| 'use strict'; | 
 |  | 
 | var common = require('./common'); | 
 | var EventEmitter = require('../'); | 
 | var assert = require('assert'); | 
 |  | 
 | var ee = new EventEmitter(); | 
 | var foo = Symbol('foo'); | 
 | var listener = common.mustCall(); | 
 |  | 
 | ee.on(foo, listener); | 
 | assert.strictEqual(ee.listeners(foo).length, 1); | 
 | assert.strictEqual(ee.listeners(foo)[0], listener); | 
 |  | 
 | ee.emit(foo); | 
 |  | 
 | ee.removeAllListeners(); | 
 | assert.strictEqual(ee.listeners(foo).length, 0); | 
 |  | 
 | ee.on(foo, listener); | 
 | assert.strictEqual(ee.listeners(foo).length, 1); | 
 | assert.strictEqual(ee.listeners(foo)[0], listener); | 
 |  | 
 | ee.removeListener(foo, listener); | 
 | assert.strictEqual(ee.listeners(foo).length, 0); |