removeListener.js

var simpleEvents= require('nodeunit').testCase;

var file = '../../lib/eventemitter2';

module.exports = simpleEvents({

  setUp: function (callback) {
    var EventEmitter2;

    if(typeof require !== 'undefined') {
      EventEmitter2 = require(file).EventEmitter2;
    }
    else {
      EventEmitter2 = window.EventEmitter2;
    }

    this.emitter = new EventEmitter2;
    callback();
  },

  tearDown: function (callback) {
    //clean up?
    callback();
  },

  'removeListener1. adding 1, removing 1' : function (test) {
    var emitter = this.emitter,
        type = 'remove',
        listeners;

    var f = function f() {
      test.ok(true, 'event was raised');
    };

    emitter.on(type, f);
    listeners = emitter.listeners(type);
    test.equal(listeners.length, 1, 'should only have 1');

    //remove
    emitter.removeListener(type, f);
    listeners = emitter.listeners(type);
    test.equal(listeners.length, 0, 'should be 0');

    test.expect(2);
    test.done();
  },

  'removeListener2. adding 2, removing 1' : function (test) {
    var emitter = this.emitter,
        type = 'remove',
        listeners;

    var f = function f() {
      test.ok(true, 'event was raised');
    };

    emitter.on(type, f);
    emitter.on(type, f);
    listeners = emitter.listeners(type);
    test.equal(listeners.length, 2, 'should only have 2');

    //remove
    emitter.removeListener(type, f);
    listeners = emitter.listeners(type);
    test.equal(listeners.length, 1, 'should be 1');

    test.expect(2);
    test.done();
  },

  'removeListener3. adding 3, removing 1' : function (test) {
    var emitter = this.emitter,
        type = 'remove',
        listeners;

    var f = function f() {
      test.ok(true, 'event was raised');
    };

    emitter.on(type, f);
    emitter.on(type, f);
    emitter.on(type, f);
    listeners = emitter.listeners(type);
    test.equal(listeners.length, 3, 'should only have 3');

    //remove
    emitter.removeListener(type, f);
    listeners = emitter.listeners(type);
    test.equal(listeners.length, 2, 'should be 2');

    test.expect(2);
    test.done();
  },

  'removeListener4. should error if we don\'t pass in a function' : function (test) {
    var emitter = this.emitter,
        type = 'remove',
        listeners;

    var f = function f() {
      test.ok(true, 'event was raised');
    };

    emitter.on(type, f);
    listeners = emitter.listeners(type);
    test.equal(listeners.length, 1, 'should only have 1');

    //remove
    test.throws(function () {emitter.removeListener(type, type)}, Error, 'should throw an Error');
    listeners = emitter.listeners(type);
    test.equal(listeners.length, 1, 'should be 1');

    test.expect(3);
    test.done();
  },

  'removeListener5. removing a different function, should not remove' : function (test) {
    var emitter = this.emitter,
        type = 'remove',
        listeners;

    var f = function f() {
      test.ok(true, 'event was raised');
    };
    var g = function g() {
      test.ok(true, 'event was raised');
    };

    emitter.on(type, f);
    listeners = emitter.listeners(type);
    test.equal(listeners.length, 1, 'should only have 1');

    //remove
    emitter.removeListener(type, g);
    listeners = emitter.listeners(type);
    test.equal(listeners.length, 1, 'should be 1');

    test.expect(2);
    test.done();
  },

  'removeListener6. removing all functions' : function (test) {
    var emitter = this.emitter,
        type = 'remove',
        listeners;

    var f = function f() {
      test.ok(true, 'event was raised');
    };
    for (var i = 0; i < 10; i++) {
      emitter.on(type, f);
    }
    listeners = emitter.listeners(type);
    test.equal(listeners.length, 10, 'should only have 10');

    emitter.removeListener(type, f);
    listeners = emitter.listeners(type);
    test.equal(listeners.length, 9, 'should be 9');
    emitter.removeAllListeners(type);
    listeners = emitter.listeners(type);
    test.equal(listeners.length, 0, 'should be 0');

    test.expect(3);
    test.done();
  },

  'removeListener7. removing different event, should not remove' : function (test) {
    var emitter = this.emitter,
        type = 'remove',
        listeners;

    var f = function f() {
      test.ok(true, 'event was raised');
    };

    for (var i = 0; i < 10; i++) {
      emitter.on(type, f);
    }
    listeners = emitter.listeners(type);
    test.equal(listeners.length, 10, 'should only have 10');

    emitter.removeListener(type+type, f);
    listeners = emitter.listeners(type);
    test.equal(listeners.length, 10, 'should be 10');

    emitter.removeAllListeners(type+type);
    listeners = emitter.listeners(type);
    test.equal(listeners.length, 10, 'should be 10');

    emitter.removeAllListeners(type);
    listeners = emitter.listeners(type);
    test.equal(listeners.length, 0, 'should be 0');

    test.expect(4);
    test.done();
  },


});