Add wallpaper api tests

chrome/test/data/extensions/api_test/wallpaper/test.js

+// Copyright 2014 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.
+
+var pass = chrome.test.callbackPass;
+var fail = chrome.test.callbackFail;
+
+chrome.test.getConfig(function(config) {
+
+  var baseURL = "http://a.com:" + config.testServer.port +
+      "/extensions/api_test/wallpaper/";
+
+  /*
+   * Calls chrome.wallpaper.setWallpaper using an arraybuffer.
+   * @param {string} filePath An extension relative file path.
+   */
+  var testSetWallpaperFromArrayBuffer = function (filePath) {
+    // Loads an extension local file to an arraybuffer.
+    var url = chrome.runtime.getURL(filePath);
+    var wallpaperRequest = new XMLHttpRequest();
+    wallpaperRequest.open('GET', url, true);
+    wallpaperRequest.responseType = 'arraybuffer';
+    try {
+      wallpaperRequest.send(null);
+      wallpaperRequest.onloadend = function(e) {
+        if (wallpaperRequest.status === 200) {
+          chrome.wallpaper.setWallpaper(
+              {'wallpaperData': wallpaperRequest.response,
+               'layout': 'CENTER_CROPPED',
+               'name': 'test'},
+              // Set wallpaper directly with an arraybuffer should pass.
+              pass()
+          );
+        } else {
+          chrome.test.fail('Failed to load local file: ' + filePath + '.');
+        }
+      };
+    } catch (e) {
+      console.error(e);
+      chrome.test.fail('An error thrown when requesting wallpaper.');
+    }
+  };
+
+  /*
+   * Calls chrome.wallpaper.setWallpaper using an URL.
+   * @param {string} relativeURL The relative URL of an online image.
+   * @param {boolean} success True if expecting the API call success.
+   * @param {string=} optExpectedError The expected error string if API call
+   *     failed. An error string must be provided if success is set to false.
+   */
+  var testSetWallpaperFromURL = function (relativeURL,
+                                          success,
+                                          optExpectedError) {
+    var url = baseURL + relativeURL;
+    if (success) {
+      chrome.wallpaper.setWallpaper(
+          {'url': url,
+           'layout': 'CENTER_CROPPED',
+           'name': 'test'},
+           // A valid url should set wallpaper correctly.
+           pass()
+      );
+    } else {
+      if (optExpectedError == undefined) {
+        chrome.test.fail('No expected error string is provided.');
+        return;
+      }
+      chrome.wallpaper.setWallpaper(
+         {'url': url,
+          'layout': 'CENTER_CROPPED',
+          'name': 'test'},
+          // Expect a failure.
+          fail(optExpectedError));
+    }
+  };
+
+  chrome.test.runTests([
+    function setJpgWallpaperFromAppLocalFile() {
+      testSetWallpaperFromArrayBuffer('test.jpg');
+    },
+    function setPngWallpaperFromAppLocalFile() {
+      testSetWallpaperFromArrayBuffer('test.png');
+    },
+    function setJpgWallpaperFromURL () {
+      testSetWallpaperFromURL('test.jpg', true);
+    },
+    function setPngWallpaperFromURL () {
+      testSetWallpaperFromURL('test.png', true);
+    },
+    function setNoExistingWallpaperFromURL () {
+      // test1.jpg doesn't exist. Expect Chrome cannot set wallpaper failure.
+      testSetWallpaperFromURL('test1.jpg',
+                              false,
+                              'Chrome cannot set wallpaper.');
+    },
+    function newRequestCancelPreviousRequest() {
+      // The first request should be canceled.
+      testSetWallpaperFromURL('test.png',
+                              false,
+                              'Downloading wallpaper test.png is canceled.');
+      testSetWallpaperFromURL('test.jpg', true);
+    }
+  ]);
+});