electron/spec/events-helpers.js

43 строки
1.0 KiB
JavaScript

/**
* @fileoverview A set of helper functions to make it easier to work
* with events in async/await manner.
*/
/**
* @param {!EventTarget} target
* @param {string} eventName
* @return {!Promise<!Event>}
*/
const waitForEvent = (target, eventName) => {
return new Promise(resolve => {
target.addEventListener(eventName, resolve, { once: true })
})
}
/**
* @param {!EventEmitter} emitter
* @param {string} eventName
* @return {!Promise<!Array>} With Event as the first item.
*/
const emittedOnce = (emitter, eventName) => {
return emittedNTimes(emitter, eventName, 1).then(([result]) => result)
}
const emittedNTimes = (emitter, eventName, times) => {
const events = []
return new Promise(resolve => {
const handler = (...args) => {
events.push(args)
if (events.length === times) {
emitter.removeListener(eventName, handler)
resolve(events)
}
}
emitter.on(eventName, handler)
})
}
exports.emittedOnce = emittedOnce
exports.emittedNTimes = emittedNTimes
exports.waitForEvent = waitForEvent