gulpfile.js
function waitFor(stream) {
	return new Promise((resolve, reject) => {
		stream.on('end', resolve);
		stream.on('error', reject);
	});
}
function waitFor(stream) {
	return new Promise((resolve, reject) => {
		stream.on('end', resolve);
		stream.on('error', reject);
	});
}
function waitFor ( stream ) { return new Promise ( ( resolve , reject ) => { stream . on ( 'end' , resolve ) ; stream . on ( 'error' , reject ) ; } ) ; }
Waits for the given ReadableStream
Waits for the given ReadableStream