7423028fea
* add tslint rule to disallow lodash.isUndefined * add tslint rule to disallow lodash.isNull * apply fixes
20 lines
989 B
TypeScript
20 lines
989 B
TypeScript
import * as _ from 'lodash';
|
|
|
|
/**
|
|
* Transforms callback-based function -- func(arg1, arg2 .. argN, callback) -- into an ES6-compatible Promise.
|
|
* Promisify provides a default callback of the form (error, result) and rejects when `error` is not null. You can also
|
|
* supply thisArg object as the second argument which will be passed to `apply`.
|
|
*/
|
|
// HACK: This can't be properly typed without variadic kinds https://github.com/Microsoft/TypeScript/issues/5453
|
|
export function promisify<T>(originalFn: (...args: any[]) => void, thisArg?: any): (...callArgs: any[]) => Promise<T> {
|
|
const promisifiedFunction = async (...callArgs: any[]): Promise<T> => {
|
|
return new Promise<T>((resolve, reject) => {
|
|
const callback = (err: Error | null, data?: T) => {
|
|
err === null || err === undefined ? resolve(data) : reject(err);
|
|
};
|
|
originalFn.apply(thisArg, [...callArgs, callback]);
|
|
});
|
|
};
|
|
return promisifiedFunction;
|
|
}
|