simple mocker

gistfile1.js

"use strict";
var mocker = function(self){
    return {
        "mocked":{},
 
        "mock":function(name){
            var current = this.mocked[name];
            if(current != null) {
                return current;
            }
 
            var root = this;
            return this.mocked[name] = current =  {
                "origin":null,
 
                "target":null,
 
                "with":function(target){
                    this.origin = self[name];
                    self[name] = this.target = target;
                    return this;
                },
 
                "swap":function(name){
                    var current = root.mocked[name];
                    if( current != null ){
                        return this.with(this.origin);
                    }
                    return this;
                },
 
                "undo":function(){
                    self[name] = this.origin;
                    delete root.mocked[name];
                    return this;
                },
 
                "reset":function(){
                    var old = root.mocked;
                    root.mocked = {};
                    for(var item in old){
                        old[item].undo();
                    }
 
                    return this;
                }
            };
        }
    }
};