node/test/parallel/test-event-emitter-listeners.js
Rich Trott 359766b2c3 benchmark,doc,lib,test: prepare for padding lint rule
Upcoming lint rule will require a blank line between consecutive
functions. Add it in the places where we don't have it already.

PR-URL: https://github.com/nodejs/node/pull/30696
Reviewed-By: Michaël Zasso <targos@protonmail.com>
Reviewed-By: Gireesh Punathil <gpunathi@in.ibm.com>
Reviewed-By: Trivikram Kamat <trivikr.dev@gmail.com>
Reviewed-By: Gus Caplan <me@gus.host>
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Richard Lau <riclau@uk.ibm.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Denys Otrishko <shishugi@gmail.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
2019-11-30 06:28:29 -08:00

125 lines
4.0 KiB
JavaScript

// Copyright Joyent, Inc. and other Node contributors.
//
// Permission is hereby granted, free of charge, to any person obtaining a
// copy of this software and associated documentation files (the
// "Software"), to deal in the Software without restriction, including
// without limitation the rights to use, copy, modify, merge, publish,
// distribute, sublicense, and/or sell copies of the Software, and to permit
// persons to whom the Software is furnished to do so, subject to the
// following conditions:
//
// The above copyright notice and this permission notice shall be included
// in all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN
// NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
// DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
// OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
// USE OR OTHER DEALINGS IN THE SOFTWARE.
'use strict';
require('../common');
const assert = require('assert');
const events = require('events');
function listener() {}
function listener2() {}
function listener3() {
return 0;
}
function listener4() {
return 1;
}
{
const ee = new events.EventEmitter();
ee.on('foo', listener);
const fooListeners = ee.listeners('foo');
assert.deepStrictEqual(ee.listeners('foo'), [listener]);
ee.removeAllListeners('foo');
assert.deepStrictEqual(ee.listeners('foo'), []);
assert.deepStrictEqual(fooListeners, [listener]);
}
{
const ee = new events.EventEmitter();
ee.on('foo', listener);
const eeListenersCopy = ee.listeners('foo');
assert.deepStrictEqual(eeListenersCopy, [listener]);
assert.deepStrictEqual(ee.listeners('foo'), [listener]);
eeListenersCopy.push(listener2);
assert.deepStrictEqual(ee.listeners('foo'), [listener]);
assert.deepStrictEqual(eeListenersCopy, [listener, listener2]);
}
{
const ee = new events.EventEmitter();
ee.on('foo', listener);
const eeListenersCopy = ee.listeners('foo');
ee.on('foo', listener2);
assert.deepStrictEqual(ee.listeners('foo'), [listener, listener2]);
assert.deepStrictEqual(eeListenersCopy, [listener]);
}
{
const ee = new events.EventEmitter();
ee.once('foo', listener);
assert.deepStrictEqual(ee.listeners('foo'), [listener]);
}
{
const ee = new events.EventEmitter();
ee.on('foo', listener);
ee.once('foo', listener2);
assert.deepStrictEqual(ee.listeners('foo'), [listener, listener2]);
}
{
const ee = new events.EventEmitter();
ee._events = undefined;
assert.deepStrictEqual(ee.listeners('foo'), []);
}
{
class TestStream extends events.EventEmitter {}
const s = new TestStream();
assert.deepStrictEqual(s.listeners('foo'), []);
}
{
const ee = new events.EventEmitter();
ee.on('foo', listener);
const wrappedListener = ee.rawListeners('foo');
assert.strictEqual(wrappedListener.length, 1);
assert.strictEqual(wrappedListener[0], listener);
assert.notStrictEqual(wrappedListener, ee.rawListeners('foo'));
ee.once('foo', listener);
const wrappedListeners = ee.rawListeners('foo');
assert.strictEqual(wrappedListeners.length, 2);
assert.strictEqual(wrappedListeners[0], listener);
assert.notStrictEqual(wrappedListeners[1], listener);
assert.strictEqual(wrappedListeners[1].listener, listener);
assert.notStrictEqual(wrappedListeners, ee.rawListeners('foo'));
ee.emit('foo');
assert.strictEqual(wrappedListeners.length, 2);
assert.strictEqual(wrappedListeners[1].listener, listener);
}
{
const ee = new events.EventEmitter();
ee.once('foo', listener3);
ee.on('foo', listener4);
const rawListeners = ee.rawListeners('foo');
assert.strictEqual(rawListeners.length, 2);
assert.strictEqual(rawListeners[0](), 0);
const rawListener = ee.rawListeners('foo');
assert.strictEqual(rawListener.length, 1);
assert.strictEqual(rawListener[0](), 1);
}