Make Utils.js use Object.define to modify Array

Previously, we were modifying Array's prototype using
simple assignment.  This can mess with enumeration/iteration.
Thus, we now use Object.defineProperty with enumerable set to
false.

See #366
This commit is contained in:
Solly Ross 2014-09-22 22:30:19 -04:00
parent 58529d347b
commit f9fd0313b8
1 changed files with 62 additions and 61 deletions

View File

@ -17,30 +17,36 @@ var Util = {};
* Make arrays quack * Make arrays quack
*/ */
Array.prototype.push8 = function (num) { var addFunc = function (cl, name, func) {
"use strict"; if (!cl.prototype[name]) {
this.push(num & 0xFF); Object.defineProperty(cl.prototype, name, { enumerable: false, value: func });
}
}; };
Array.prototype.push16 = function (num) { addFunc(Array, 'push8', function (num) {
"use strict";
this.push(num & 0xFF);
});
addFunc(Array, 'push16', function (num) {
"use strict"; "use strict";
this.push((num >> 8) & 0xFF, this.push((num >> 8) & 0xFF,
num & 0xFF); num & 0xFF);
}; });
Array.prototype.push32 = function (num) {
addFunc(Array, 'push32', function (num) {
"use strict"; "use strict";
this.push((num >> 24) & 0xFF, this.push((num >> 24) & 0xFF,
(num >> 16) & 0xFF, (num >> 16) & 0xFF,
(num >> 8) & 0xFF, (num >> 8) & 0xFF,
num & 0xFF); num & 0xFF);
}; });
// IE does not support map (even in IE9) // IE does not support map (even in IE9)
//This prototype is provided by the Mozilla foundation and //This prototype is provided by the Mozilla foundation and
//is distributed under the MIT license. //is distributed under the MIT license.
//http://www.ibiblio.org/pub/Linux/LICENSES/mit.license //http://www.ibiblio.org/pub/Linux/LICENSES/mit.license
if (!Array.prototype.map) { addFunc(Array, 'map', function (fun /*, thisp*/) {
Array.prototype.map = function (fun /*, thisp*/) {
"use strict"; "use strict";
var len = this.length; var len = this.length;
if (typeof fun != "function") { if (typeof fun != "function") {
@ -56,15 +62,13 @@ if (!Array.prototype.map) {
} }
return res; return res;
}; });
}
// IE <9 does not support indexOf // IE <9 does not support indexOf
//This prototype is provided by the Mozilla foundation and //This prototype is provided by the Mozilla foundation and
//is distributed under the MIT license. //is distributed under the MIT license.
//http://www.ibiblio.org/pub/Linux/LICENSES/mit.license //http://www.ibiblio.org/pub/Linux/LICENSES/mit.license
if (!Array.prototype.indexOf) { addFunc(Array, 'indexOf', function (elt /*, from*/) {
Array.prototype.indexOf = function (elt /*, from*/) {
"use strict"; "use strict";
var len = this.length >>> 0; var len = this.length >>> 0;
@ -81,8 +85,7 @@ if (!Array.prototype.indexOf) {
} }
} }
return -1; return -1;
}; });
}
// From https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/keys // From https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/keys
if (!Object.keys) { if (!Object.keys) {
@ -131,8 +134,7 @@ if (!Object.keys) {
//This prototype is provided by the Mozilla foundation and //This prototype is provided by the Mozilla foundation and
//is distributed under the MIT license. //is distributed under the MIT license.
//http://www.ibiblio.org/pub/Linux/LICENSES/mit.license //http://www.ibiblio.org/pub/Linux/LICENSES/mit.license
if (!Function.prototype.bind) { addFunc(Function, 'bind', function (oThis) {
Function.prototype.bind = function (oThis) {
if (typeof this !== "function") { if (typeof this !== "function") {
// closest thing possible to the ECMAScript 5 // closest thing possible to the ECMAScript 5
// internal IsCallable function // internal IsCallable function
@ -153,8 +155,7 @@ if (!Function.prototype.bind) {
fBound.prototype = new fNOP(); fBound.prototype = new fNOP();
return fBound; return fBound;
}; });
}
// //
// requestAnimationFrame shim with setTimeout fallback // requestAnimationFrame shim with setTimeout fallback