unexpected/lib/shim.js

Minimalistic BDD assertion toolkit inspired by [expect.js](https://github.com/LearnBoost/expect.js)

var shim;
try {
    shim = require('./shim-es4');
} catch (e) {
    // Probably excluded via browserify -u lib/shim-es4.js
    shim = {};
}
var prototypes = {
    bind: Function.prototype.bind,
    every: Array.prototype.every,
    some: Array.prototype.some,
    indexOf: Array.prototype.indexOf,
    forEach: Array.prototype.forEach,
    map: Array.prototype.map,
    filter: Array.prototype.filter,
    reduce: Array.prototype.reduce,
    trim: String.prototype.trim
};

function createShimMethod(key) {
    shim[key] = function (obj) {
        var args = Array.prototype.slice.call(arguments, 1);
        return prototypes[key].apply(obj, args);
    };
}

for (var key in prototypes) {
    if (prototypes.hasOwnProperty(key) && prototypes[key]) {
        createShimMethod(key);
    }
}

if (!shim.bind) {
    shim.bind = function (fn, scope) {
        return function () {
            return fn.apply(scope, arguments);
        };
    };
}

if (Object.keys) {
    shim['getKeys'] = Object.keys;
}

if ('object' === typeof JSON && JSON.parse && JSON.stringify) {
    shim['JSON'] = JSON;
}

module.exports = shim;