ui/file_manager/file_manager/foreground/js/mock_thumbnail_loader.js

// 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.

/**
 * Mock thumbnail loader.
 */
class MockThumbnailLoader {
  /**
   * @param {Entry} entry An entry.
   * @param {ThumbnailLoader.LoaderType=} opt_loaderType Loader type.
   * @param {Object=} opt_metadata Metadata.
   * @param {string=} opt_mediaType Media type.
   * @param {Array<ThumbnailLoader.LoadTarget>=} opt_loadTargets Load targets.
   * @param {number=} opt_priority Priority.
   */
  constructor(
      entry, opt_loaderType, opt_metadata, opt_mediaType, opt_loadTargets,
      opt_priority) {
    this.entry_ = entry;
  }

  /**
   * Loads thumbnail as data url.
   *
   * @return {!Promise<{data:?string, width:number, height:number}>} A
   *     promise which is resolved with data url.
   */
  loadAsDataUrl() {
    if (MockThumbnailLoader.errorUrls.indexOf(this.entry_.toURL()) !== -1) {
      throw new Error('Failed to load thumbnail.');
    }

    return Promise.resolve({
      data: MockThumbnailLoader.testImageDataUrl,
      width: MockThumbnailLoader.testImageWidth,
      height: MockThumbnailLoader.testImageHeight
    });
  }
}

/**
 * Data url of test image.
 * @private {?string}
 */
MockThumbnailLoader.testImageDataUrl = null;

/**
 * Width of test image.
 * @private {number}
 */
MockThumbnailLoader.testImageWidth = 0;

/**
 * Height of test image.
 * @private {number}
 */
MockThumbnailLoader.testImageHeight = 0;

/**
 * Error urls.
 * @private {Array<string>}
 */
MockThumbnailLoader.errorUrls = [];