native js event listener

eventListener.js

(function () {
    'use strict';
    var fo = window.fo = window.fo || {},
        eventHandler = fo.eventHandler = fo.eventHandler || {};

    eventHandler.events = {};

    eventHandler.publish = function (event, data) {
        var events = event.split(' '),
            key, func;
        for (key in events) {
            if (eventHandler.events.hasOwnProperty(events[key])) {
                if (Object.prototype.toString.call(eventHandler.events[events[key]]) === '[object Array]') {
                    for (func in eventHandler.events[events[key]]) {
                        eventHandler.events[events[key]][func].call(this, events[key], data);
                    }
                }
            }
        }
    };

    eventHandler.subscribe = function (event, cb) {
        var events = event.split(' '),
            key, k, arr;
        for (key in events) {
            if (!eventHandler.events.hasOwnProperty(events[key])) {
                if (Object.prototype.toString.call(cb) === '[object Array]' || typeof cb === 'function') {
                    eventHandler.events[events[key]] = typeof cb === 'function' ? [cb] : cb;
                }
            } else {
                if (Object.prototype.toString.call(eventHandler.events[events[key]]) === '[object Array]') {
                    arr = typeof cb === 'function' ? [cb] : cb;
                    for (k in arr) {
                        if (eventHandler.events[events[key]].toString().indexOf(arr[k]) <= -1) {
                            eventHandler.events[events[key]].push(arr[k]);
                        }
                    }
                }
            }
        }
    };

    eventHandler.unsubscribe = function (event) {
        var events = event.split(' '),
            key;
        for (key in events) {
            if (eventHandler.events.hasOwnProperty(events[key])) {
                delete eventHandler.events[events[key]];
            }
        }
    };
}());

eventListener.spec.js

/** jasmine test **/
describe("event listener", function () {
    it("fo should be object", function () {
        expect(typeof (fo)).toBe('object');
    });
    it("fo.eventHandler.events should be object", function () {
        expect(typeof (fo.eventHandler.events)).toBe('object');
    });
    it("fo.eventHandler.publish should be function", function () {
        expect(typeof (fo.eventHandler.publish)).toBe('function');
    });
    describe("publish", function () {
        it("fo.eventHandler.publish should call its callback", function () {        
            var eventHandler = fo.eventHandler;
            spyOn(eventHandler, 'subscribe').andCallThrough();
            spyOn(eventHandler, 'publish').andCallThrough();
            eventHandler.subscribe('key', function (trigger, data) {
                console.log('data');
            });        
            expect(eventHandler.subscribe).toHaveBeenCalled();
            eventHandler.publish('key');
            expect(eventHandler.publish).toHaveBeenCalled();
            fo.eventHandler.unsubscribe('key');
        });
        it("fo.eventHandler.publish should accept an array of callbacks", function () {        
            var eventHandler = fo.eventHandler,
                arr = [];
            spyOn(eventHandler, 'subscribe').andCallThrough();
            spyOn(eventHandler, 'publish').andCallThrough();
            eventHandler.subscribe('key', [

                function (trigger, data) {
                    arr.push('1');
                },
                function (trigger, data) {
                    arr.push('2');
                }
            ]);
            eventHandler.publish('key');
            expect(eventHandler.publish).toHaveBeenCalled();
            expect(eventHandler.subscribe).toHaveBeenCalled();
            expect(arr.length).toBe(2);
            expect(fo.eventHandler.subscribers.key.length).toBe(2);
            fo.eventHandler.unsubscribe('key');
        });
    });
    describe("subscribe", function () {
        it("fo.eventHandler.subscribe should be function", function () {
            expect(typeof (fo.eventHandler.subscribe)).toBe('function');
        });
        it("fo.eventHandler.subscribe function should put event 'key' into fo.eventHandler.events", function () {
            fo.eventHandler.subscribe('key', function (trigger, data) {});
            expect(fo.eventHandler.subscribers.key).toBeDefined();
            fo.eventHandler.unsubscribe('key');
        });
        it("fo.eventHandler.subscribe function should put event 'key1' and 'key2' into fo.eventHandler.events", function () {
            fo.eventHandler.subscribe('key1 key2', function (trigger, data) {});
            expect(fo.eventHandler.subscribers.key1).toBeDefined();
            expect(fo.eventHandler.subscribers.key2).toBeDefined();
            fo.eventHandler.unsubscribe('key1 key2');
            expect(fo.eventHandler.subscribers.key1).not.toBeDefined();
            expect(fo.eventHandler.subscribers.key2).not.toBeDefined();
        });
        it("fo.eventHandler.subscribe should take an array or a function as a callback", function () {
            fo.eventHandler.subscribe('key', function (trigger, data) {
                console.log(data);
            });
            expect(fo.eventHandler.subscribers.key).toBeDefined();
            fo.eventHandler.unsubscribe('key');
            fo.eventHandler.subscribe('key', [

                function (trigger, data) {
                    console.log(data);
                },
                function (trigger, data) {
                    console.log(trigger)
                }
            ]);
            expect(fo.eventHandler.subscribers.key).toBeDefined();
            fo.eventHandler.unsubscribe('key');
        });
        it("fo.eventHandler.subscribe function should add events to 'key' in fo.eventHandler.events", function () {
            fo.eventHandler.subscribe('key', function (a, b) {
                console.log(data);
            });
            expect(fo.eventHandler.subscribers.key.length).toBe(1);
            fo.eventHandler.subscribe('key', function (c, d) {
                console.log(data);
            });
            expect(fo.eventHandler.subscribers.key.length).toBe(2);
            fo.eventHandler.subscribe('key', [

                function (e, f) {
                    console.log(data);
                }
            ]);
            expect(fo.eventHandler.subscribers.key.length).toBe(3);
            fo.eventHandler.subscribe('key', [

                function (g, h) {
                    console.log(data);
                },
                function (i, j) {
                    console.log(data);
                },
                function (i, j) {
                    console.log(data);
                }
            ]);
            expect(fo.eventHandler.subscribers.key.length).toBe(5);
            fo.eventHandler.unsubscribe('key');
        });
    });
    describe("unsubscribe", function () {
        it("fo.eventHandler.unsubscribe should be function", function () {
            expect(typeof (fo.eventHandler.unsubscribe)).toBe('function');
        });
        it("fo.eventHandler.unsubscribe function should remove event 'key' from fo.eventHandler.events", function () {
            fo.eventHandler.subscribe('key', function (trigger, data) {
                console.log(data);
            });
            fo.eventHandler.unsubscribe('key');
            expect(fo.eventHandler.events.key).not.toBeDefined();
        });
        it("fo.eventHandler.unsubscribe function should remove events 'key1' and 'key2' from fo.eventHandler.events", function () {
            fo.eventHandler.subscribe('key1 key2', function (trigger, data) {});
            expect(fo.eventHandler.subscribers.key1).toBeDefined();
            expect(fo.eventHandler.subscribers.key2).toBeDefined();
            fo.eventHandler.unsubscribe('key1 key2');
            expect(fo.eventHandler.subscribers.key1).not.toBeDefined();
            expect(fo.eventHandler.subscribers.key2).not.toBeDefined();
        });
    });
});