p-timeout/index.js

41 lines
892 B
JavaScript

'use strict';
const pFinally = require('p-finally');
class TimeoutError extends Error {
constructor(message) {
super(message);
this.name = 'TimeoutError';
}
}
module.exports = (promise, ms, fallback) => new Promise((resolve, reject) => {
if (typeof ms !== 'number' && ms >= 0) {
throw new TypeError('Expected `ms` to be a positive number');
}
const timer = setTimeout(() => {
if (typeof fallback === 'function') {
resolve(fallback());
return;
}
const message = typeof fallback === 'string' ? fallback : `Promise timed out after ${ms} milliseconds`;
const err = fallback instanceof Error ? fallback : new TimeoutError(message);
if (typeof promise.cancel === 'function') {
promise.cancel(err);
}
reject(err);
}, ms);
pFinally(
promise.then(resolve, reject),
() => {
clearTimeout(timer);
}
);
});
module.exports.TimeoutError = TimeoutError;