
+        harness(f, MultitabPane<String>(controller: c, bodyBuilder: body)),
+      );
+
+      expect(find.text('primary'), findsOneWidget);
+      expect(find.text('s1'), findsOneWidget);
+      expect(find.text('s2'), findsOneWidget);
+      // Body of the active (first) tab is visible.
+      expect(find.byKey(const ValueKey('body-primary')), findsOneWidget);
+      expect(find.byKey(const ValueKey('body-s1')), findsNothing);
+    });
+
+    testWidgets('tapping a tab activates it and swaps the body', (tester) async {
+      final c = MultitabController<String>(initial: [entry('a'), entry('b')]);
+      await tester.pumpWidget(
+        harness(f, MultitabPane<String>(controller: c, bodyBuilder: body)),
+      );
+      expect(find.byKey(const ValueKey('body-a')), findsOneWidget);
+
+      await tester.tap(find.text('b'));
+      await tester.pumpAndSettle();
+
+      expect(c.activeId, 'b');
+      expect(find.byKey(const ValueKey('body-b')), findsOneWidget);
+      expect(find.byKey(const ValueKey('body-a')), findsNothing);
+    });
+
+    testWidgets('add button calls onAddRequested when set', (tester) async {
+      final c = MultitabController<String>(initial: [entry('a')]);
+      var added = 0;
+      await tester.pumpWidget(
+        harness(
+          f,
+          MultitabPane<String>(
+            controller: c,
+            bodyBuilder: body,
+            onAddRequested: () => added++,
+          ),
+        ),
+      );
+
+      await tester.tap(find.bySemanticsLabel('New tab'));
+      await tester.pumpAndSettle();
+      expect(added, 1);
+    });
+
+    testWidgets('add button is absent when onAddRequested is null', (tester) async {
+      final c = MultitabController<String>(initial: [entry('a')]);
+      await tester.pumpWidget(
+        harness(f, MultitabPane<String>(controller: c, bodyBuilder: body)),
+      );
+      expect(find.bySemanticsLabel('New tab'), findsNothing);
+    });
+
+    testWidgets('non-closeable tabs do not render a close glyph', (tester) async {
+      final c = MultitabController<String>(
+        initial: [entry('p', closeable: false), entry('s')],
+      );
+      await tester.pumpWidget(
+        harness(f, MultitabPane<String>(controller: c, bodyBuilder: body)),
+      );
+      // A pinned tab has no close target; a closeable one does (it's
+      // hidden via Opacity until hover, but still in the tree).
+      // Two tabs total, one × glyph for 's'.
+      expect(find.text('×'), findsOneWidget);
+    });
+
+    testWidgets('default close behavior removes the entry', (tester) async {
+      final c = MultitabController<String>(
+        initial: [entry('p', closeable: false), entry('s')],
+      );
+      await tester.pumpWidget(
+        harness(f, MultitabPane<String>(controller: c, bodyBuilder: body)),
+      );
+
+      await tester.tap(find.text('×'));
+      await tester.pumpAndSettle();
+
+      expect(c.entries.map((e) => e.id), ['p']);
+    });
+
+    testWidgets('onCloseRequested overrides default removal', (tester) async {
+      final c = MultitabController<String>(initial: [entry('a'), entry('b')]);
+      MultitabEntry<String>? closed;
+      await tester.pumpWidget(
+        harness(
+          f,
+          MultitabPane<String>(
+            controller: c,
+            bodyBuilder: body,
+            onCloseRequested: (e) => closed = e,
+          ),
+        ),
+      );
+
+      // Both tabs are closeable; tap the first × encountered.
+      await tester.tap(find.text('×').first);
+      await tester.pumpAndSettle();
+
+      expect(closed, isNotNull);
+      // Host decided not to remove yet — entries are unchanged.
+      expect(c.entries.length, 2);
+    });
+
+    testWidgets('rebuilds when the controller notifies', (tester) async {
+      final c = MultitabController<String>(initial: [entry('a')]);
+      await tester.pumpWidget(
+        harness(f, MultitabPane<String>(controller: c, bodyBuilder: body)),
+      );
+      expect(find.bySemanticsLabel('b'), findsNothing);
+
+      c.add(entry('b'));
+      await tester.pumpAndSettle();
+      expect(find.bySemanticsLabel('b'), findsOneWidget);
+    });
+
+    testWidgets('empty controller renders no body', (tester) async {
+      final c = MultitabController<String>();
+      await tester.pumpWidget(
+        harness(f, MultitabPane<String>(controller: c, bodyBuilder: body)),
+      );
+      expect(find.byKey(const ValueKey('body-a')), findsNothing);
+    });
+  });
+}