flutter/packages/unit/test/widget/multichild_test.dart

import 'package:sky/rendering.dart';
import 'package:sky/widgets.dart';
import 'package:test/test.dart';

import 'test_widgets.dart';
import 'widget_tester.dart';

void checkTree(WidgetTester tester, List<BoxDecoration> expectedDecorations) {
  MultiChildRenderObjectElement element =
      tester.findElement((element) => element is MultiChildRenderObjectElement);
  expect(element, isNotNull);
  expect(element.renderObject is RenderStack, isTrue);
  RenderStack renderObject = element.renderObject;
  try {
    RenderObject child = renderObject.firstChild;
    for (BoxDecoration decoration in expectedDecorations) {
      expect(child is RenderDecoratedBox, isTrue);
      RenderDecoratedBox decoratedBox = child;
      expect(decoratedBox.decoration, equals(decoration));
      child = decoratedBox.parentData.nextSibling;
    }
    expect(child, isNull);
  } catch (e) {
    print(renderObject.toStringDeep());
    rethrow;
  }
}

void main() {
  test('MultiChildRenderObjectElement control test', () {
    WidgetTester tester = new WidgetTester();

    tester.pumpFrame(
      new Stack([
        new DecoratedBox(decoration: kBoxDecorationA),
        new DecoratedBox(decoration: kBoxDecorationB),
        new DecoratedBox(decoration: kBoxDecorationC),
      ])
    );

    checkTree(tester, [kBoxDecorationA, kBoxDecorationB, kBoxDecorationC]);

    tester.pumpFrame(
      new Stack([
        new DecoratedBox(decoration: kBoxDecorationA),
        new DecoratedBox(decoration: kBoxDecorationC),
      ])
    );

    checkTree(tester, [kBoxDecorationA, kBoxDecorationC]);

    tester.pumpFrame(
      new Stack([
        new DecoratedBox(decoration: kBoxDecorationA),
        new DecoratedBox(key: new Key('b'), decoration: kBoxDecorationB),
        new DecoratedBox(decoration: kBoxDecorationC),
      ])
    );

    checkTree(tester, [kBoxDecorationA, kBoxDecorationB, kBoxDecorationC]);

    tester.pumpFrame(
      new Stack([
        new DecoratedBox(key: new Key('b'), decoration: kBoxDecorationB),
        new DecoratedBox(decoration: kBoxDecorationC),
        new DecoratedBox(key: new Key('a'), decoration: kBoxDecorationA),
      ])
    );

    checkTree(tester, [kBoxDecorationB, kBoxDecorationC, kBoxDecorationA]);

    tester.pumpFrame(
      new Stack([
        new DecoratedBox(key: new Key('a'), decoration: kBoxDecorationA),
        new DecoratedBox(decoration: kBoxDecorationC),
        new DecoratedBox(key: new Key('b'), decoration: kBoxDecorationB),
      ])
    );

    checkTree(tester, [kBoxDecorationA, kBoxDecorationC, kBoxDecorationB]);

    tester.pumpFrame(
      new Stack([
        new DecoratedBox(decoration: kBoxDecorationC),
      ])
    );

    checkTree(tester, [kBoxDecorationC]);

    tester.pumpFrame(
      new Stack([])
    );

    checkTree(tester, []);
  });

  test('MultiChildRenderObjectElement with stateless components', () {
    WidgetTester tester = new WidgetTester();

    tester.pumpFrame(
      new Stack([
        new DecoratedBox(decoration: kBoxDecorationA),
        new DecoratedBox(decoration: kBoxDecorationB),
        new DecoratedBox(decoration: kBoxDecorationC),
      ])
    );

    checkTree(tester, [kBoxDecorationA, kBoxDecorationB, kBoxDecorationC]);

    tester.pumpFrame(
      new Stack([
        new DecoratedBox(decoration: kBoxDecorationA),
        new Container(
          child: new DecoratedBox(decoration: kBoxDecorationB)
        ),
        new DecoratedBox(decoration: kBoxDecorationC),
      ])
    );

    checkTree(tester, [kBoxDecorationA, kBoxDecorationB, kBoxDecorationC]);

    tester.pumpFrame(
      new Stack([
        new DecoratedBox(decoration: kBoxDecorationA),
        new Container(
          child: new Container(
            child: new DecoratedBox(decoration: kBoxDecorationB)
          )
        ),
        new DecoratedBox(decoration: kBoxDecorationC),
      ])
    );

    checkTree(tester, [kBoxDecorationA, kBoxDecorationB, kBoxDecorationC]);

    tester.pumpFrame(
      new Stack([
        new Container(
          child: new Container(
            child: new DecoratedBox(decoration: kBoxDecorationB)
          )
        ),
        new Container(
          child: new DecoratedBox(decoration: kBoxDecorationA)
        ),
        new DecoratedBox(decoration: kBoxDecorationC),
      ])
    );

    checkTree(tester, [kBoxDecorationB, kBoxDecorationA, kBoxDecorationC]);

    tester.pumpFrame(
      new Stack([
        new Container(
          child: new DecoratedBox(decoration: kBoxDecorationB)
        ),
        new Container(
          child: new DecoratedBox(decoration: kBoxDecorationA)
        ),
        new DecoratedBox(decoration: kBoxDecorationC),
      ])
    );

    checkTree(tester, [kBoxDecorationB, kBoxDecorationA, kBoxDecorationC]);

    tester.pumpFrame(
      new Stack([
        new Container(
          key: new Key('b'),
          child: new DecoratedBox(decoration: kBoxDecorationB)
        ),
        new Container(
          key: new Key('a'),
          child: new DecoratedBox(decoration: kBoxDecorationA)
        ),
      ])
    );

    checkTree(tester, [kBoxDecorationB, kBoxDecorationA]);

    tester.pumpFrame(
      new Stack([
        new Container(
          key: new Key('a'),
          child: new DecoratedBox(decoration: kBoxDecorationA)
        ),
        new Container(
          key: new Key('b'),
          child: new DecoratedBox(decoration: kBoxDecorationB)
        ),
      ])
    );

    checkTree(tester, [kBoxDecorationA, kBoxDecorationB]);

    tester.pumpFrame(
      new Stack([ ])
    );

    checkTree(tester, []);
  });

  test('MultiChildRenderObjectElement with stateful components', () {
    WidgetTester tester = new WidgetTester();

    tester.pumpFrame(
      new Stack([
        new DecoratedBox(decoration: kBoxDecorationA),
        new DecoratedBox(decoration: kBoxDecorationB),
      ])
    );

    checkTree(tester, [kBoxDecorationA, kBoxDecorationB]);

    tester.pumpFrame(
      new Stack([
        new FlipComponent(
          left: new DecoratedBox(decoration: kBoxDecorationA),
          right: new DecoratedBox(decoration: kBoxDecorationB)
        ),
        new DecoratedBox(decoration: kBoxDecorationC),
      ])
    );

    checkTree(tester, [kBoxDecorationA, kBoxDecorationC]);

    flipStatefulComponent(tester);
    tester.pumpFrameWithoutChange();

    checkTree(tester, [kBoxDecorationB, kBoxDecorationC]);

    tester.pumpFrame(
      new Stack([
        new FlipComponent(
          left: new DecoratedBox(decoration: kBoxDecorationA),
          right: new DecoratedBox(decoration: kBoxDecorationB)
        ),
      ])
    );

    checkTree(tester, [kBoxDecorationB]);

    flipStatefulComponent(tester);
    tester.pumpFrameWithoutChange();

    checkTree(tester, [kBoxDecorationA]);

    tester.pumpFrame(
      new Stack([
        new FlipComponent(
          key: new Key('flip'),
          left: new DecoratedBox(decoration: kBoxDecorationA),
          right: new DecoratedBox(decoration: kBoxDecorationB)
        ),
      ])
    );

    tester.pumpFrame(
      new Stack([
        new DecoratedBox(key: new Key('c'), decoration: kBoxDecorationC),
        new FlipComponent(
          key: new Key('flip'),
          left: new DecoratedBox(decoration: kBoxDecorationA),
          right: new DecoratedBox(decoration: kBoxDecorationB)
        ),
      ])
    );

    checkTree(tester, [kBoxDecorationC, kBoxDecorationA]);

    flipStatefulComponent(tester);
    tester.pumpFrameWithoutChange();

    checkTree(tester, [kBoxDecorationC, kBoxDecorationB]);

    tester.pumpFrame(
      new Stack([
        new FlipComponent(
          key: new Key('flip'),
          left: new DecoratedBox(decoration: kBoxDecorationA),
          right: new DecoratedBox(decoration: kBoxDecorationB)
        ),
        new DecoratedBox(key: new Key('c'), decoration: kBoxDecorationC),
      ])
    );

    checkTree(tester, [kBoxDecorationB, kBoxDecorationC]);

  });
}