Home | History | Annotate | Download | only in closure 
      1 // Copyright 2014 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  * @fileoverview Code to execute before Closure's base.js.
      7  *
      8  */
      9 
     10 /**
     11  * Tell Closure to load JavaScript code from the extension root directory.
     12  * @type {boolean}
     13  */
     14 window.CLOSURE_BASE_PATH = chrome.extension.getURL('/closure/');
     15 
     16 /**
     17  * Tell Closure not to load deps.js; it's included by manifest.json already.
     18  * @type {boolean}
     19  */
     20 window.CLOSURE_NO_DEPS = true;
     21 
     22 /**
     23  * Array of urls that should be included next, in order.
     24  * @type {Array}
     25  * @private
     26  */
     27 window.queue_ = [];
     28 
     29 /**
     30  * Custom function for importing ChromeVox scripts.
     31  * @param {string} src The JS file to import.
     32  * @return {boolean} Whether the script was imported.
     33  */
     34 window.CLOSURE_IMPORT_SCRIPT = function(src) {
     35   // Only run our version of the import script
     36   // when trying to inject ChromeVox scripts.
     37   if (src.indexOf('chrome-extension://') == 0) {
     38     if (!goog.inHtmlDocument_() ||
     39         goog.dependencies_.written[src]) {
     40       return false;
     41     }
     42     goog.dependencies_.written[src] = true;
     43     function loadNextScript() {
     44       if (goog.global.queue_.length == 0)
     45         return;
     46 
     47       var src = goog.global.queue_[0];
     48 
     49       if (window.CLOSURE_USE_EXT_MESSAGES) {
     50         var relativeSrc = src.substr(src.indexOf('closure/..') + 11);
     51         chrome.extension.sendMessage(
     52             {'srcFile': relativeSrc},
     53             function(response) {
     54               try {
     55                 eval(response['code']);
     56               } catch (e) {
     57                 console.error('Script error: ' + e + ' in ' + src);
     58               }
     59               goog.global.queue_ = goog.global.queue_.slice(1);
     60               loadNextScript();
     61             });
     62         return;
     63       }
     64       window.console.log('Using XHR');
     65 
     66       // Load the script by fetching its source and running 'eval' on it
     67       // directly, with a magic comment that makes Chrome treat it like it
     68       // loaded normally. Wait until it's fetched before loading the
     69       // next script.
     70       var xhr = new XMLHttpRequest();
     71       var url = src + '?' + new Date().getTime();
     72       xhr.onreadystatechange = function() {
     73         if (xhr.readyState == 4) {
     74           var scriptText = xhr.responseText;
     75           // Add a magic comment to the bottom of the file so that
     76           // Chrome knows the name of the script in the JavaScript debugger.
     77           scriptText += '\n//# sourceURL=' + src + '\n';
     78           eval(scriptText);
     79           goog.global.queue_ = goog.global.queue_.slice(1);
     80           loadNextScript();
     81         }
     82       };
     83       xhr.open('GET', url, false);
     84       xhr.send(null);
     85     }
     86     goog.global.queue_.push(src);
     87     if (goog.global.queue_.length == 1) {
     88       loadNextScript();
     89     }
     90     return true;
     91   } else {
     92     return goog.writeScriptTag_(src);
     93   }
     94 };
     95