snapshot of https://github.com/flutter/samples.git (main, 2026-09-16; blobs > 131072B omitted)

material_3_demo/test/typography_screen_test.dart

@@ -0,0 +1,94 @@
+// Copyright 2021 The Flutter team. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// ignore_for_file: avoid_types_on_closure_parameters
+import 'package:flutter/material.dart';
+import 'package:flutter_test/flutter_test.dart';
+import 'package:material_3_demo/main.dart';
+import 'package:material_3_demo/src/typography_screen.dart';
+
+import 'component_screen_test.dart';
+
+void main() {
+  testWidgets(
+    'Typography screen shows correctly when the corresponding icon is '
+    'selected on NavigationBar',
+    (tester) async {
+      widgetSetup(tester, 449);
+      addTearDown(tester.view.resetPhysicalSize);
+      await tester.pumpWidget(const App());
+
+      expect(find.text('Display Large'), findsNothing);
+      expect(find.byType(NavigationBar), findsOneWidget);
+      Finder textIconOnBar = find.descendant(
+        of: find.byType(NavigationBar),
+        matching: find.byIcon(Icons.text_snippet_outlined),
+      );
+      expect(textIconOnBar, findsOneWidget);
+      await tester.tap(textIconOnBar);
+      await tester.pumpAndSettle(const Duration(microseconds: 500));
+      expect(textIconOnBar, findsNothing);
+      Finder selectedTextIconOnBar = find.descendant(
+        of: find.byType(NavigationBar),
+        matching: find.byIcon(Icons.text_snippet),
+      );
+      expect(selectedTextIconOnBar, findsOneWidget);
+      expect(find.text('Display Large'), findsOneWidget);
+    },
+  );
+
+  testWidgets(
+    'Typography screen shows correctly when the corresponding icon is '
+    'selected on NavigationRail',
+    (tester) async {
+      widgetSetup(
+        tester,
+        1200,
+      ); // NavigationRail shows only when width is > 1000.
+      addTearDown(tester.view.resetPhysicalSize);
+      await tester.pumpWidget(const App());
+      expect(find.text('Display Large'), findsNothing);
+      Finder textIconOnRail = find.descendant(
+        of: find.byType(NavigationRail),
+        matching: find.byIcon(Icons.text_snippet_outlined),
+      );
+      expect(textIconOnRail, findsOneWidget);
+      await tester.tap(textIconOnRail);
+      await tester.pumpAndSettle(const Duration(microseconds: 500));
+      expect(textIconOnRail, findsNothing);
+      Finder selectedTextIconOnRail = find.descendant(
+        of: find.byType(NavigationRail),
+        matching: find.byIcon(Icons.text_snippet),
+      );
+      expect(selectedTextIconOnRail, findsOneWidget);
+      expect(find.text('Display Large'), findsOneWidget);
+    },
+  );
+
+  testWidgets('Typography screen shows correct content', (tester) async {
+    await tester.pumpWidget(
+      const MaterialApp(
+        home: Scaffold(body: Row(children: [TypographyScreen()])),
+      ),
+    );
+    expect(find.text('Display Large'), findsOneWidget);
+    expect(find.text('Display Medium'), findsOneWidget);
+    expect(find.text('Display Small'), findsOneWidget);
+    expect(find.text('Headline Large'), findsOneWidget);
+    expect(find.text('Headline Medium'), findsOneWidget);
+    expect(find.text('Headline Small'), findsOneWidget);
+    expect(find.text('Title Large'), findsOneWidget);
+    expect(find.text('Title Medium'), findsOneWidget);
+    expect(find.text('Title Small'), findsOneWidget);
+    await tester.scrollUntilVisible(find.text('Body Small'), 500.0);
+    expect(find.text('Label Large'), findsOneWidget);
+    expect(find.text('Label Medium'), findsOneWidget);
+    expect(find.text('Label Small'), findsOneWidget);
+    expect(find.text('Body Large'), findsOneWidget);
+    expect(find.text('Body Medium'), findsOneWidget);
+    expect(find.text('Body Small'), findsOneWidget);
+
+    expect(find.byType(TextStyleExample), findsNWidgets(15));
+  });
+}