flutter/packages/flutter/test/widgets/animated_container_test.dart

// Copyright 2015 The Chromium 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_test/flutter_test.dart';
import 'package:flutter/rendering.dart';
import 'package:flutter/widgets.dart';

void main() {
  testWidgets('AnimatedContainer control test', (WidgetTester tester) async {
    GlobalKey key = new GlobalKey();

    BoxDecoration decorationA = new BoxDecoration(
      backgroundColor: new Color(0xFF00FF00)
    );

    BoxDecoration decorationB = new BoxDecoration(
      backgroundColor: new Color(0xFF0000FF)
    );

    BoxDecoration actualDecoration;

    await tester.pumpWidget(
      new AnimatedContainer(
        key: key,
        duration: const Duration(milliseconds: 200),
        decoration: decorationA
      )
    );

    RenderDecoratedBox box = key.currentContext.findRenderObject();
    actualDecoration = box.decoration;
    expect(actualDecoration.backgroundColor, equals(decorationA.backgroundColor));

    await tester.pumpWidget(
      new AnimatedContainer(
        key: key,
        duration: const Duration(milliseconds: 200),
        decoration: decorationB
      )
    );

    expect(key.currentContext.findRenderObject(), equals(box));
    actualDecoration = box.decoration;
    expect(actualDecoration.backgroundColor, equals(decorationA.backgroundColor));

    await tester.pump(const Duration(seconds: 1));

    actualDecoration = box.decoration;
    expect(actualDecoration.backgroundColor, equals(decorationB.backgroundColor));
  });

  testWidgets('AnimatedContainer overanimate test', (WidgetTester tester) async {
    await tester.pumpWidget(
      new AnimatedContainer(
        duration: const Duration(milliseconds: 200),
        decoration: new BoxDecoration(
          backgroundColor: new Color(0xFF00FF00)
        )
      )
    );
    expect(tester.binding.transientCallbackCount, 0);
    await tester.pump(new Duration(seconds: 1));
    expect(tester.binding.transientCallbackCount, 0);
    await tester.pumpWidget(
      new AnimatedContainer(
        duration: const Duration(milliseconds: 200),
        decoration: new BoxDecoration(
          backgroundColor: new Color(0xFF00FF00)
        )
      )
    );
    expect(tester.binding.transientCallbackCount, 0);
    await tester.pump(new Duration(seconds: 1));
    expect(tester.binding.transientCallbackCount, 0);
    await tester.pumpWidget(
      new AnimatedContainer(
        duration: const Duration(milliseconds: 200),
        decoration: new BoxDecoration(
          backgroundColor: new Color(0xFF0000FF)
        )
      )
    );
    expect(tester.binding.transientCallbackCount, 1); // this is the only time an animation should have started!
    await tester.pump(new Duration(seconds: 1));
    expect(tester.binding.transientCallbackCount, 0);
    await tester.pumpWidget(
      new AnimatedContainer(
        duration: const Duration(milliseconds: 200),
        decoration: new BoxDecoration(
          backgroundColor: new Color(0xFF0000FF)
        )
      )
    );
    expect(tester.binding.transientCallbackCount, 0);
  });

  testWidgets('Animation rerun', (WidgetTester tester) async {
    await tester.pumpWidget(
      new Center(
        child: new AnimatedContainer(
          duration: const Duration(milliseconds: 200),
          width: 100.0,
          height: 100.0,
          child: new Text('X')
        )
      )
    );

    await tester.pump();
    await tester.pump(new Duration(milliseconds: 100));

    RenderBox text = tester.renderObject(find.text('X'));
    expect(text.size.width, equals(100.0));
    expect(text.size.height, equals(100.0));

    await tester.pump(new Duration(milliseconds: 1000));

    await tester.pumpWidget(
      new Center(
        child: new AnimatedContainer(
          duration: const Duration(milliseconds: 200),
          width: 200.0,
          height: 200.0,
          child: new Text('X')
        )
      )
    );
    await tester.pump();
    await tester.pump(new Duration(milliseconds: 100));

    text = tester.renderObject(find.text('X'));
    expect(text.size.width, greaterThan(110.0));
    expect(text.size.width, lessThan(190.0));
    expect(text.size.height, greaterThan(110.0));
    expect(text.size.height, lessThan(190.0));

    await tester.pump(new Duration(milliseconds: 1000));

    expect(text.size.width, equals(200.0));
    expect(text.size.height, equals(200.0));

    await tester.pumpWidget(
      new Center(
        child: new AnimatedContainer(
          duration: const Duration(milliseconds: 200),
          width: 200.0,
          height: 100.0,
          child: new Text('X')
        )
      )
    );
    await tester.pump();
    await tester.pump(new Duration(milliseconds: 100));

    expect(text.size.width, equals(200.0));
    expect(text.size.height, greaterThan(110.0));
    expect(text.size.height, lessThan(190.0));

    await tester.pump(new Duration(milliseconds: 1000));

    expect(text.size.width, equals(200.0));
    expect(text.size.height, equals(100.0));
  });
}