Index: chrome/browser/resources/access_chromevox/common/chromevox_json.js |
=================================================================== |
--- chrome/browser/resources/access_chromevox/common/chromevox_json.js (revision 0) |
+++ chrome/browser/resources/access_chromevox/common/chromevox_json.js (revision 0) |
@@ -0,0 +1,357 @@ |
+// Copyright (c) 2011 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. |
+ |
+goog.provide('cvox.ChromeVoxJSON'); |
+ |
+/** |
+ * @fileoverview A simple wrapper around the JSON APIs. |
+ * If it is possible to use the browser's built in native JSON, then |
+ * cvox.ChromeVoxJSON is the same as JSON. |
+ * If the page has its own version of JSON, cvox.ChromeVoxJSON will use its |
+ * own implementation (rather than the version of JSON on the page |
+ * which may be outdated/broken). |
+ */ |
+ |
+if (!cvox.ChromeVoxJSON) { |
+ /** |
+ * @type {Object} |
+ */ |
+ cvox.ChromeVoxJSON = {}; |
+} |
+ |
+if (JSON.toString() == '[object JSON]') { |
+ cvox.ChromeVoxJSON = JSON; |
+} else { |
+ /* |
+ * JSON implementation renamed to cvox.ChromeVoxJSON. |
+ * This only gets called if the page has its own version of JSON. |
+ * |
+ * Based on: |
+ * http://www.JSON.org/json2.js |
+ * 2010-03-20 |
+ * |
+ * Public Domain. |
+ * |
+ * NO WARRANTY EXPRESSED OR IMPLIED. USE AT YOUR OWN RISK. |
+ * |
+ * See http://www.JSON.org/js.html |
+ */ |
+ (function() { |
+ function f(n) { |
+ // Format integers to have at least two digits. |
+ return n < 10 ? '0' + n : n; |
+ } |
+ |
+ if (typeof Date.prototype.toJSON !== 'function') { |
+ |
+ Date.prototype.toJSON = function(key) { |
+ |
+ return isFinite(this.valueOf()) ? |
+ this.getUTCFullYear() + '-' + |
+ f(this.getUTCMonth() + 1) + '-' + |
+ f(this.getUTCDate()) + 'T' + |
+ f(this.getUTCHours()) + ':' + |
+ f(this.getUTCMinutes()) + ':' + |
+ f(this.getUTCSeconds()) + 'Z' : 'null'; |
+ }; |
+ |
+ String.prototype.toJSON = |
+ Number.prototype.toJSON = |
+ Boolean.prototype.toJSON = function(key) { |
+ return this.valueOf(); |
+ }; |
+ } |
+ |
+ var cx = /[\u0000\u00ad\u0600-\u0604\u070f\u17b4\u17b5\u200c-\u200f\u2028-\u202f\u2060-\u206f\ufeff\ufff0-\uffff]/g, |
+ escapable = /[\\\"\x00-\x1f\x7f-\x9f\u00ad\u0600-\u0604\u070f\u17b4\u17b5\u200c-\u200f\u2028-\u202f\u2060-\u206f\ufeff\ufff0-\uffff]/g, |
+ gap, |
+ indent, |
+ meta = { // table of character substitutions |
+ '\b': '\\b', |
+ '\t': '\\t', |
+ '\n': '\\n', |
+ '\f': '\\f', |
+ '\r': '\\r', |
+ '"' : '\\"', |
+ '\\': '\\\\' |
+ }, |
+ rep; |
+ |
+ |
+ function quote(string) { |
+ |
+ // If the string contains no control characters, no quote characters, and |
+ // no backslash characters, then we can safely slap some quotes around it. |
+ // Otherwise we must also replace the offending characters with safe |
+ // escape sequences. |
+ |
+ escapable.lastIndex = 0; |
+ return escapable.test(string) ? |
+ '"' + string.replace(escapable, function(a) { |
+ var c = meta[a]; |
+ return typeof c === 'string' ? c : |
+ '\\u' + ('0000' + a.charCodeAt(0).toString(16)).slice(-4); |
+ }) + '"' : |
+ '"' + string + '"'; |
+ } |
+ |
+ |
+ function str(key, holder) { |
+ |
+ // Produce a string from holder[key]. |
+ |
+ var i, // The loop counter. |
+ k, // The member key. |
+ v, // The member value. |
+ length, |
+ mind = gap, |
+ partial, |
+ value = holder[key]; |
+ |
+ // If the value has a toJSON method, call it to obtain a replacement |
+ // value. |
+ |
+ if (value && typeof value === 'object' && |
+ typeof value.toJSON === 'function') { |
+ value = value.toJSON(key); |
+ } |
+ |
+ // If we were called with a replacer function, then call the replacer to |
+ // obtain a replacement value. |
+ |
+ if (typeof rep === 'function') { |
+ value = rep.call(holder, key, value); |
+ } |
+ |
+ // What happens next depends on the value's type. |
+ |
+ switch (typeof value) { |
+ case 'string': |
+ return quote(value); |
+ |
+ case 'number': |
+ // JSON numbers must be finite. Encode non-finite numbers as null. |
+ return isFinite(value) ? String(value) : 'null'; |
+ |
+ case 'boolean': |
+ case 'null': |
+ // If the value is a boolean or null, convert it to a string. Note: |
+ // typeof null does not produce 'null'. The case is included here in |
+ // the remote chance that this gets fixed someday. |
+ return String(value); |
+ |
+ // If the type is 'object', we might be dealing with an object or an |
+ // array or null. |
+ |
+ case 'object': |
+ |
+ // Due to a specification blunder in ECMAScript, typeof null is |
+ // 'object', so watch out for that case. |
+ |
+ if (!value) { |
+ return 'null'; |
+ } |
+ |
+ // Make an array to hold the partial results of stringifying this |
+ // object value. |
+ |
+ gap += indent; |
+ partial = []; |
+ |
+ // Is the value an array? |
+ |
+ if (Object.prototype.toString.apply(value) === '[object Array]') { |
+ |
+ // The value is an array. Stringify every element. Use null as a |
+ // placeholder for non-JSON values. |
+ |
+ length = value.length; |
+ for (i = 0; i < length; i += 1) { |
+ partial[i] = str(i, value) || 'null'; |
+ } |
+ |
+ // Join all of the elements together, separated with commas, and |
+ // wrap them in brackets. |
+ |
+ v = partial.length === 0 ? '[]' : |
+ gap ? '[\n' + gap + |
+ partial.join(',\n' + gap) + '\n' + |
+ mind + ']' : |
+ '[' + partial.join(',') + ']'; |
+ gap = mind; |
+ return v; |
+ } |
+ |
+ // If the replacer is an array, use it to select the members to be |
+ // stringified. |
+ |
+ if (rep && typeof rep === 'object') { |
+ length = rep.length; |
+ for (i = 0; i < length; i += 1) { |
+ k = rep[i]; |
+ if (typeof k === 'string') { |
+ v = str(k, value); |
+ if (v) { |
+ partial.push(quote(k) + (gap ? ': ' : ':') + v); |
+ } |
+ } |
+ } |
+ } else { |
+ |
+ // Otherwise, iterate through all of the keys in the object. |
+ for (k in value) { |
+ if (Object.hasOwnProperty.call(value, k)) { |
+ v = str(k, value); |
+ if (v) { |
+ partial.push(quote(k) + (gap ? ': ' : ':') + v); |
+ } |
+ } |
+ } |
+ } |
+ |
+ // Join all of the member texts together, separated with commas, |
+ // and wrap them in braces. |
+ |
+ v = partial.length === 0 ? '{}' : |
+ gap ? '{\n' + gap + partial.join(',\n' + gap) + '\n' + |
+ mind + '}' : '{' + partial.join(',') + '}'; |
+ gap = mind; |
+ return v; |
+ } |
+ } |
+ |
+ // If the JSON object does not yet have a stringify method, give it one. |
+ |
+ if (typeof cvox.ChromeVoxJSON.stringify !== 'function') { |
+ cvox.ChromeVoxJSON.stringify = function(value, replacer, space) { |
+ |
+ // The stringify method takes a value and an optional replacer, and an |
+ // optional space parameter, and returns a JSON text. The replacer can |
+ // be a function that can replace values, or an array of strings that |
+ // will select the keys. A default replacer method can be provided. Use |
+ // of the space parameter can produce text that is more easily readable. |
+ |
+ var i; |
+ gap = ''; |
+ indent = ''; |
+ |
+ // If the space parameter is a number, make an indent string containing |
+ // that many spaces. |
+ |
+ if (typeof space === 'number') { |
+ for (i = 0; i < space; i += 1) { |
+ indent += ' '; |
+ } |
+ |
+ // If the space parameter is a string, it will be used as the indent |
+ // string. |
+ |
+ } else if (typeof space === 'string') { |
+ indent = space; |
+ } |
+ |
+ // If there is a replacer, it must be a function or an array. |
+ // Otherwise, throw an error. |
+ |
+ rep = replacer; |
+ if (replacer && typeof replacer !== 'function' && |
+ (typeof replacer !== 'object' || |
+ typeof replacer.length !== 'number')) { |
+ throw new Error('JSON.stringify'); |
+ } |
+ |
+ // Make a fake root object containing our value under the key of ''. |
+ // Return the result of stringifying the value. |
+ |
+ return str('', {'': value}); |
+ }; |
+ } |
+ |
+ |
+ // If the JSON object does not yet have a parse method, give it one. |
+ |
+ if (typeof cvox.ChromeVoxJSON.parse !== 'function') { |
+ cvox.ChromeVoxJSON.parse = function(text, reviver) { |
+ |
+ // The parse method takes a text and an optional reviver function, and |
+ // returns a JavaScript value if the text is a valid JSON text. |
+ |
+ var j; |
+ |
+ function walk(holder, key) { |
+ |
+ // The walk method is used to recursively walk the resulting structure |
+ // so that modifications can be made. |
+ |
+ var k, v, value = holder[key]; |
+ if (value && typeof value === 'object') { |
+ for (k in value) { |
+ if (Object.hasOwnProperty.call(value, k)) { |
+ v = walk(value, k); |
+ if (v !== undefined) { |
+ value[k] = v; |
+ } else { |
+ delete value[k]; |
+ } |
+ } |
+ } |
+ } |
+ return reviver.call(holder, key, value); |
+ } |
+ |
+ |
+ // Parsing happens in four stages. In the first stage, we replace |
+ // certain Unicode characters with escape sequences. JavaScript handles |
+ // many characters incorrectly, either silently deleting them, or |
+ // treating them as line endings. |
+ |
+ text = String(text); |
+ cx.lastIndex = 0; |
+ if (cx.test(text)) { |
+ text = text.replace(cx, function(a) { |
+ return '\\u' + |
+ ('0000' + a.charCodeAt(0).toString(16)).slice(-4); |
+ }); |
+ } |
+ |
+ // In the second stage, we run the text against regular expressions that |
+ // look for non-JSON patterns. We are especially concerned with '()' and |
+ // 'new' because they can cause invocation, and '=' because it can cause |
+ // mutation. But just to be safe, we want to reject all unexpected |
+ // forms. |
+ // We split the second stage into 4 regexp operations in order to work |
+ // around crippling inefficiencies in IE's and Safari's regexp engines. |
+ // First we replace the JSON backslash pairs with '@' (a non-JSON |
+ // character). Second, we replace all simple value tokens with ']' |
+ // characters. Third, we delete all open brackets that follow a colon or |
+ // comma or that begin the text. Finally, we look to see that the |
+ // remaining characters are only whitespace or ']' or ',' or ':' or '{' |
+ // or '}'. If that is so, then the text is safe for eval. |
+ |
+ if (/^[\],:{}\s]*$/. |
+ test(text.replace(/\\(?:["\\\/bfnrt]|u[0-9a-fA-F]{4})/g, '@'). |
+ replace(/"[^"\\\n\r]*"|true|false|null|-?\d+(?:\.\d*)?(?:[eE][+\-]?\d+)?/g, ']'). |
+ replace(/(?:^|:|,)(?:\s*\[)+/g, ''))) { |
+ |
+ // In the third stage we use the eval function to compile the text |
+ // into a JavaScript structure. The '{' operator is subject to a |
+ // syntactic ambiguity in JavaScript: it can begin a block or an |
+ // object literal. We wrap the text in parens to eliminate the |
+ // ambiguity. |
+ |
+ j = eval('(' + text + ')'); |
+ |
+ // In the optional fourth stage, we recursively walk the new |
+ // structure, passing each name/value pair to a reviver function for |
+ // possible transformation. |
+ return typeof reviver === 'function' ? walk({'': j}, '') : j; |
+ } |
+ |
+ // If the text is not JSON parseable, then a SyntaxError is thrown. |
+ |
+ throw new SyntaxError('JSON.parse'); |
+ }; |
+ } |
+ }()); |
+} |
Property changes on: chrome/browser/resources/access_chromevox/common/chromevox_json.js |
___________________________________________________________________ |
Added: svn:executable |
+ * |
Added: svn:eol-style |
+ LF |