my-idlers/node_modules/events/tests/events-once.js

235 lines
6.0 KiB
JavaScript
Raw Normal View History

'use strict';
var common = require('./common');
var EventEmitter = require('../').EventEmitter;
var once = require('../').once;
var has = require('has');
var assert = require('assert');
function Event(type) {
this.type = type;
}
function EventTargetMock() {
this.events = {};
this.addEventListener = common.mustCall(this.addEventListener);
this.removeEventListener = common.mustCall(this.removeEventListener);
}
EventTargetMock.prototype.addEventListener = function addEventListener(name, listener, options) {
if (!(name in this.events)) {
this.events[name] = { listeners: [], options: options || {} }
}
this.events[name].listeners.push(listener);
};
EventTargetMock.prototype.removeEventListener = function removeEventListener(name, callback) {
if (!(name in this.events)) {
return;
}
var event = this.events[name];
var stack = event.listeners;
for (var i = 0, l = stack.length; i < l; i++) {
if (stack[i] === callback) {
stack.splice(i, 1);
if (stack.length === 0) {
delete this.events[name];
}
return;
}
}
};
EventTargetMock.prototype.dispatchEvent = function dispatchEvent(arg) {
if (!(arg.type in this.events)) {
return true;
}
var event = this.events[arg.type];
var stack = event.listeners.slice();
for (var i = 0, l = stack.length; i < l; i++) {
stack[i].call(null, arg);
if (event.options.once) {
this.removeEventListener(arg.type, stack[i]);
}
}
return !arg.defaultPrevented;
};
function onceAnEvent() {
var ee = new EventEmitter();
process.nextTick(function () {
ee.emit('myevent', 42);
});
return once(ee, 'myevent').then(function (args) {
var value = args[0]
assert.strictEqual(value, 42);
assert.strictEqual(ee.listenerCount('error'), 0);
assert.strictEqual(ee.listenerCount('myevent'), 0);
});
}
function onceAnEventWithTwoArgs() {
var ee = new EventEmitter();
process.nextTick(function () {
ee.emit('myevent', 42, 24);
});
return once(ee, 'myevent').then(function (value) {
assert.strictEqual(value.length, 2);
assert.strictEqual(value[0], 42);
assert.strictEqual(value[1], 24);
});
}
function catchesErrors() {
var ee = new EventEmitter();
var expected = new Error('kaboom');
var err;
process.nextTick(function () {
ee.emit('error', expected);
});
return once(ee, 'myevent').then(function () {
throw new Error('should reject')
}, function (err) {
assert.strictEqual(err, expected);
assert.strictEqual(ee.listenerCount('error'), 0);
assert.strictEqual(ee.listenerCount('myevent'), 0);
});
}
function stopListeningAfterCatchingError() {
var ee = new EventEmitter();
var expected = new Error('kaboom');
var err;
process.nextTick(function () {
ee.emit('error', expected);
ee.emit('myevent', 42, 24);
});
// process.on('multipleResolves', common.mustNotCall());
return once(ee, 'myevent').then(common.mustNotCall, function (err) {
// process.removeAllListeners('multipleResolves');
assert.strictEqual(err, expected);
assert.strictEqual(ee.listenerCount('error'), 0);
assert.strictEqual(ee.listenerCount('myevent'), 0);
});
}
function onceError() {
var ee = new EventEmitter();
var expected = new Error('kaboom');
process.nextTick(function () {
ee.emit('error', expected);
});
var promise = once(ee, 'error');
assert.strictEqual(ee.listenerCount('error'), 1);
return promise.then(function (args) {
var err = args[0]
assert.strictEqual(err, expected);
assert.strictEqual(ee.listenerCount('error'), 0);
assert.strictEqual(ee.listenerCount('myevent'), 0);
});
}
function onceWithEventTarget() {
var et = new EventTargetMock();
var event = new Event('myevent');
process.nextTick(function () {
et.dispatchEvent(event);
});
return once(et, 'myevent').then(function (args) {
var value = args[0];
assert.strictEqual(value, event);
assert.strictEqual(has(et.events, 'myevent'), false);
});
}
function onceWithEventTargetError() {
var et = new EventTargetMock();
var error = new Event('error');
process.nextTick(function () {
et.dispatchEvent(error);
});
return once(et, 'error').then(function (args) {
var err = args[0];
assert.strictEqual(err, error);
assert.strictEqual(has(et.events, 'error'), false);
});
}
function prioritizesEventEmitter() {
var ee = new EventEmitter();
ee.addEventListener = assert.fail;
ee.removeAllListeners = assert.fail;
process.nextTick(function () {
ee.emit('foo');
});
return once(ee, 'foo');
}
var allTests = [
onceAnEvent(),
onceAnEventWithTwoArgs(),
catchesErrors(),
stopListeningAfterCatchingError(),
onceError(),
onceWithEventTarget(),
onceWithEventTargetError(),
prioritizesEventEmitter()
];
var hasBrowserEventTarget = false;
try {
hasBrowserEventTarget = typeof (new window.EventTarget().addEventListener) === 'function' &&
new window.Event('xyz').type === 'xyz';
} catch (err) {}
if (hasBrowserEventTarget) {
var onceWithBrowserEventTarget = function onceWithBrowserEventTarget() {
var et = new window.EventTarget();
var event = new window.Event('myevent');
process.nextTick(function () {
et.dispatchEvent(event);
});
return once(et, 'myevent').then(function (args) {
var value = args[0];
assert.strictEqual(value, event);
assert.strictEqual(has(et.events, 'myevent'), false);
});
}
var onceWithBrowserEventTargetError = function onceWithBrowserEventTargetError() {
var et = new window.EventTarget();
var error = new window.Event('error');
process.nextTick(function () {
et.dispatchEvent(error);
});
return once(et, 'error').then(function (args) {
var err = args[0];
assert.strictEqual(err, error);
assert.strictEqual(has(et.events, 'error'), false);
});
}
common.test.comment('Testing with browser built-in EventTarget');
allTests.push([
onceWithBrowserEventTarget(),
onceWithBrowserEventTargetError()
]);
}
module.exports = Promise.all(allTests);