atcheck/lsscanner/new_ubuntu/node_modules_win/p-locate/index.js

35 lines
1.0 KiB
JavaScript
Raw Normal View History

2019-12-16 18:42:21 +01:00
'use strict';
const pLimit = require('p-limit');
class EndError extends Error {
constructor(value) {
super();
this.value = value;
}
}
// The input can also be a promise, so we `Promise.resolve()` it
const testElement = (el, tester) => Promise.resolve(el).then(tester);
// The input can also be a promise, so we `Promise.all()` them both
const finder = el => Promise.all(el).then(val => val[1] === true && Promise.reject(new EndError(val[0])));
module.exports = (iterable, tester, opts) => {
opts = Object.assign({
concurrency: Infinity,
preserveOrder: true
}, opts);
const limit = pLimit(opts.concurrency);
// Start all the promises concurrently with optional limit
const items = [...iterable].map(el => [el, limit(testElement, el, tester)]);
// Check the promises either serially or concurrently
const checkLimit = pLimit(opts.preserveOrder ? 1 : Infinity);
return Promise.all(items.map(el => checkLimit(finder, el)))
.then(() => {})
.catch(err => err instanceof EndError ? err.value : Promise.reject(err));
};