'use strict';
|
|
|
|
var common = require('./common');
|
|
var EventEmitter = require('../');
|
|
var assert = require('assert');
|
|
|
|
var myEE = new EventEmitter();
|
|
var m = 0;
|
|
// This one comes last.
|
|
myEE.on('foo', common.mustCall(function () {
|
|
assert.strictEqual(m, 2);
|
|
}));
|
|
|
|
// This one comes second.
|
|
myEE.prependListener('foo', common.mustCall(function () {
|
|
assert.strictEqual(m++, 1);
|
|
}));
|
|
|
|
// This one comes first.
|
|
myEE.prependOnceListener('foo',
|
|
common.mustCall(function () {
|
|
assert.strictEqual(m++, 0);
|
|
}));
|
|
|
|
myEE.emit('foo');
|
|
|
|
// Verify that the listener must be a function
|
|
assert.throws(function () {
|
|
var ee = new EventEmitter();
|
|
ee.prependOnceListener('foo', null);
|
|
}, 'TypeError: The "listener" argument must be of type Function. Received type object');
|