testing/dart/image_descriptor_test.dart

// Copyright 2013 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:async';
import 'dart:io';
import 'dart:typed_data';
import 'dart:ui';

import 'package:litetest/litetest.dart';
import 'package:path/path.dart' as path;

void main() {
  test('basic image descriptor - encoded - greyscale', () async {
    final Uint8List bytes = await readFile('2x2.png');
    final ImmutableBuffer buffer = await ImmutableBuffer.fromUint8List(bytes);
    final ImageDescriptor descriptor = await ImageDescriptor.encoded(buffer);

    expect(descriptor.width, 2);
    expect(descriptor.height, 2);
    expect(descriptor.bytesPerPixel, 1);

    final Codec codec = await descriptor.instantiateCodec();
    expect(codec.frameCount, 1);
  });

  test('basic image descriptor - encoded - square', () async {
    final Uint8List bytes = await readFile('square.png');
    final ImmutableBuffer buffer = await ImmutableBuffer.fromUint8List(bytes);
    final ImageDescriptor descriptor = await ImageDescriptor.encoded(buffer);

    expect(descriptor.width, 10);
    expect(descriptor.height, 10);
    expect(descriptor.bytesPerPixel, 4);

    final Codec codec = await descriptor.instantiateCodec();
    expect(codec.frameCount, 1);
  });

  test('basic image descriptor - encoded - animated', () async {
    final Uint8List bytes = await _getSkiaResource('test640x479.gif').readAsBytes();
    final ImmutableBuffer buffer = await ImmutableBuffer.fromUint8List(bytes);
    final ImageDescriptor descriptor = await ImageDescriptor.encoded(buffer);

    expect(descriptor.width, 640);
    expect(descriptor.height, 479);
    expect(descriptor.bytesPerPixel, 4);

    final Codec codec = await descriptor.instantiateCodec();
    expect(codec.frameCount, 4);
    expect(codec.repetitionCount, -1);
  });

  test('basic image descriptor - raw', () async {
    final Uint8List bytes = Uint8List.fromList(List<int>.filled(16, 0xFFABCDEF));
    final ImmutableBuffer buffer = await ImmutableBuffer.fromUint8List(bytes);
    final ImageDescriptor descriptor = ImageDescriptor.raw(
      buffer,
      width: 4,
      height: 4,
      rowBytes: 4 * 4,
      pixelFormat: PixelFormat.rgba8888,
    );

    expect(descriptor.width, 4);
    expect(descriptor.height, 4);
    expect(descriptor.bytesPerPixel, 4);

    final Codec codec = await descriptor.instantiateCodec();
    expect(codec.frameCount, 1);
  });

  test('HEIC image', () async {
    final Uint8List bytes = await readFile('grill_chicken.heic');
    final ImmutableBuffer buffer = await ImmutableBuffer.fromUint8List(bytes);
    final ImageDescriptor descriptor = await ImageDescriptor.encoded(buffer);

    expect(descriptor.width, 300);
    expect(descriptor.height, 400);
    expect(descriptor.bytesPerPixel, 4);

    final Codec codec = await descriptor.instantiateCodec();
    expect(codec.frameCount, 1);
  }, skip: !(Platform.isAndroid || Platform.isIOS || Platform.isMacOS || Platform.isWindows));
}

Future<Uint8List> readFile(String fileName, ) async {
  final File file =
      File(path.join('flutter', 'testing', 'resources', fileName));
  return file.readAsBytes();
}

/// Returns a File handle to a file in the skia/resources directory.
File _getSkiaResource(String fileName) {
  // As Platform.script is not working for flutter_tester
  // (https://github.com/flutter/flutter/issues/12847), this is currently
  // assuming the curent working directory is engine/src.
  // This is fragile and should be changed once the Platform.script issue is
  // resolved.
  final String assetPath = path.join(
    'flutter', 'third_party', 'skia', 'resources', 'images', fileName,
  );
  return File(assetPath);
}