Wait for a condition to be true
Can be useful for polling.
$ npm install p-wait-for
const pWaitFor = require('p-wait-for');
const pathExists = require('path-exists');
(async () => {
await pWaitFor(() => pathExists('unicorn.png'));
console.log('Yay! The file now exists.');
})();
Returns a Promise
that resolves when condition
returns true
. Rejects if condition
throws or returns a Promise
that rejects.
Type: Function
Expected to return Promise<boolean> | boolean
.
Type: object
Type: number
Default: 20
Number of milliseconds to wait before retrying condition
.
Type: number
Default: Infinity
Number of milliseconds to wait before automatically rejecting.
Type: boolean
Default: true
Whether to run the check immediately rather than starting by waiting interval
milliseconds.
Useful for when the check, if run immediately, would likely return false
. In this scenario, set leadingCheck
to false
.