js-crc32/ctest/shim.js

238 lines
6.7 KiB
JavaScript
Raw Permalink Normal View History

// From https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/keys
if (!Object.keys) {
Object.keys = (function () {
var hasOwnProperty = Object.prototype.hasOwnProperty,
hasDontEnumBug = !({toString: null}).propertyIsEnumerable('toString'),
dontEnums = [
'toString',
'toLocaleString',
'valueOf',
'hasOwnProperty',
'isPrototypeOf',
'propertyIsEnumerable',
'constructor'
],
dontEnumsLength = dontEnums.length;
return function (obj) {
if (typeof obj !== 'object' && typeof obj !== 'function' || obj === null) throw new TypeError('Object.keys called on non-object');
var result = [];
for (var prop in obj) {
if (hasOwnProperty.call(obj, prop)) result.push(prop);
}
if (hasDontEnumBug) {
for (var i=0; i < dontEnumsLength; i++) {
if (hasOwnProperty.call(obj, dontEnums[i])) result.push(dontEnums[i]);
}
}
return result;
};
})();
}
// From https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/filter
if (!Array.prototype.filter)
{
Array.prototype.filter = function(fun /*, thisp */)
{
"use strict";
if (this == null)
throw new TypeError();
var t = Object(this);
var len = t.length >>> 0;
if (typeof fun != "function")
throw new TypeError();
var res = [];
var thisp = arguments[1];
for (var i = 0; i < len; i++)
{
if (i in t)
{
var val = t[i]; // in case fun mutates this
if (fun.call(thisp, val, i, t))
res.push(val);
}
}
return res;
};
}
// From https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String/Trim
if (!String.prototype.trim) {
String.prototype.trim = function () {
return this.replace(/^\s+|\s+$/g, '');
};
}
// From https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/forEach
if (!Array.prototype.forEach)
{
Array.prototype.forEach = function(fun /*, thisArg */)
{
"use strict";
if (this === void 0 || this === null)
throw new TypeError();
var t = Object(this);
var len = t.length >>> 0;
if (typeof fun !== "function")
throw new TypeError();
var thisArg = arguments.length >= 2 ? arguments[1] : void 0;
for (var i = 0; i < len; i++)
{
if (i in t)
fun.call(thisArg, t[i], i, t);
}
};
}
// Production steps of ECMA-262, Edition 5, 15.4.4.19
// Reference: http://es5.github.com/#x15.4.4.19
if (!Array.prototype.map) {
Array.prototype.map = function(callback, thisArg) {
var T, A, k;
if (this == null) {
throw new TypeError(" this is null or not defined");
}
// 1. Let O be the result of calling ToObject passing the |this| value as the argument.
var O = Object(this);
// 2. Let lenValue be the result of calling the Get internal method of O with the argument "length".
// 3. Let len be ToUint32(lenValue).
var len = O.length >>> 0;
// 4. If IsCallable(callback) is false, throw a TypeError exception.
// See: http://es5.github.com/#x9.11
if (typeof callback !== "function") {
throw new TypeError(callback + " is not a function");
}
// 5. If thisArg was supplied, let T be thisArg; else let T be undefined.
if (thisArg) {
T = thisArg;
}
// 6. Let A be a new array created as if by the expression new Array(len) where Array is
// the standard built-in constructor with that name and len is the value of len.
A = new Array(len);
// 7. Let k be 0
k = 0;
// 8. Repeat, while k < len
while(k < len) {
var kValue, mappedValue;
// a. Let Pk be ToString(k).
// This is implicit for LHS operands of the in operator
// b. Let kPresent be the result of calling the HasProperty internal method of O with argument Pk.
// This step can be combined with c
// c. If kPresent is true, then
if (k in O) {
// i. Let kValue be the result of calling the Get internal method of O with argument Pk.
kValue = O[ k ];
// ii. Let mappedValue be the result of calling the Call internal method of callback
// with T as the this value and argument list containing kValue, k, and O.
mappedValue = callback.call(T, kValue, k, O);
// iii. Call the DefineOwnProperty internal method of A with arguments
// Pk, Property Descriptor {Value: mappedValue, : true, Enumerable: true, Configurable: true},
// and false.
// In browsers that support Object.defineProperty, use the following:
// Object.defineProperty(A, Pk, { value: mappedValue, writable: true, enumerable: true, configurable: true });
// For best browser support, use the following:
A[ k ] = mappedValue;
}
// d. Increase k by 1.
k++;
}
// 9. return A
return A;
};
}
// From https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/indexOf
if (!Array.prototype.indexOf) {
Array.prototype.indexOf = function (searchElement, fromIndex) {
if ( this === undefined || this === null ) {
throw new TypeError( '"this" is null or not defined' );
}
var length = this.length >>> 0; // Hack to convert object.length to a UInt32
fromIndex = +fromIndex || 0;
if (Math.abs(fromIndex) === Infinity) {
fromIndex = 0;
}
if (fromIndex < 0) {
fromIndex += length;
if (fromIndex < 0) {
fromIndex = 0;
}
}
for (;fromIndex < length; fromIndex++) {
if (this[fromIndex] === searchElement) {
return fromIndex;
}
}
return -1;
};
}
// Based on https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/isArray
if (! Array.isArray) {
Array.isArray = function(obj) {
return Object.prototype.toString.call(obj) === "[object Array]";
};
}
// https://github.com/ttaubert/node-arraybuffer-slice
// (c) 2013 Tim Taubert <tim@timtaubert.de>
// arraybuffer-slice may be freely distributed under the MIT license.
"use strict";
if (typeof ArrayBuffer !== 'undefined' && !ArrayBuffer.prototype.slice) {
ArrayBuffer.prototype.slice = function (begin, end) {
begin = (begin|0) || 0;
var num = this.byteLength;
end = end === (void 0) ? num : (end|0);
// Handle negative values.
if (begin < 0) begin += num;
if (end < 0) end += num;
if (num === 0 || begin >= num || begin >= end) {
return new ArrayBuffer(0);
}
var length = Math.min(num - begin, end - begin);
var target = new ArrayBuffer(length);
var targetArray = new Uint8Array(target);
targetArray.set(new Uint8Array(this, begin, length));
return target;
};
}