examples/api/test/material/scrollbar/scrollbar.0_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/material.dart';
import 'package:flutter_api_samples/material/scrollbar/scrollbar.0.dart'
    as example;
import 'package:flutter_test/flutter_test.dart';

void main() {
  testWidgets(
    'Scrollbar.0 works well on all platforms',
    (WidgetTester tester) async {
      await tester.pumpWidget(const example.ScrollbarExampleApp());

      final Finder buttonFinder = find.byType(Scrollbar);
      await tester.drag(buttonFinder.last, const Offset(0, 100.0));

      expect(tester.takeException(), isNull);
    },
    variant: TargetPlatformVariant.all(),
  );

  testWidgets('The scrollbar should be painted when the user scrolls', (
    WidgetTester tester,
  ) async {
    await tester.pumpWidget(const example.ScrollbarExampleApp());
    await tester.pump();
    await tester.pump(
      const Duration(milliseconds: 10),
    ); // Wait for the thumb to start appearing.

    expect(find.text('item 0'), findsOne);
    expect(find.text('item 9'), findsNothing);
    expect(find.byType(Scrollbar), isNot(paints..rect()));

    await tester.fling(
      find.byType(Scrollbar).last,
      const Offset(0, -300),
      10.0,
    );

    expect(find.text('item 0'), findsNothing);
    expect(find.text('item 9'), findsOne);
    expect(find.byType(Scrollbar).last, paints..rect());
  });
}