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//// [awaitedType.ts]
type T1 = Awaited<number>;
type T2 = Awaited<Promise<number>>;
type T3 = Awaited<number | Promise<number>>;
type T4 = Awaited<number | Promise<string>>;
type T5 = Awaited<{ then: number }>;
type T6 = Awaited<{ then(): void }>; // never (non-promise "thenable")
type T7 = Awaited<{ then(x: number): void }>; // never (non-promise "thenable")
type T8 = Awaited<{ then(x: () => void): void }>; // unknown
type T9 = Awaited<any>;
type T10 = Awaited<never>;
type T11 = Awaited<unknown>;
type T12 = Awaited<Promise<Promise<number>>>;
type T13 = _Expect<Awaited<Promise<Promise<number>> | string | null>, /*expected*/ string | number | null>; // otherwise just prints T13 in types tests, which isn't very helpful
type T14 = _Expect<Awaited<Promise<Promise<number>> | string | undefined>, /*expected*/ string | number | undefined>; // otherwise just prints T14 in types tests, which isn't very helpful
type T15 = _Expect<Awaited<Promise<Promise<number>> | string | null | undefined>, /*expected*/ string | number | null | undefined>; // otherwise just prints T15 in types tests, which isn't very helpful
interface BadPromise { then(cb: (value: BadPromise) => void): void; }
type T16 = Awaited<BadPromise>; // error
interface BadPromise1 { then(cb: (value: BadPromise2) => void): void; }
interface BadPromise2 { then(cb: (value: BadPromise1) => void): void; }
type T17 = Awaited<BadPromise1>; // error
// https://github.com/microsoft/TypeScript/issues/46934
type T18 = Awaited<{ then(cb: (value: number, other: { }) => void)}>; // number
// https://github.com/microsoft/TypeScript/issues/33562
type MaybePromise<T> = T | Promise<T> | PromiseLike<T>
declare function MaybePromise<T>(value: T): MaybePromise<T>;
async function main() {
let aaa: number;
let bbb: string;
[
aaa,
bbb,
] = await Promise.all([
MaybePromise(1),
MaybePromise('2'),
MaybePromise(true),
])
}
// non-generic
async function f1(x: string) {
// y: string
const y = await x;
}
async function f2(x: unknown) {
// y: unknown
const y = await x;
}
async function f3(x: object) {
// y: object
const y = await x;
}
async function f4(x: Promise<string>) {
// y: string
const y = await x;
}
async function f5(x: Promise<unknown>) {
// y: unknown
const y = await x;
}
async function f6(x: Promise<object>) {
// y: object
const y = await x;
}
// generic
async function f7<T>(x: T) {
// NOTE: T does not belong solely to the domain of primitive types and either does
// not have a base constraint, its base constraint is `any`, `unknown`, `{}`, or `object`,
// or it has a non-primitive base constraint with a callable `then`.
// y: Awaited<T>
const y = await x;
}
async function f8<T extends any>(x: T) {
// NOTE: T does not belong solely to the domain of primitive types and either does
// not have a base constraint, its base constraint is `any`, `unknown`, `{}`, or `object`,
// or it has a non-primitive base constraint with a callable `then`.
// y: Awaited<T>
const y = await x;
}
async function f9<T extends unknown>(x: T) {
// NOTE: T does not belong solely to the domain of primitive types and either does
// not have a base constraint, its base constraint is `any`, `unknown`, `{}`, or `object`,
// or it has a non-primitive base constraint with a callable `then`.
// y: Awaited<T>
const y = await x;
}
async function f10<T extends {}>(x: T) {
// NOTE: T does not belong solely to the domain of primitive types and either does
// not have a base constraint, its base constraint is `any`, `unknown`, `{}`, or `object`,
// or it has a non-primitive base constraint with a callable `then`.
// y: Awaited<T>
const y = await x;
}
async function f11<T extends { then(onfulfilled: (value: unknown) => void): void }>(x: T) {
// NOTE: T does not belong solely to the domain of primitive types and either does
// not have a base constraint, its base constraint is `any`, `unknown`, `{}`, or `object`,
// or it has a non-primitive base constraint with a callable `then`.
// y: Awaited<T>
const y = await x;
}
async function f12<T extends string | object>(x: T) {
// NOTE: T does not belong solely to the domain of primitive types and either does
// not have a base constraint, its base constraint is `any`, `unknown`, `{}`, or `object`,
// or it has a non-primitive base constraint with a callable `then`.
// y: Awaited<T>
const y = await x;
}
async function f13<T extends string>(x: T) {
// NOTE: T belongs to the domain of primitive types
// y: T
const y = await x;
}
async function f14<T extends { x: number }>(x: T) {
// NOTE: T has a non-primitive base constraint without a callable `then`.
// y: T
const y = await x;
}
async function f15<T extends { then: number }>(x: T) {
// NOTE: T has a non-primitive base constraint without a callable `then`.
// y: T
const y = await x;
}
async function f16<T extends number & { then(): void }>(x: T) {
// NOTE: T belongs to the domain of primitive types (regardless of `then`)
// y: T
const y = await x;
}
// helps with tests where '.types' just prints out the type alias name
type _Expect<TActual extends TExpected, TExpected> = TActual;
// https://github.com/microsoft/TypeScript/issues/48320
async function f17<T extends (...args: any[]) => Promise<any>>(fn: T) {
const ret: Awaited<ReturnType<T>> = await fn(1, 2, 3);
return ret;
}
async function f17_usage() {
const x = await f17(async () => 123 as const);
return { x };
}
// https://github.com/microsoft/TypeScript/issues/47144
type GenericStructure<
AcceptableKeyType extends string = string
> = Record<AcceptableKeyType, number>;
async function brokenExample<AcceptableKeyType extends string = string>(structurePromise: Promise<GenericStructure<AcceptableKeyType>>, key: AcceptableKeyType): Promise<void> {
const structure = await structurePromise;
structure[key] = 1;
}
//// [awaitedType.js]
async function main() {
let aaa;
let bbb;
[
aaa,
bbb,
] = await Promise.all([
MaybePromise(1),
MaybePromise('2'),
MaybePromise(true),
]);
}
// non-generic
async function f1(x) {
// y: string
const y = await x;
}
async function f2(x) {
// y: unknown
const y = await x;
}
async function f3(x) {
// y: object
const y = await x;
}
async function f4(x) {
// y: string
const y = await x;
}
async function f5(x) {
// y: unknown
const y = await x;
}
async function f6(x) {
// y: object
const y = await x;
}
// generic
async function f7(x) {
// NOTE: T does not belong solely to the domain of primitive types and either does
// not have a base constraint, its base constraint is `any`, `unknown`, `{}`, or `object`,
// or it has a non-primitive base constraint with a callable `then`.
// y: Awaited<T>
const y = await x;
}
async function f8(x) {
// NOTE: T does not belong solely to the domain of primitive types and either does
// not have a base constraint, its base constraint is `any`, `unknown`, `{}`, or `object`,
// or it has a non-primitive base constraint with a callable `then`.
// y: Awaited<T>
const y = await x;
}
async function f9(x) {
// NOTE: T does not belong solely to the domain of primitive types and either does
// not have a base constraint, its base constraint is `any`, `unknown`, `{}`, or `object`,
// or it has a non-primitive base constraint with a callable `then`.
// y: Awaited<T>
const y = await x;
}
async function f10(x) {
// NOTE: T does not belong solely to the domain of primitive types and either does
// not have a base constraint, its base constraint is `any`, `unknown`, `{}`, or `object`,
// or it has a non-primitive base constraint with a callable `then`.
// y: Awaited<T>
const y = await x;
}
async function f11(x) {
// NOTE: T does not belong solely to the domain of primitive types and either does
// not have a base constraint, its base constraint is `any`, `unknown`, `{}`, or `object`,
// or it has a non-primitive base constraint with a callable `then`.
// y: Awaited<T>
const y = await x;
}
async function f12(x) {
// NOTE: T does not belong solely to the domain of primitive types and either does
// not have a base constraint, its base constraint is `any`, `unknown`, `{}`, or `object`,
// or it has a non-primitive base constraint with a callable `then`.
// y: Awaited<T>
const y = await x;
}
async function f13(x) {
// NOTE: T belongs to the domain of primitive types
// y: T
const y = await x;
}
async function f14(x) {
// NOTE: T has a non-primitive base constraint without a callable `then`.
// y: T
const y = await x;
}
async function f15(x) {
// NOTE: T has a non-primitive base constraint without a callable `then`.
// y: T
const y = await x;
}
async function f16(x) {
// NOTE: T belongs to the domain of primitive types (regardless of `then`)
// y: T
const y = await x;
}
// https://github.com/microsoft/TypeScript/issues/48320
async function f17(fn) {
const ret = await fn(1, 2, 3);
return ret;
}
async function f17_usage() {
const x = await f17(async () => 123);
return { x };
}
async function brokenExample(structurePromise, key) {
const structure = await structurePromise;
structure[key] = 1;
}
|
