packages/flutter/test/painting/binding_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 'dart:typed_data' show Uint8List;

import 'package:flutter_test/flutter_test.dart';
import 'package:flutter/widgets.dart';
import 'package:flutter/painting.dart';

import 'image_data.dart';
import 'painting_utils.dart';

void main() {
  final PaintingBindingSpy binding = PaintingBindingSpy();

  test('instantiateImageCodec used for loading images', () async {
    expect(binding.instantiateImageCodecCalledCount, 0);

    final Uint8List bytes = Uint8List.fromList(kTransparentImage);
    final MemoryImage memoryImage = MemoryImage(bytes);
    memoryImage.load(memoryImage, (Uint8List bytes, {int cacheWidth, int cacheHeight}) {
      return PaintingBinding.instance.instantiateImageCodec(bytes, cacheWidth: cacheWidth, cacheHeight: cacheHeight);
    });
    expect(binding.instantiateImageCodecCalledCount, 1);
  });
}