await object

awaitObject.ts

type Await<T> = T extends Promise<infer V> ? Await<V> : T

type AwaitObject<Promises extends Record<string, Promise<unknown>>> = {
  [K in keyof Promises]: Await<Promises[K]>
}

async function awaitObject<Promises extends Record<string, Promise<unknown>>>(
  promises: Promises,
) {
  const pairs = await Promise.all(
    Object.entries(promises).map(
      async ([key, promise]) => [key, await promise] as const,
    ),
  )
  return Object.fromEntries(pairs) as AwaitObject<Promises>
}

const result = await awaitObject({
  a: Promise.resolve("test"),
  b: Promise.resolve(123),
})