parent_data_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';
import 'package:test/test.dart';

import 'test_widgets.dart';

class TestParentData {
  TestParentData({ this.top, this.right, this.bottom, this.left });

  final double top;
  final double right;
  final double bottom;
  final double left;
}

void checkTree(WidgetTester tester, List<TestParentData> expectedParentData) {
  MultiChildRenderObjectElement element =
      tester.findElement((Element element) => element is MultiChildRenderObjectElement);
  expect(element, isNotNull);
  expect(element.renderObject is RenderStack, isTrue);
  RenderStack renderObject = element.renderObject;
  try {
    RenderObject child = renderObject.firstChild;
    for (TestParentData expected in expectedParentData) {
      expect(child is RenderDecoratedBox, isTrue);
      RenderDecoratedBox decoratedBox = child;
      expect(decoratedBox.parentData is StackParentData, isTrue);
      StackParentData parentData = decoratedBox.parentData;
      expect(parentData.top, equals(expected.top));
      expect(parentData.right, equals(expected.right));
      expect(parentData.bottom, equals(expected.bottom));
      expect(parentData.left, equals(expected.left));
      StackParentData decoratedBoxParentData = decoratedBox.parentData;
      child = decoratedBoxParentData.nextSibling;
    }
    expect(child, isNull);
  } catch (e) {
    print(renderObject.toStringDeep());
    rethrow;
  }
}

final TestParentData kNonPositioned = new TestParentData();

void main() {
  dynamic cachedException;

  setUp(() {
    assert(cachedException == null);
    debugWidgetsExceptionHandler = (String context, dynamic exception, StackTrace stack) {
      cachedException = exception;
    };
  });

  tearDown(() {
    cachedException = null;
    debugWidgetsExceptionHandler = null;
  });

  test('ParentDataWidget control test', () {
    testWidgets((WidgetTester tester) {

      tester.pumpWidget(
        new Stack(
          children: <Widget>[
            new DecoratedBox(decoration: kBoxDecorationA),
            new Positioned(
              top: 10.0,
              left: 10.0,
              child: new DecoratedBox(decoration: kBoxDecorationB)
            ),
            new DecoratedBox(decoration: kBoxDecorationC),
          ]
        )
      );

      checkTree(tester, <TestParentData>[
        kNonPositioned,
        new TestParentData(top: 10.0, left: 10.0),
        kNonPositioned,
      ]);

      tester.pumpWidget(
        new Stack(
          children: <Widget>[
            new Positioned(
              bottom: 5.0,
              right: 7.0,
              child: new DecoratedBox(decoration: kBoxDecorationA)
            ),
            new Positioned(
              top: 10.0,
              left: 10.0,
              child: new DecoratedBox(decoration: kBoxDecorationB)
            ),
            new DecoratedBox(decoration: kBoxDecorationC),
          ]
        )
      );

      checkTree(tester, <TestParentData>[
        new TestParentData(bottom: 5.0, right: 7.0),
        new TestParentData(top: 10.0, left: 10.0),
        kNonPositioned,
      ]);

      DecoratedBox kDecoratedBoxA = new DecoratedBox(decoration: kBoxDecorationA);
      DecoratedBox kDecoratedBoxB = new DecoratedBox(decoration: kBoxDecorationB);
      DecoratedBox kDecoratedBoxC = new DecoratedBox(decoration: kBoxDecorationC);

      tester.pumpWidget(
        new Stack(
          children: <Widget>[
            new Positioned(
              bottom: 5.0,
              right: 7.0,
              child: kDecoratedBoxA
            ),
            new Positioned(
              top: 10.0,
              left: 10.0,
              child: kDecoratedBoxB
            ),
            kDecoratedBoxC,
          ]
        )
      );

      checkTree(tester, <TestParentData>[
        new TestParentData(bottom: 5.0, right: 7.0),
        new TestParentData(top: 10.0, left: 10.0),
        kNonPositioned,
      ]);

      tester.pumpWidget(
        new Stack(
          children: <Widget>[
            new Positioned(
              bottom: 6.0,
              right: 8.0,
              child: kDecoratedBoxA
            ),
            new Positioned(
              left: 10.0,
              right: 10.0,
              child: kDecoratedBoxB
            ),
            kDecoratedBoxC,
          ]
        )
      );

      checkTree(tester, <TestParentData>[
        new TestParentData(bottom: 6.0, right: 8.0),
        new TestParentData(left: 10.0, right: 10.0),
        kNonPositioned,
      ]);

      tester.pumpWidget(
        new Stack(
          children: <Widget>[
            kDecoratedBoxA,
            new Positioned(
              left: 11.0,
              right: 12.0,
              child: new Container(child: kDecoratedBoxB)
            ),
            kDecoratedBoxC,
          ]
        )
      );

      checkTree(tester, <TestParentData>[
        kNonPositioned,
        new TestParentData(left: 11.0, right: 12.0),
        kNonPositioned,
      ]);

      tester.pumpWidget(
        new Stack(
          children: <Widget>[
            kDecoratedBoxA,
            new Positioned(
              right: 10.0,
              child: new Container(child: kDecoratedBoxB)
            ),
            new Container(
              child: new Positioned(
                top: 8.0,
                child: kDecoratedBoxC
              )
            )
          ]
        )
      );

      checkTree(tester, <TestParentData>[
        kNonPositioned,
        new TestParentData(right: 10.0),
        new TestParentData(top: 8.0),
      ]);

      tester.pumpWidget(
        new Stack(
          children: <Widget>[
            new Positioned(
              right: 10.0,
              child: new FlipWidget(left: kDecoratedBoxA, right: kDecoratedBoxB)
            ),
          ]
        )
      );

      checkTree(tester, <TestParentData>[
        new TestParentData(right: 10.0),
      ]);

      flipStatefulWidget(tester);
      tester.pump();

      checkTree(tester, <TestParentData>[
        new TestParentData(right: 10.0),
      ]);

      tester.pumpWidget(
        new Stack(
          children: <Widget>[
            new Positioned(
              top: 7.0,
              child: new FlipWidget(left: kDecoratedBoxA, right: kDecoratedBoxB)
            ),
          ]
        )
      );

      checkTree(tester, <TestParentData>[
        new TestParentData(top: 7.0),
      ]);

      flipStatefulWidget(tester);
      tester.pump();

      checkTree(tester, <TestParentData>[
        new TestParentData(top: 7.0),
      ]);

      tester.pumpWidget(
        new Stack()
      );

      checkTree(tester, <TestParentData>[]);
    });
  });

  test('ParentDataWidget conflicting data', () {
    testWidgets((WidgetTester tester) {
      expect(cachedException, isNull);

      tester.pumpWidget(
        new Stack(
          children: <Widget>[
            new Positioned(
              top: 5.0,
              bottom: 8.0,
              child: new Positioned(
                top: 6.0,
                left: 7.0,
                child: new DecoratedBox(decoration: kBoxDecorationB)
              )
            )
          ]
        )
      );

      expect(cachedException, isNotNull);
      cachedException = null;

      tester.pumpWidget(new Stack());

      checkTree(tester, <TestParentData>[]);
      expect(cachedException, isNull);

      tester.pumpWidget(
        new Container(
          child: new Flex(
            children: <Widget>[
              new Positioned(
                top: 6.0,
                left: 7.0,
                child: new DecoratedBox(decoration: kBoxDecorationB)
              )
            ]
          )
        )
      );

      expect(cachedException, isNotNull);
      cachedException = null;

      tester.pumpWidget(
        new Stack()
      );

      checkTree(tester, <TestParentData>[]);
    });
  });

  test('ParentDataWidget interacts with global keys', () {
    testWidgets((WidgetTester tester) {
      GlobalKey key = new GlobalKey();

      tester.pumpWidget(
        new Stack(
          children: <Widget>[
            new Positioned(
              top: 10.0,
              left: 10.0,
              child: new DecoratedBox(key: key, decoration: kBoxDecorationA)
            )
          ]
        )
      );

      checkTree(tester, <TestParentData>[
        new TestParentData(top: 10.0, left: 10.0),
      ]);

      tester.pumpWidget(
        new Stack(
          children: <Widget>[
            new Positioned(
              top: 10.0,
              left: 10.0,
              child: new DecoratedBox(
                decoration: kBoxDecorationB,
                child: new DecoratedBox(key: key, decoration: kBoxDecorationA)
              )
            )
          ]
        )
      );

      checkTree(tester, <TestParentData>[
        new TestParentData(top: 10.0, left: 10.0),
      ]);

      tester.pumpWidget(
        new Stack(
          children: <Widget>[
            new Positioned(
              top: 10.0,
              left: 10.0,
              child: new DecoratedBox(key: key, decoration: kBoxDecorationA)
            )
          ]
        )
      );

      checkTree(tester, <TestParentData>[
        new TestParentData(top: 10.0, left: 10.0),
      ]);
    });
  });
}