flutter_flutter/packages/flutter/test/material/back_button_test.dart

// Copyright 2014 The Flutter Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

import 'dart:ui' show PointerDeviceKind;

import 'package:flutter/foundation.dart';
import 'package:flutter/material.dart';
import 'package:flutter/rendering.dart' show RendererBinding;
import 'package:flutter_test/flutter_test.dart';

void main() {
  group('BackButton', () {
    testWidgets('BackButton control test', (WidgetTester tester) async {
      await tester.pumpWidget(
        MaterialApp(
          home: const Material(child: Text('Home')),
          routes: <String, WidgetBuilder>{
            '/next': (BuildContext context) {
              return const Material(child: Center(child: BackButton()));
            },
          },
        ),
      );

      tester.state<NavigatorState>(find.byType(Navigator)).pushNamed('/next');

      await tester.pumpAndSettle();

      await tester.tap(find.byType(BackButton));

      await tester.pumpAndSettle();

      expect(find.text('Home'), findsOneWidget);
    });

    testWidgets('BackButton onPressed overrides default pop behavior', (WidgetTester tester) async {
      bool customCallbackWasCalled = false;
      await tester.pumpWidget(
        MaterialApp(
          home: const Material(child: Text('Home')),
          routes: <String, WidgetBuilder>{
            '/next': (BuildContext context) {
              return Material(
                child: Center(child: BackButton(onPressed: () => customCallbackWasCalled = true)),
              );
            },
          },
        ),
      );

      tester.state<NavigatorState>(find.byType(Navigator)).pushNamed('/next');

      await tester.pumpAndSettle();

      expect(find.text('Home'), findsNothing); // Start off on the second page.
      expect(customCallbackWasCalled, false); // customCallbackWasCalled should still be false.
      await tester.tap(find.byType(BackButton));

      await tester.pumpAndSettle();

      // We're still on the second page.
      expect(find.text('Home'), findsNothing);
      // But the custom callback is called.
      expect(customCallbackWasCalled, true);
    });

    testWidgets('BackButton icon', (WidgetTester tester) async {
      final Key androidKey = UniqueKey();
      final Key iOSKey = UniqueKey();
      final Key linuxKey = UniqueKey();
      final Key macOSKey = UniqueKey();
      final Key windowsKey = UniqueKey();

      await tester.pumpWidget(
        MaterialApp(
          home: Column(
            children: <Widget>[
              Theme(
                data: ThemeData(platform: TargetPlatform.android),
                child: BackButtonIcon(key: androidKey),
              ),
              Theme(
                data: ThemeData(platform: TargetPlatform.iOS),
                child: BackButtonIcon(key: iOSKey),
              ),
              Theme(
                data: ThemeData(platform: TargetPlatform.linux),
                child: BackButtonIcon(key: linuxKey),
              ),
              Theme(
                data: ThemeData(platform: TargetPlatform.macOS),
                child: BackButtonIcon(key: macOSKey),
              ),
              Theme(
                data: ThemeData(platform: TargetPlatform.windows),
                child: BackButtonIcon(key: windowsKey),
              ),
            ],
          ),
        ),
      );

      final Icon androidIcon = tester.widget(
        find.descendant(of: find.byKey(androidKey), matching: find.byType(Icon)),
      );
      final Icon iOSIcon = tester.widget(
        find.descendant(of: find.byKey(iOSKey), matching: find.byType(Icon)),
      );
      final Icon linuxIcon = tester.widget(
        find.descendant(of: find.byKey(linuxKey), matching: find.byType(Icon)),
      );
      final Icon macOSIcon = tester.widget(
        find.descendant(of: find.byKey(macOSKey), matching: find.byType(Icon)),
      );
      final Icon windowsIcon = tester.widget(
        find.descendant(of: find.byKey(windowsKey), matching: find.byType(Icon)),
      );
      expect(iOSIcon.icon == androidIcon.icon, kIsWeb ? isTrue : isFalse);
      expect(linuxIcon.icon == androidIcon.icon, isTrue);
      expect(macOSIcon.icon == androidIcon.icon, kIsWeb ? isTrue : isFalse);
      expect(macOSIcon.icon == iOSIcon.icon, isTrue);
      expect(windowsIcon.icon == androidIcon.icon, isTrue);
    });

    testWidgets('BackButton color', (WidgetTester tester) async {
      await tester.pumpWidget(
        const MaterialApp(
          home: Material(child: BackButton(color: Colors.red)),
        ),
      );

      final RichText iconText = tester.firstWidget(
        find.descendant(of: find.byType(BackButton), matching: find.byType(RichText)),
      );
      expect(iconText.text.style!.color, Colors.red);
    });

    testWidgets('BackButton color with ButtonStyle', (WidgetTester tester) async {
      await tester.pumpWidget(
        const MaterialApp(
          home: Material(
            child: BackButton(
              style: ButtonStyle(iconColor: MaterialStatePropertyAll<Color>(Colors.red)),
            ),
          ),
        ),
      );

      final RichText iconText = tester.firstWidget(
        find.descendant(of: find.byType(BackButton), matching: find.byType(RichText)),
      );
      expect(iconText.text.style!.color, Colors.red);
    });

    testWidgets('BackButton.style.iconColor parameter overrides BackButton.color', (
      WidgetTester tester,
    ) async {
      await tester.pumpWidget(
        const MaterialApp(
          home: Material(
            child: BackButton(
              color: Colors.green,
              style: ButtonStyle(iconColor: MaterialStatePropertyAll<Color>(Colors.red)),
            ),
          ),
        ),
      );

      final RichText iconText = tester.firstWidget(
        find.descendant(of: find.byType(BackButton), matching: find.byType(RichText)),
      );

      expect(iconText.text.style!.color, Colors.red);
    });

    testWidgets('BackButton semantics', (WidgetTester tester) async {
      final SemanticsHandle handle = tester.ensureSemantics();
      await tester.pumpWidget(
        MaterialApp(
          home: const Material(child: Text('Home')),
          routes: <String, WidgetBuilder>{
            '/next': (BuildContext context) {
              return const Material(child: Center(child: BackButton()));
            },
          },
        ),
      );

      tester.state<NavigatorState>(find.byType(Navigator)).pushNamed('/next');

      await tester.pumpAndSettle();
      final String? expectedLabel;
      switch (defaultTargetPlatform) {
        case TargetPlatform.android:
          expectedLabel = 'Back';
        case TargetPlatform.fuchsia:
        case TargetPlatform.iOS:
        case TargetPlatform.linux:
        case TargetPlatform.macOS:
        case TargetPlatform.windows:
          expectedLabel = null;
      }
      expect(
        tester.getSemantics(find.byType(BackButton)),
        matchesSemantics(
          tooltip: 'Back',
          label: expectedLabel,
          isButton: true,
          hasEnabledState: true,
          isEnabled: true,
          hasTapAction: true,
          hasFocusAction: defaultTargetPlatform != TargetPlatform.iOS,
          isFocusable: true,
        ),
      );
      handle.dispose();
    }, variant: TargetPlatformVariant.all());
  });

  group('CloseButton', () {
    testWidgets('CloseButton semantics', (WidgetTester tester) async {
      final SemanticsHandle handle = tester.ensureSemantics();
      await tester.pumpWidget(
        MaterialApp(
          home: const Material(child: Text('Home')),
          routes: <String, WidgetBuilder>{
            '/next': (BuildContext context) {
              return const Material(child: Center(child: CloseButton()));
            },
          },
        ),
      );

      tester.state<NavigatorState>(find.byType(Navigator)).pushNamed('/next');

      await tester.pumpAndSettle();
      final String? expectedLabel;
      switch (defaultTargetPlatform) {
        case TargetPlatform.android:
          expectedLabel = 'Close';
        case TargetPlatform.fuchsia:
        case TargetPlatform.iOS:
        case TargetPlatform.linux:
        case TargetPlatform.macOS:
        case TargetPlatform.windows:
          expectedLabel = null;
      }
      expect(
        tester.getSemantics(find.byType(CloseButton)),
        matchesSemantics(
          tooltip: 'Close',
          label: expectedLabel,
          isButton: true,
          hasEnabledState: true,
          isEnabled: true,
          hasTapAction: true,
          hasFocusAction: defaultTargetPlatform != TargetPlatform.iOS,
          isFocusable: true,
        ),
      );
      handle.dispose();
    }, variant: TargetPlatformVariant.all());

    testWidgets('CloseButton color', (WidgetTester tester) async {
      await tester.pumpWidget(
        const MaterialApp(
          home: Material(child: CloseButton(color: Colors.red)),
        ),
      );

      final RichText iconText = tester.firstWidget(
        find.descendant(of: find.byType(CloseButton), matching: find.byType(RichText)),
      );
      expect(iconText.text.style!.color, Colors.red);
    });

    testWidgets('CloseButton color with ButtonStyle', (WidgetTester tester) async {
      await tester.pumpWidget(
        const MaterialApp(
          home: Material(
            child: CloseButton(
              style: ButtonStyle(iconColor: MaterialStatePropertyAll<Color>(Colors.red)),
            ),
          ),
        ),
      );

      final RichText iconText = tester.firstWidget(
        find.descendant(of: find.byType(CloseButton), matching: find.byType(RichText)),
      );
      expect(iconText.text.style!.color, Colors.red);
    });

    testWidgets('CloseButton.style.iconColor parameter overrides CloseButton.color', (
      WidgetTester tester,
    ) async {
      await tester.pumpWidget(
        const MaterialApp(
          home: Material(
            child: CloseButton(
              color: Colors.green,
              style: ButtonStyle(iconColor: MaterialStatePropertyAll<Color>(Colors.red)),
            ),
          ),
        ),
      );

      final RichText iconText = tester.firstWidget(
        find.descendant(of: find.byType(CloseButton), matching: find.byType(RichText)),
      );

      expect(iconText.text.style!.color, Colors.red);
    });

    testWidgets('CloseButton onPressed overrides default pop behavior', (
      WidgetTester tester,
    ) async {
      bool customCallbackWasCalled = false;
      await tester.pumpWidget(
        MaterialApp(
          home: const Material(child: Text('Home')),
          routes: <String, WidgetBuilder>{
            '/next': (BuildContext context) {
              return Material(
                child: Center(child: CloseButton(onPressed: () => customCallbackWasCalled = true)),
              );
            },
          },
        ),
      );

      tester.state<NavigatorState>(find.byType(Navigator)).pushNamed('/next');

      await tester.pumpAndSettle();
      expect(find.text('Home'), findsNothing); // Start off on the second page.
      expect(customCallbackWasCalled, false); // customCallbackWasCalled should still be false.
      await tester.tap(find.byType(CloseButton));

      await tester.pumpAndSettle();

      // We're still on the second page.
      expect(find.text('Home'), findsNothing);
      // The custom callback is called, setting customCallbackWasCalled to true.
      expect(customCallbackWasCalled, true);
    });
  });

  testWidgets('EndDrawerButton does not crash at zero area', (WidgetTester tester) async {
    await tester.pumpWidget(
      const MaterialApp(
        home: Center(
          child: SizedBox.shrink(child: Scaffold(body: EndDrawerButton())),
        ),
      ),
    );
    expect(tester.getSize(find.byType(EndDrawerButton)), Size.zero);
  });

  testWidgets('CloseButton does not crash at zero area', (WidgetTester tester) async {
    await tester.pumpWidget(
      const MaterialApp(
        home: Center(
          child: SizedBox.shrink(child: Scaffold(body: CloseButton())),
        ),
      ),
    );
    expect(tester.getSize(find.byType(CloseButton)), Size.zero);
  });

  testWidgets('BackButton renders at zero area', (WidgetTester tester) async {
    await tester.pumpWidget(
      const MaterialApp(
        home: Center(
          child: SizedBox.shrink(child: Scaffold(body: BackButton())),
        ),
      ),
    );
    final Finder backButtonIcon = find.byType(BackButtonIcon);
    expect(tester.getSize(backButtonIcon).isEmpty, isTrue);
  });

  testWidgets('BackButton has expected default mouse cursor on hover', (WidgetTester tester) async {
    await tester.pumpWidget(const MaterialApp(home: Material(child: BackButton())));

    final TestGesture gesture = await tester.createGesture(kind: PointerDeviceKind.mouse);
    await gesture.addPointer(location: const Offset(1000, 1000));
    addTearDown(gesture.removePointer);

    expect(
      RendererBinding.instance.mouseTracker.debugDeviceActiveCursor(1),
      SystemMouseCursors.basic,
    );
    await gesture.moveTo(tester.getCenter(find.byType(BackButton)));
    await tester.pump();

    expect(
      RendererBinding.instance.mouseTracker.debugDeviceActiveCursor(1),
      kIsWeb ? SystemMouseCursors.click : SystemMouseCursors.basic,
    );
  });

  testWidgets('CloseButton has expected default mouse cursor on hover', (
    WidgetTester tester,
  ) async {
    await tester.pumpWidget(const MaterialApp(home: Material(child: CloseButton())));

    final TestGesture gesture = await tester.createGesture(kind: PointerDeviceKind.mouse);
    await gesture.addPointer(location: const Offset(1000, 1000));
    addTearDown(gesture.removePointer);

    expect(
      RendererBinding.instance.mouseTracker.debugDeviceActiveCursor(1),
      SystemMouseCursors.basic,
    );
    await gesture.moveTo(tester.getCenter(find.byType(CloseButton)));
    await tester.pump();

    expect(
      RendererBinding.instance.mouseTracker.debugDeviceActiveCursor(1),
      kIsWeb ? SystemMouseCursors.click : SystemMouseCursors.basic,
    );
  });

  testWidgets('BackButton has expected mouse cursor when explicitly configured', (
    WidgetTester tester,
  ) async {
    await tester.pumpWidget(
      MaterialApp(
        home: Material(
          child: BackButton(
            style: ButtonStyle(
              mouseCursor: WidgetStateProperty.all<MouseCursor>(SystemMouseCursors.cell),
            ),
          ),
        ),
      ),
    );

    final TestGesture gesture = await tester.createGesture(kind: PointerDeviceKind.mouse);
    await gesture.addPointer(location: tester.getCenter(find.byType(BackButton)));
    addTearDown(gesture.removePointer);

    expect(
      RendererBinding.instance.mouseTracker.debugDeviceActiveCursor(1),
      SystemMouseCursors.cell,
    );
  });

  testWidgets('CloseButton has expected mouse cursor when explicitly configured', (
    WidgetTester tester,
  ) async {
    await tester.pumpWidget(
      MaterialApp(
        home: Material(
          child: CloseButton(
            style: ButtonStyle(
              mouseCursor: WidgetStateProperty.all<MouseCursor>(SystemMouseCursors.cell),
            ),
          ),
        ),
      ),
    );

    final TestGesture gesture = await tester.createGesture(kind: PointerDeviceKind.mouse);
    await gesture.addPointer(location: tester.getCenter(find.byType(CloseButton)));
    addTearDown(gesture.removePointer);

    expect(
      RendererBinding.instance.mouseTracker.debugDeviceActiveCursor(1),
      SystemMouseCursors.cell,
    );
  });
}