feat(flutter): DelayedLoading wrapper for skeleton-with-delay

Renders nothing for the first [delay] (default 200ms) of sustained loading, then renders the [whileDelayed] child until loading completes. Mirrors the web useDelayed hook so a fast network response doesn't flash a skeleton. Used in the next commit's home screen rewrite; otherwise unused this slice. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
2026-05-09 11:38:42 -04:00
parent 3ac8cc9363
commit a7fcafadda
2 changed files with 142 additions and 0 deletions
@@ -0,0 +1,76 @@
+import 'package:flutter/material.dart';
+import 'package:flutter_test/flutter_test.dart';
+
+import 'package:minstrel/shared/delayed_loading.dart';
+
+void main() {
+  testWidgets('renders nothing for the first 100ms of loading', (tester) async {
+    await tester.pumpWidget(const MaterialApp(
+      home: DelayedLoading(
+        isLoading: true,
+        delay: Duration(milliseconds: 200),
+        whileDelayed: Text('LOADING'),
+        whenReady: Text('READY'),
+      ),
+    ));
+    await tester.pump(const Duration(milliseconds: 100));
+    expect(find.text('LOADING'), findsNothing);
+    expect(find.text('READY'), findsNothing);
+  });
+
+  testWidgets('renders whileDelayed after delay elapses', (tester) async {
+    await tester.pumpWidget(const MaterialApp(
+      home: DelayedLoading(
+        isLoading: true,
+        delay: Duration(milliseconds: 200),
+        whileDelayed: Text('LOADING'),
+        whenReady: Text('READY'),
+      ),
+    ));
+    await tester.pump(const Duration(milliseconds: 250));
+    expect(find.text('LOADING'), findsOneWidget);
+  });
+
+  testWidgets('renders whenReady when not loading', (tester) async {
+    await tester.pumpWidget(const MaterialApp(
+      home: DelayedLoading(
+        isLoading: false,
+        whileDelayed: Text('LOADING'),
+        whenReady: Text('READY'),
+      ),
+    ));
+    expect(find.text('READY'), findsOneWidget);
+  });
+
+  testWidgets('resets timer when isLoading flips false then true', (tester) async {
+    await tester.pumpWidget(const MaterialApp(
+      home: DelayedLoading(
+        isLoading: true,
+        delay: Duration(milliseconds: 200),
+        whileDelayed: Text('LOADING'),
+        whenReady: Text('READY'),
+      ),
+    ));
+    await tester.pump(const Duration(milliseconds: 150));
+    // Switch to not-loading, then back to loading.
+    await tester.pumpWidget(const MaterialApp(
+      home: DelayedLoading(
+        isLoading: false,
+        whileDelayed: Text('LOADING'),
+        whenReady: Text('READY'),
+      ),
+    ));
+    await tester.pumpWidget(const MaterialApp(
+      home: DelayedLoading(
+        isLoading: true,
+        delay: Duration(milliseconds: 200),
+        whileDelayed: Text('LOADING'),
+        whenReady: Text('READY'),
+      ),
+    ));
+    // Original 150ms shouldn't carry over — at 100ms past restart
+    // we should still see nothing.
+    await tester.pump(const Duration(milliseconds: 100));
+    expect(find.text('LOADING'), findsNothing);
+  });
+}