packages/flutter/test/painting/shader_warm_up_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:ui' as ui;

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

class TestCanvas implements Canvas {
  TestCanvas();

  final List<Invocation> invocations = <Invocation>[];

  @override
  void noSuchMethod(Invocation invocation) {
    invocations.add(invocation);
  }
}

void main() {
  test('DefaultShaderWarmUp has expected canvas invocations', () {
    final TestCanvas canvas = TestCanvas();
    const DefaultShaderWarmUp s = DefaultShaderWarmUp();
    s.warmUpOnCanvas(canvas);

    bool hasDrawRectAfterClipRRect = false;
    for (int i = 0; i < canvas.invocations.length - 1; i += 1) {
      if (canvas.invocations[i].memberName == #clipRRect && canvas.invocations[i + 1].memberName == #drawRect) {
        hasDrawRectAfterClipRRect = true;
        break;
      }
    }

    expect(hasDrawRectAfterClipRRect, true);
  });

  test('ShaderWarmUp.execute disposes the image and picture', () async {
    const DefaultShaderWarmUp shaderWarmUp = DefaultShaderWarmUp();
    late ui.Picture capturedPicture;
    late ui.Image capturedImage;
    debugCaptureShaderWarmUpPicture = (ui.Picture picture) {
      capturedPicture = picture;
      expect(picture.approximateBytesUsed, greaterThan(0));
      return true;
    };
    debugCaptureShaderWarmUpImage = (ui.Image image) {
      capturedImage = image;
      expect(image.width, 100);
      expect(image.height, 100);
      return true;
    };
    await shaderWarmUp.execute();
    expect(
      () => capturedPicture.approximateBytesUsed,
      throwsA(isA<String>().having((String message) => message, 'message', 'Object has been disposed.')),
    );
    expect(capturedImage.debugDisposed, true);
  }, skip: kIsWeb); // Browser doesn't support approximateBytesUsed and doesn't rasterize the picture at this time.
}