Added Internet Explorer compatibility for JSON and toString.call

Author: sskates

src/amplitude.js

@@ -15,7 +15,7 @@
      * Checks if an object is an array
      */
     var isArray = Array.isArray || function(obj) {
-        return toString.call(obj) === '[object Array]';
+        return Object.prototype.toString.call(obj) === '[object Array]';
     };
 
     /*
@@ -271,6 +271,338 @@
         }
     };
 
+    /*
+     * JSON stringify/parse
+     * https://github.com/douglascrockford/JSON-js
+     * json2.js
+     */
+    var JSON = window.JSON;
+    if (typeof JSON !== 'object') {
+        JSON = {};
+    }
+
+    (function () {
+        'use strict';
+
+        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) {
+                        if (typeof rep[i] === 'string') {
+                            k = rep[i];
+                            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.prototype.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 JSON.stringify !== 'function') {
+            JSON.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 JSON.parse !== 'function') {
+            JSON.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.prototype.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');
+            };
+        }
+    }());
+
     var userAgent = navigator.userAgent;
     var vendor = navigator.vendor;
     var platform = navigator.platform;