webpack/test/browsertest/nodetests/simple/test-event-emitter-once.js

50 lines
1.7 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.
var common = require('../common');
var assert = require('assert');
var events = require('events');
var e = new events.EventEmitter();
var times_hello_emited = 0;
e.once('hello', function(a, b) {
times_hello_emited++;
});
e.emit('hello', 'a', 'b');
e.emit('hello', 'a', 'b');
e.emit('hello', 'a', 'b');
e.emit('hello', 'a', 'b');
var remove = function() {
assert.fail(1, 0, 'once->foo should not be emitted', '!');
};
e.once('foo', remove);
e.removeListener('foo', remove);
e.emit('foo');
process.on('exit', function() {
assert.equal(1, times_hello_emited);
});