defer-close/index.ts

A lightweight utility for adding JavaScript's Disposable and AsyncDisposable interfaces to any object

export default function deferClose<T extends object>(
  obj: T,
  fn: (obj: T) => Promise<any>
): T & AsyncDisposable;
export default function deferClose<T extends object>(
  obj: T,
  fn: (obj: T) => any
): T & Disposable;
export default function deferClose<T extends object>(
  obj: T,
  fn: (obj: T) => any
): T & Disposable & AsyncDisposable {
  const r = Object.assign(obj, {
    [Symbol.dispose]() {
      fn(obj);
    },
    async [Symbol.asyncDispose]() {
      await fn(obj);
    },
  });
  return r as T & Disposable & AsyncDisposable;
}