image_test.dart

// Copyright 2016 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 'dart:async';
import 'dart:ui' as ui show Image;

import 'package:mojo/core.dart' as core;
import 'package:flutter_test/flutter_test.dart';
import 'package:flutter/services.dart';
import 'package:flutter/rendering.dart';
import 'package:flutter/widgets.dart';
import 'package:test/test.dart';

void main() {
  testWidgets('Verify NetworkImage sets an ObjectKey on its ImageResource if it doesn\'t have a key', (WidgetTester tester) {
    final String testUrl = 'https://foo.bar/baz1.png';
    tester.pumpWidget(
      new NetworkImage(
        scale: 1.0,
        src: testUrl
      )
    );

    ImageResource imageResource = imageCache.load(testUrl, scale: 1.0);
    expect(find.byKey(new ObjectKey(imageResource)), findsOneWidget);
  });

  testWidgets('Verify NetworkImage doesn\'t set an ObjectKey on its ImageResource if it has a key', (WidgetTester tester) {
    final String testUrl = 'https://foo.bar/baz2.png';
    tester.pumpWidget(
      new NetworkImage(
        key: new GlobalKey(),
        scale: 1.0,
        src: testUrl
      )
    );

    ImageResource imageResource = imageCache.load(testUrl, scale: 1.0);
    expect(find.byKey(new ObjectKey(imageResource)), findsNothing);
  });

  testWidgets('Verify AsyncImage sets an ObjectKey on its ImageResource if it doesn\'t have a key', (WidgetTester tester) {
    ImageProvider imageProvider = new TestImageProvider();
    tester.pumpWidget(new AsyncImage(provider: imageProvider));

    ImageResource imageResource = imageCache.loadProvider(imageProvider);
    expect(find.byKey(new ObjectKey(imageResource)), findsOneWidget);
  });

  testWidgets('Verify AsyncImage doesn\'t set an ObjectKey on its ImageResource if it has a key', (WidgetTester tester) {
    ImageProvider imageProvider = new TestImageProvider();
    tester.pumpWidget(
      new AsyncImage(
        key: new GlobalKey(),
        provider: imageProvider
      )
    );

    ImageResource imageResource = imageCache.loadProvider(imageProvider);
    expect(find.byKey(new ObjectKey(imageResource)), findsNothing);
  });

  testWidgets('Verify AssetImage sets an ObjectKey on its ImageResource if it doesn\'t have a key', (WidgetTester tester) {
    final String name = 'foo';
    final AssetBundle assetBundle = new TestAssetBundle();
    tester.pumpWidget(
      new AssetImage(
        name: name,
        bundle: assetBundle
      )
    );

    ImageResource imageResource = assetBundle.loadImage(name);
    expect(find.byKey(new ObjectKey(imageResource)), findsOneWidget);
  });

  testWidgets('Verify AssetImage doesn\'t set an ObjectKey on its ImageResource if it has a key', (WidgetTester tester) {
    final String name = 'foo';
    final AssetBundle assetBundle = new TestAssetBundle();
    tester.pumpWidget(
      new AssetImage(
        key: new GlobalKey(),
        name: name,
        bundle: assetBundle
      )
    );

    ImageResource imageResource = assetBundle.loadImage(name);
    expect(find.byKey(new ObjectKey(imageResource)), findsNothing);
  });

  testWidgets('Verify AsyncImage resets its RenderImage when changing providers if it doesn\'t have a key', (WidgetTester tester) {
    final GlobalKey key = new GlobalKey();
    TestImageProvider imageProvider1 = new TestImageProvider();
    tester.pumpWidget(
      new Container(
        key: key,
        child: new AsyncImage(
          provider: imageProvider1
        )
      ),
      null,
      EnginePhase.layout
    );
    RenderImage renderImage = key.currentContext.findRenderObject();
    expect(renderImage.image, isNull);

    imageProvider1.complete();
    tester.flushMicrotasks(); // resolve the future from the image provider
    tester.pump(null, EnginePhase.layout);

    renderImage = key.currentContext.findRenderObject();
    expect(renderImage.image, isNotNull);

    TestImageProvider imageProvider2 = new TestImageProvider();
    tester.pumpWidget(
      new Container(
        key: key,
        child: new AsyncImage(
          provider: imageProvider2
        )
      ),
      null,
      EnginePhase.layout
    );

    renderImage = key.currentContext.findRenderObject();
    expect(renderImage.image, isNull);

  });

  testWidgets('Verify AsyncImage doesn\'t reset its RenderImage when changing providers if it has a key', (WidgetTester tester) {
    final GlobalKey key = new GlobalKey();
    TestImageProvider imageProvider1 = new TestImageProvider();
    tester.pumpWidget(
      new AsyncImage(
          key: key,
          provider: imageProvider1
      ),
      null,
      EnginePhase.layout
    );
    RenderImage renderImage = key.currentContext.findRenderObject();
    expect(renderImage.image, isNull);

    imageProvider1.complete();
    tester.flushMicrotasks(); // resolve the future from the image provider
    tester.pump(null, EnginePhase.layout);

    renderImage = key.currentContext.findRenderObject();
    expect(renderImage.image, isNotNull);

    TestImageProvider imageProvider2 = new TestImageProvider();
    tester.pumpWidget(
      new AsyncImage(
        key: key,
        provider: imageProvider2
      ),
      null,
      EnginePhase.layout
    );

    renderImage = key.currentContext.findRenderObject();
    expect(renderImage.image, isNotNull);
  });

}

class TestImageProvider extends ImageProvider {
  final Completer<ImageInfo> _completer = new Completer<ImageInfo>();

  @override
  Future<ImageInfo> loadImage() => _completer.future;

  void complete() {
    _completer.complete(new ImageInfo(image:new TestImage()));
  }
}

class TestAssetBundle extends AssetBundle {
  final ImageResource _imageResource = new ImageResource(new Completer<ImageInfo>().future);

  @override
  ImageResource loadImage(String key) => _imageResource;

  @override
  Future<String> loadString(String key) => new Completer<String>().future;

  @override
  Future<core.MojoDataPipeConsumer> load(String key) => new Completer<core.MojoDataPipeConsumer>().future;
}

class TestImage extends ui.Image {
  @override
  int get width => 100;

  @override
  int get height => 100;

  @override
  void dispose() {
  }
}