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x/jotai/src/utils/waitForAll.ts

👻 Primitive and flexible state management for React
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import { atom } from 'jotai'import type { Atom } from 'jotai'import { createMemoizeAtom } from './weakCache'
const memoizeAtom = createMemoizeAtom()
type Awaited<T> = T extends Promise<infer V> ? Awaited<V> : Ttype ResolveAtom<T> = T extends Atom<infer V> ? V : Ttype AwaitedAtom<T> = Awaited<ResolveAtom<T>>
export function waitForAll<Atoms extends Atom<unknown>[]>( atoms: readonly [...Atoms]): Atom<{ [K in keyof Atoms]: AwaitedAtom<Atoms[K]>}>
export function waitForAll<Atoms extends Record<string, Atom<unknown>>>( atoms: Atoms): Atom<{ [K in keyof Atoms]: AwaitedAtom<Atoms[K]>}>
export function waitForAll< Atoms extends Record<string, Atom<unknown>> | readonly Atom<unknown>[]>(atoms: Atoms) { const createAtom = () => { const unwrappedAtoms = unwrapAtoms(atoms) const derivedAtom = atom((get) => { const promises: Promise<unknown>[] = [] const values = unwrappedAtoms.map((anAtom, index) => { try { return get(anAtom) } catch (e) { if (e instanceof Promise) { promises[index] = e } else { throw e } } }) if (promises.length) { throw Promise.all(promises) } return wrapResults(atoms, values) as { [K in keyof Atoms]: AwaitedAtom<Atoms[K]> } }) return derivedAtom }
if (Array.isArray(atoms)) { return memoizeAtom(createAtom, atoms) } return createAtom()}
const unwrapAtoms = < Atoms extends Record<string, Atom<unknown>> | readonly Atom<unknown>[]>( atoms: Atoms): Atom<unknown>[] => Array.isArray(atoms) ? atoms : Object.getOwnPropertyNames(atoms).map((key) => atoms[key as keyof Atoms])
const wrapResults = < Atoms extends Record<string, Atom<unknown>> | readonly Atom<unknown>[]>( atoms: Atoms, results: unknown[]): unknown[] | Record<string, unknown> => Array.isArray(atoms) ? results : Object.getOwnPropertyNames(atoms).reduce( (out, key, idx) => ({ ...out, [key]: results[idx] }), {} )