Feature request: flowAsync #1658

const fetchUser = async (id: number) => db.users.find(id);
const getName = (user: User) => user.name;

const getUserName = flow(fetchUser, getName);
await getUserName(1); // TypeError: Cannot read property 'name' of [object Promise]

// current flow implementation
for (let i = 1; i < funcs.length; i++) {
  result = funcs[i].call(this, result); // passes raw Promise
}

const getUserName = flowAsync(fetchUser, getName);
await getUserName(1); // "Alice"

export function flowAsync(...funcs) {
  return async function (this: any, ...args: any[]) {
    let result = funcs.length ? await funcs[0].apply(this, args) : args[0];

    for (let i = 1; i < funcs.length; i++) {
      result = await funcs[i].call(this, result);
    }

    return result;
  };
}