index.d.ts 1.82 KB
declare namespace pLocate {
	interface Options {
		/**
		Number of concurrently pending promises returned by `tester`. Minimum: `1`.

		@default Infinity
		*/
		readonly concurrency?: number;

		/**
		Preserve `input` order when searching.

		Disable this to improve performance if you don't care about the order.

		@default true
		*/
		readonly preserveOrder?: boolean;
	}
}

declare const pLocate: {
	/**
	Get the first fulfilled promise that satisfies the provided testing function.

	@param input - An iterable of promises/values to test.
	@param tester - This function will receive resolved values from `input` and is expected to return a `Promise<boolean>` or `boolean`.
	@returns A `Promise` that is fulfilled when `tester` resolves to `true` or the iterable is done, or rejects if any of the promises reject. The fulfilled value is the current iterable value or `undefined` if `tester` never resolved to `true`.

	@example
	```
	import pathExists = require('path-exists');
	import pLocate = require('p-locate');

	const files = [
		'unicorn.png',
		'rainbow.png', // Only this one actually exists on disk
		'pony.png'
	];

	(async () => {
		const foundPath = await pLocate(files, file => pathExists(file));

		console.log(foundPath);
		//=> 'rainbow'
	})();
	```
	*/
	<ValueType>(
		input: Iterable<PromiseLike<ValueType> | ValueType>,
		tester: (element: ValueType) => PromiseLike<boolean> | boolean,
		options?: pLocate.Options
	): Promise<ValueType | undefined>;

	// TODO: Remove this for the next major release, refactor the whole definition to:
	// declare function pLocate<ValueType>(
	// 	input: Iterable<PromiseLike<ValueType> | ValueType>,
	// 	tester: (element: ValueType) => PromiseLike<boolean> | boolean,
	// 	options?: pLocate.Options
	// ): Promise<ValueType | undefined>;
	// export = pLocate;
	default: typeof pLocate;
};

export = pLocate;