55 lines
1.6 KiB
TypeScript
55 lines
1.6 KiB
TypeScript
/**
|
|
* @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>}
|
|
*/
|
|
export const waitForEvent = (target: EventTarget, eventName: string) => {
|
|
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.
|
|
*/
|
|
export const emittedOnce = (emitter: NodeJS.EventEmitter, eventName: string, trigger?: () => void) => {
|
|
return emittedNTimes(emitter, eventName, 1, trigger).then(([result]) => result);
|
|
};
|
|
|
|
export const emittedNTimes = async (emitter: NodeJS.EventEmitter, eventName: string, times: number, trigger?: () => void) => {
|
|
const events: any[][] = [];
|
|
const p = new Promise<any[][]>(resolve => {
|
|
const handler = (...args: any[]) => {
|
|
events.push(args);
|
|
if (events.length === times) {
|
|
emitter.removeListener(eventName, handler);
|
|
resolve(events);
|
|
}
|
|
};
|
|
emitter.on(eventName, handler);
|
|
});
|
|
if (trigger) {
|
|
await Promise.resolve(trigger());
|
|
}
|
|
return p;
|
|
};
|
|
|
|
export const emittedUntil = async (emitter: NodeJS.EventEmitter, eventName: string, untilFn: Function) => {
|
|
const p = new Promise<any[]>(resolve => {
|
|
const handler = (...args: any[]) => {
|
|
if (untilFn(...args)) {
|
|
emitter.removeListener(eventName, handler);
|
|
resolve(args);
|
|
}
|
|
};
|
|
emitter.on(eventName, handler);
|
|
});
|
|
return p;
|
|
};
|