packages/flutter/test/widgets/scrollable_helpers_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 'package:flutter/foundation.dart';
import 'package:flutter/material.dart';
import 'package:flutter/services.dart';
import 'package:flutter_test/flutter_test.dart';

final LogicalKeyboardKey modifierKey = defaultTargetPlatform == TargetPlatform.macOS
  ? LogicalKeyboardKey.metaLeft
  : LogicalKeyboardKey.controlLeft;

void main() {
  group('ScrollableDetails', (){
    final ScrollController controller = ScrollController();
    test('copyWith / == / hashCode', () {
      final ScrollableDetails details = ScrollableDetails(
        direction: AxisDirection.down,
        controller: controller,
        physics: const AlwaysScrollableScrollPhysics(),
        decorationClipBehavior: Clip.hardEdge,
      );
      ScrollableDetails copiedDetails = details.copyWith();
      expect(details, copiedDetails);
      expect(details.hashCode, copiedDetails.hashCode);

      copiedDetails = details.copyWith(
        direction: AxisDirection.left,
        physics: const ClampingScrollPhysics(),
        decorationClipBehavior: Clip.none,
      );
      expect(
        copiedDetails,
        ScrollableDetails(
          direction: AxisDirection.left,
          controller: controller,
          physics: const ClampingScrollPhysics(),
          decorationClipBehavior: Clip.none,
        ),
      );
    });

    test('toString', (){
      const ScrollableDetails bareDetails = ScrollableDetails(
        direction: AxisDirection.right,
      );
      expect(
        bareDetails.toString(),
        equalsIgnoringHashCodes(
          'ScrollableDetails#00000(axisDirection: AxisDirection.right)'
        ),
      );
      final ScrollableDetails fullDetails = ScrollableDetails(
        direction: AxisDirection.down,
        controller: controller,
        physics: const AlwaysScrollableScrollPhysics(),
        decorationClipBehavior: Clip.hardEdge,
      );
      expect(
        fullDetails.toString(),
        equalsIgnoringHashCodes(
          'ScrollableDetails#00000('
          'axisDirection: AxisDirection.down, '
          'scroll controller: ScrollController#00000(no clients), '
          'scroll physics: AlwaysScrollableScrollPhysics, '
          'decorationClipBehavior: Clip.hardEdge)'
        ),
      );
    });

    test('deprecated clipBehavior is backwards compatible', (){
      const ScrollableDetails deprecatedClip = ScrollableDetails(
        direction: AxisDirection.right,
        clipBehavior: Clip.hardEdge,
      );
      expect(deprecatedClip.clipBehavior, Clip.hardEdge);
      expect(deprecatedClip.decorationClipBehavior, Clip.hardEdge);

      const ScrollableDetails newClip = ScrollableDetails(
        direction: AxisDirection.right,
        decorationClipBehavior: Clip.hardEdge,
      );
      expect(newClip.clipBehavior, Clip.hardEdge);
      expect(newClip.decorationClipBehavior, Clip.hardEdge);
    });
  });

  testWidgets("Keyboard scrolling doesn't happen if scroll physics are set to NeverScrollableScrollPhysics", (WidgetTester tester) async {
    final ScrollController controller = ScrollController();
    await tester.pumpWidget(
      MaterialApp(
        theme: ThemeData(platform: TargetPlatform.fuchsia),
        home: CustomScrollView(
          controller: controller,
          physics: const NeverScrollableScrollPhysics(),
          slivers: List<Widget>.generate(
            20,
            (int index) {
              return SliverToBoxAdapter(
                child: Focus(
                  autofocus: index == 0,
                  child: SizedBox(
                    key: ValueKey<String>('Box $index'),
                    height: 50.0,
                  ),
                ),
              );
            },
          ),
        ),
      ),
    );

    await tester.pumpAndSettle();
    expect(controller.position.pixels, equals(0.0));
    expect(
      tester.getRect(find.byKey(const ValueKey<String>('Box 0'), skipOffstage: false)),
      equals(const Rect.fromLTRB(0.0, 0.0, 800.0, 50.0)),
    );
    await tester.sendKeyDownEvent(modifierKey);
    await tester.sendKeyEvent(LogicalKeyboardKey.arrowDown);
    await tester.sendKeyUpEvent(modifierKey);
    await tester.pumpAndSettle();
    expect(controller.position.pixels, equals(0.0));
    expect(
      tester.getRect(find.byKey(const ValueKey<String>('Box 0'), skipOffstage: false)),
      equals(const Rect.fromLTRB(0.0, 0.0, 800.0, 50.0)),
    );
    await tester.sendKeyDownEvent(modifierKey);
    await tester.sendKeyEvent(LogicalKeyboardKey.arrowUp);
    await tester.sendKeyUpEvent(modifierKey);
    await tester.pumpAndSettle();
    expect(controller.position.pixels, equals(0.0));
    expect(
      tester.getRect(find.byKey(const ValueKey<String>('Box 0'), skipOffstage: false)),
      equals(const Rect.fromLTRB(0.0, 0.0, 800.0, 50.0)),
    );
    await tester.sendKeyEvent(LogicalKeyboardKey.pageDown);
    await tester.pumpAndSettle();
    expect(controller.position.pixels, equals(0.0));
    expect(
      tester.getRect(find.byKey(const ValueKey<String>('Box 0'), skipOffstage: false)),
      equals(const Rect.fromLTRB(0.0, 0.0, 800.0, 50.0)),
    );
    await tester.sendKeyEvent(LogicalKeyboardKey.pageUp);
    await tester.pumpAndSettle();
    expect(controller.position.pixels, equals(0.0));
    expect(
      tester.getRect(find.byKey(const ValueKey<String>('Box 0'), skipOffstage: false)),
      equals(const Rect.fromLTRB(0.0, 0.0, 800.0, 50.0)),
    );
  }, variant: KeySimulatorTransitModeVariant.all());

  testWidgets('Vertical scrollables are scrolled when activated via keyboard.', (WidgetTester tester) async {
    final ScrollController controller = ScrollController();
    await tester.pumpWidget(
      MaterialApp(
        theme: ThemeData(platform: TargetPlatform.fuchsia),
        home: CustomScrollView(
          controller: controller,
          slivers: List<Widget>.generate(
            20,
            (int index) {
              return SliverToBoxAdapter(
                child: Focus(
                  autofocus: index == 0,
                  child: SizedBox(
                    key: ValueKey<String>('Box $index'),
                    height: 50.0,
                  ),
                ),
              );
            },
          ),
        ),
      ),
    );

    await tester.pumpAndSettle();
    expect(controller.position.pixels, equals(0.0));
    expect(
      tester.getRect(find.byKey(const ValueKey<String>('Box 0'), skipOffstage: false)),
      equals(const Rect.fromLTRB(0.0, 0.0, 800.0, 50.0)),
    );
    // We exclude the modifier keys here for web testing since default web shortcuts
    // do not use a modifier key with arrow keys for ScrollActions.
    if (!kIsWeb) {
      await tester.sendKeyDownEvent(modifierKey);
    }
    await tester.sendKeyEvent(LogicalKeyboardKey.arrowDown);
    if (!kIsWeb) {
      await tester.sendKeyUpEvent(modifierKey);
    }
    await tester.pumpAndSettle();
    expect(
      tester.getRect(find.byKey(const ValueKey<String>('Box 0'), skipOffstage: false)),
      equals(const Rect.fromLTRB(0.0, -50.0, 800.0, 0.0)),
    );
    if (!kIsWeb) {
      await tester.sendKeyDownEvent(modifierKey);
    }
    await tester.sendKeyEvent(LogicalKeyboardKey.arrowUp);
    if (!kIsWeb) {
      await tester.sendKeyUpEvent(modifierKey);
    }
    await tester.pumpAndSettle();
    expect(
      tester.getRect(find.byKey(const ValueKey<String>('Box 0'), skipOffstage: false)),
      equals(const Rect.fromLTRB(0.0, 0.0, 800.0, 50.0)),
    );
    await tester.sendKeyEvent(LogicalKeyboardKey.pageDown);
    await tester.pumpAndSettle();
    expect(
      tester.getRect(find.byKey(const ValueKey<String>('Box 0'), skipOffstage: false)),
      equals(const Rect.fromLTRB(0.0, -400.0, 800.0, -350.0)),
    );
    await tester.sendKeyEvent(LogicalKeyboardKey.pageUp);
    await tester.pumpAndSettle();
    expect(
      tester.getRect(find.byKey(const ValueKey<String>('Box 0'), skipOffstage: false)),
      equals(const Rect.fromLTRB(0.0, 0.0, 800.0, 50.0)),
    );
  }, variant: KeySimulatorTransitModeVariant.all());

  testWidgets('Horizontal scrollables are scrolled when activated via keyboard.', (WidgetTester tester) async {
    final ScrollController controller = ScrollController();
    await tester.pumpWidget(
      MaterialApp(
        theme: ThemeData(platform: TargetPlatform.fuchsia),
        home: CustomScrollView(
          controller: controller,
          scrollDirection: Axis.horizontal,
          slivers: List<Widget>.generate(
            20,
            (int index) {
              return SliverToBoxAdapter(
                child: Focus(
                  autofocus: index == 0,
                  child: SizedBox(
                    key: ValueKey<String>('Box $index'),
                    width: 50.0,
                  ),
                ),
              );
            },
          ),
        ),
      ),
    );

    await tester.pumpAndSettle();
    expect(controller.position.pixels, equals(0.0));
    expect(
      tester.getRect(find.byKey(const ValueKey<String>('Box 0'), skipOffstage: false)),
      equals(const Rect.fromLTRB(0.0, 0.0, 50.0, 600.0)),
    );
    // We exclude the modifier keys here for web testing since default web shortcuts
    // do not use a modifier key with arrow keys for ScrollActions.
    if (!kIsWeb) {
      await tester.sendKeyDownEvent(modifierKey);
    }
    await tester.sendKeyEvent(LogicalKeyboardKey.arrowRight);
    if (!kIsWeb) {
      await tester.sendKeyUpEvent(modifierKey);
    }
    await tester.pumpAndSettle();
    expect(
      tester.getRect(find.byKey(const ValueKey<String>('Box 0'), skipOffstage: false)),
      equals(const Rect.fromLTRB(-50.0, 0.0, 0.0, 600.0)),
    );
    if (!kIsWeb) {
      await tester.sendKeyDownEvent(modifierKey);
    }
    await tester.sendKeyEvent(LogicalKeyboardKey.arrowLeft);
    if (!kIsWeb) {
      await tester.sendKeyUpEvent(modifierKey);
    }
    await tester.pumpAndSettle();
    expect(
      tester.getRect(find.byKey(const ValueKey<String>('Box 0'), skipOffstage: false)),
      equals(const Rect.fromLTRB(0.0, 0.0, 50.0, 600.0)),
    );
  }, variant: KeySimulatorTransitModeVariant.all());

  testWidgets('Horizontal scrollables are scrolled the correct direction in RTL locales.', (WidgetTester tester) async {
    final ScrollController controller = ScrollController();
    await tester.pumpWidget(
      MaterialApp(
        theme: ThemeData(platform: TargetPlatform.fuchsia),
        home: Directionality(
          textDirection: TextDirection.rtl,
          child: CustomScrollView(
            controller: controller,
            scrollDirection: Axis.horizontal,
            slivers: List<Widget>.generate(
              20,
                  (int index) {
                return SliverToBoxAdapter(
                  child: Focus(
                    autofocus: index == 0,
                    child: SizedBox(
                      key: ValueKey<String>('Box $index'),
                      width: 50.0,
                    ),
                  ),
                );
              },
            ),
          ),
        ),
      ),
    );

    await tester.pumpAndSettle();
    expect(controller.position.pixels, equals(0.0));
    expect(
      tester.getRect(find.byKey(const ValueKey<String>('Box 0'), skipOffstage: false)),
      equals(const Rect.fromLTRB(750.0, 0.0, 800.0, 600.0)),
    );
    // We exclude the modifier keys here for web testing since default web shortcuts
    // do not use a modifier key with arrow keys for ScrollActions.
    if (!kIsWeb) {
      await tester.sendKeyDownEvent(modifierKey);
    }
    await tester.sendKeyEvent(LogicalKeyboardKey.arrowLeft);
    if (!kIsWeb) {
      await tester.sendKeyUpEvent(modifierKey);
    }
    await tester.pumpAndSettle();
    expect(
      tester.getRect(find.byKey(const ValueKey<String>('Box 0'), skipOffstage: false)),
      equals(const Rect.fromLTRB(800.0, 0.0, 850.0, 600.0)),
    );
    if (!kIsWeb) {
      await tester.sendKeyDownEvent(modifierKey);
    }
    await tester.sendKeyEvent(LogicalKeyboardKey.arrowRight);
    if (!kIsWeb) {
      await tester.sendKeyUpEvent(modifierKey);
    }
    await tester.pumpAndSettle();
    expect(
      tester.getRect(find.byKey(const ValueKey<String>('Box 0'), skipOffstage: false)),
      equals(const Rect.fromLTRB(750.0, 0.0, 800.0, 600.0)),
    );
  }, variant: KeySimulatorTransitModeVariant.all());

  testWidgets('Reversed vertical scrollables are scrolled when activated via keyboard.', (WidgetTester tester) async {
    final ScrollController controller = ScrollController();
    final FocusNode focusNode = FocusNode(debugLabel: 'SizedBox');
    await tester.pumpWidget(
      MaterialApp(
        theme: ThemeData(platform: TargetPlatform.fuchsia),
        home: CustomScrollView(
          controller: controller,
          reverse: true,
          slivers: List<Widget>.generate(
            20,
            (int index) {
              return SliverToBoxAdapter(
                child: Focus(
                  focusNode: focusNode,
                  child: SizedBox(
                    key: ValueKey<String>('Box $index'),
                    height: 50.0,
                  ),
                ),
              );
            },
          ),
        ),
      ),
    );

    focusNode.requestFocus();
    await tester.pumpAndSettle();
    expect(controller.position.pixels, equals(0.0));
    expect(
      tester.getRect(find.byKey(const ValueKey<String>('Box 0'), skipOffstage: false)),
      equals(const Rect.fromLTRB(0.0, 550.0, 800.0, 600.0)),
    );
    // We exclude the modifier keys here for web testing since default web shortcuts
    // do not use a modifier key with arrow keys for ScrollActions.
    if (!kIsWeb) {
      await tester.sendKeyDownEvent(modifierKey);
    }
    await tester.sendKeyEvent(LogicalKeyboardKey.arrowUp);
    if (!kIsWeb) {
      await tester.sendKeyUpEvent(modifierKey);
    }
    await tester.pumpAndSettle();
    expect(
      tester.getRect(find.byKey(const ValueKey<String>('Box 0'), skipOffstage: false)),
      equals(const Rect.fromLTRB(0.0, 600.0, 800.0, 650.0)),
    );
    if (!kIsWeb) {
      await tester.sendKeyDownEvent(modifierKey);
    }
    await tester.sendKeyEvent(LogicalKeyboardKey.arrowDown);
    if (!kIsWeb) {
      await tester.sendKeyUpEvent(modifierKey);
    }
    await tester.pumpAndSettle();
    expect(
      tester.getRect(find.byKey(const ValueKey<String>('Box 0'), skipOffstage: false)),
      equals(const Rect.fromLTRB(0.0, 550.0, 800.0, 600.0)),
    );
    await tester.sendKeyEvent(LogicalKeyboardKey.pageUp);
    await tester.pumpAndSettle();
    expect(
      tester.getRect(find.byKey(const ValueKey<String>('Box 0'), skipOffstage: false)),
      equals(const Rect.fromLTRB(0.0, 950.0, 800.0, 1000.0)),
    );
    await tester.sendKeyEvent(LogicalKeyboardKey.pageDown);
    await tester.pumpAndSettle();
    expect(
      tester.getRect(find.byKey(const ValueKey<String>('Box 0'), skipOffstage: false)),
      equals(const Rect.fromLTRB(0.0, 550.0, 800.0, 600.0)),
    );
  }, variant: KeySimulatorTransitModeVariant.all());

  testWidgets('Reversed horizontal scrollables are scrolled when activated via keyboard.', (WidgetTester tester) async {
    final ScrollController controller = ScrollController();
    final FocusNode focusNode = FocusNode(debugLabel: 'SizedBox');
    await tester.pumpWidget(
      MaterialApp(
        theme: ThemeData(platform: TargetPlatform.fuchsia),
        home: CustomScrollView(
          controller: controller,
          scrollDirection: Axis.horizontal,
          reverse: true,
          slivers: List<Widget>.generate(
            20,
            (int index) {
              return SliverToBoxAdapter(
                child: Focus(
                  focusNode: focusNode,
                  child: SizedBox(
                    key: ValueKey<String>('Box $index'),
                    width: 50.0,
                  ),
                ),
              );
            },
          ),
        ),
      ),
    );

    focusNode.requestFocus();
    await tester.pumpAndSettle();
    expect(controller.position.pixels, equals(0.0));
    expect(
      tester.getRect(find.byKey(const ValueKey<String>('Box 0'), skipOffstage: false)),
      equals(const Rect.fromLTRB(750.0, 0.0, 800.0, 600.00)),
    );
    // We exclude the modifier keys here for web testing since default web shortcuts
    // do not use a modifier key with arrow keys for ScrollActions.
    if (!kIsWeb) {
      await tester.sendKeyDownEvent(modifierKey);
    }
    await tester.sendKeyEvent(LogicalKeyboardKey.arrowLeft);
    if (!kIsWeb) {
      await tester.sendKeyUpEvent(modifierKey);
    }
    await tester.pumpAndSettle();
    expect(
      tester.getRect(find.byKey(const ValueKey<String>('Box 0'), skipOffstage: false)),
      equals(const Rect.fromLTRB(800.0, 0.0, 850.0, 600.0)),
    );
    if (!kIsWeb) {
      await tester.sendKeyDownEvent(modifierKey);
    }
    await tester.sendKeyEvent(LogicalKeyboardKey.arrowRight);
    if (!kIsWeb) {
      await tester.sendKeyUpEvent(modifierKey);
    }
    await tester.pumpAndSettle();
  }, variant: KeySimulatorTransitModeVariant.all());

  testWidgets('Custom scrollables with a center sliver are scrolled when activated via keyboard.', (WidgetTester tester) async {
    final ScrollController controller = ScrollController();
    final List<String> items = List<String>.generate(20, (int index) => 'Item $index');
    await tester.pumpWidget(
      MaterialApp(
        theme: ThemeData(platform: TargetPlatform.fuchsia),
        home: CustomScrollView(
          controller: controller,
          center: const ValueKey<String>('Center'),
          slivers: items.map<Widget>(
            (String item) {
              return SliverToBoxAdapter(
                key: item == 'Item 10' ? const ValueKey<String>('Center') : null,
                child: Focus(
                  autofocus: item == 'Item 10',
                  child: Container(
                    key: ValueKey<String>(item),
                    alignment: Alignment.center,
                    height: 100,
                    child: Text(item),
                  ),
                ),
              );
            },
          ).toList(),
        ),
      ),
    );

    await tester.pumpAndSettle();
    expect(controller.position.pixels, equals(0.0));
    expect(
      tester.getRect(find.byKey(const ValueKey<String>('Item 10'), skipOffstage: false)),
      equals(const Rect.fromLTRB(0.0, 0.0, 800.0, 100.0)),
    );
    for (int i = 0; i < 10; ++i) {
      // We exclude the modifier keys here for web testing since default web shortcuts
      // do not use a modifier key with arrow keys for ScrollActions.
      if (!kIsWeb) {
        await tester.sendKeyDownEvent(modifierKey);
      }
      await tester.sendKeyEvent(LogicalKeyboardKey.arrowDown);
      if (!kIsWeb) {
        await tester.sendKeyUpEvent(modifierKey);
      }
      await tester.pumpAndSettle();
    }
    // Starts at #10 already, so doesn't work out to 500.0 because it hits bottom.
    expect(controller.position.pixels, equals(400.0));
    expect(
      tester.getRect(find.byKey(const ValueKey<String>('Item 10'), skipOffstage: false)),
      equals(const Rect.fromLTRB(0.0, -400.0, 800.0, -300.0)),
    );
    for (int i = 0; i < 10; ++i) {
      if (!kIsWeb) {
        await tester.sendKeyDownEvent(modifierKey);
      }
      await tester.sendKeyEvent(LogicalKeyboardKey.arrowUp);
      if (!kIsWeb) {
        await tester.sendKeyUpEvent(modifierKey);
      }
      await tester.pumpAndSettle();
    }
    // Goes up two past "center" where it started, so negative.
    expect(controller.position.pixels, equals(-100.0));
    expect(
      tester.getRect(find.byKey(const ValueKey<String>('Item 10'), skipOffstage: false)),
      equals(const Rect.fromLTRB(0.0, 100.0, 800.0, 200.0)),
    );
  }, variant: KeySimulatorTransitModeVariant.all());

  testWidgets('Can scroll using intents only', (WidgetTester tester) async {
    await tester.pumpWidget(
      MaterialApp(
        home: ListView(
          children: const <Widget>[
            SizedBox(height: 600.0, child: Text('The cow as white as milk')),
            SizedBox(height: 600.0, child: Text('The cape as red as blood')),
            SizedBox(height: 600.0, child: Text('The hair as yellow as corn')),
          ],
        ),
      ),
    );
    expect(find.text('The cow as white as milk'), findsOneWidget);
    expect(find.text('The cape as red as blood'), findsNothing);
    expect(find.text('The hair as yellow as corn'), findsNothing);
    Actions.invoke(tester.element(find.byType(SliverList)), const ScrollIntent(direction: AxisDirection.down, type: ScrollIncrementType.page));
    await tester.pump(); // start scroll
    await tester.pump(const Duration(milliseconds: 1000)); // end scroll
    expect(find.text('The cow as white as milk'), findsOneWidget);
    expect(find.text('The cape as red as blood'), findsOneWidget);
    expect(find.text('The hair as yellow as corn'), findsNothing);
    Actions.invoke(tester.element(find.byType(SliverList)), const ScrollIntent(direction: AxisDirection.down, type: ScrollIncrementType.page));
    await tester.pump(); // start scroll
    await tester.pump(const Duration(milliseconds: 1000)); // end scroll
    expect(find.text('The cow as white as milk'), findsNothing);
    expect(find.text('The cape as red as blood'), findsOneWidget);
    expect(find.text('The hair as yellow as corn'), findsOneWidget);
  });
}