chrome/test/chromedriver/js/execute_async_script.js

   1 // Copyright (c) 2013 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 /**
   6  * Enum for WebDriver status codes.
   7  * @enum {number}
   8  */
   9 var StatusCode = {
  10   OK: 0,
  11   UNKNOWN_ERROR: 13,
  12   JAVASCRIPT_ERROR: 17,
  13   SCRIPT_TIMEOUT: 28,
  14 };
  15
  16 /**
  17  * Dictionary key for asynchronous script info.
  18  * @const
  19  */
  20 var ASYNC_INFO_KEY = '$chrome_asyncScriptInfo';
  21
  22 /**
  23 * Return the information of asynchronous script execution.
  24 *
  25 * @return {Object<string, ?>} Information of asynchronous script execution.
  26 */
  27 function getAsyncScriptInfo() {
  28   if (!(ASYNC_INFO_KEY in document))
  29     document[ASYNC_INFO_KEY] = {'id': 0};
  30   return document[ASYNC_INFO_KEY];
  31 }
  32
  33 /**
  34 * Execute the given script and save its asynchronous result.
  35 *
  36 * If script1 finishes after script2 is executed, then script1's result will be
  37 * discarded while script2's will be saved.
  38 *
  39 * @param {string} script The asynchronous script to be executed. The script
  40 *     should be a proper function body. It will be wrapped in a function and
  41 *     invoked with the given arguments and, as the final argument, a callback
  42 *     function to invoke to report the asynchronous result.
  43 * @param {!Array<*>} args Arguments to be passed to the script.
  44 * @param {boolean} isUserSupplied Whether the script is supplied by the user.
  45 *     If not, UnknownError will be used instead of JavaScriptError if an
  46 *     exception occurs during the script, and an additional error callback will
  47 *     be supplied to the script.
  48 * @param {?number} opt_timeoutMillis The timeout, in milliseconds, to use.
  49 *     If the timeout is exceeded and the callback has not been invoked, a error
  50 *     result will be saved and future invocation of the callback will be
  51 *     ignored.
  52 */
  53 function executeAsyncScript(script, args, isUserSupplied, opt_timeoutMillis) {
  54   var info = getAsyncScriptInfo();
  55   info.id++;
  56   delete info.result;
  57   var id = info.id;
  58
  59   function report(status, value) {
  60     if (id != info.id)
  61       return;
  62     info.id++;
  63     info.result = {status: status, value: value};
  64   }
  65   function reportValue(value) {
  66     report(StatusCode.OK, value);
  67   }
  68   function reportScriptError(error) {
  69     var code = isUserSupplied ? StatusCode.JAVASCRIPT_ERROR :
  70                                 (error.code || StatusCode.UNKNOWN_ERROR);
  71     var message = error.message;
  72     if (error.stack) {
  73       message += "\nJavaScript stack:\n" + error.stack;
  74     }
  75     report(code, message);
  76   }
  77   args.push(reportValue);
  78   if (!isUserSupplied)
  79     args.push(reportScriptError);
  80
  81   try {
  82     new Function(script).apply(null, args);
  83   } catch (error) {
  84     reportScriptError(error);
  85     return;
  86   }
  87
  88   if (typeof(opt_timeoutMillis) != 'undefined') {
  89     window.setTimeout(function() {
  90       var code = isUserSupplied ? StatusCode.SCRIPT_TIMEOUT :
  91                                   StatusCode.UNKNOWN_ERROR;
  92       var errorMsg = 'result was not received in ' + opt_timeoutMillis / 1000 +
  93                      ' seconds';
  94       report(code, errorMsg);
  95     }, opt_timeoutMillis);
  96   }
  97 }