=== tests/cases/compiler/awaitUnionPromise.ts ===
// https://github.com/Microsoft/TypeScript/issues/18186

class AsyncEnumeratorDone { };
>AsyncEnumeratorDone : AsyncEnumeratorDone

interface IAsyncEnumerator<T> {
    next1(): Promise<T | AsyncEnumeratorDone>;
>next1 : () => Promise<T | AsyncEnumeratorDone>

    next2(): Promise<T> | Promise<AsyncEnumeratorDone>;
>next2 : () => Promise<T> | Promise<AsyncEnumeratorDone>

    next3(): Promise<T | {}>;
>next3 : () => Promise<T | {}>

    next4(): Promise<T | { x: string }>;
>next4 : () => Promise<T | {    x: string;}>
>x : string
}

async function main() {
>main : () => Promise<void>

    const x: IAsyncEnumerator<number> = null;
>x : IAsyncEnumerator<number>
>null : null

    let a = await x.next1();
>a : number | AsyncEnumeratorDone
>await x.next1() : number | AsyncEnumeratorDone
>x.next1() : Promise<number | AsyncEnumeratorDone>
>x.next1 : () => Promise<number | AsyncEnumeratorDone>
>x : IAsyncEnumerator<number>
>next1 : () => Promise<number | AsyncEnumeratorDone>

    let b = await x.next2();
>b : number | AsyncEnumeratorDone
>await x.next2() : number | AsyncEnumeratorDone
>x.next2() : Promise<AsyncEnumeratorDone> | Promise<number>
>x.next2 : () => Promise<AsyncEnumeratorDone> | Promise<number>
>x : IAsyncEnumerator<number>
>next2 : () => Promise<AsyncEnumeratorDone> | Promise<number>

    let c = await x.next3();
>c : number | {}
>await x.next3() : number | {}
>x.next3() : Promise<number | {}>
>x.next3 : () => Promise<number | {}>
>x : IAsyncEnumerator<number>
>next3 : () => Promise<number | {}>

    let d = await x.next4();
>d : number | { x: string; }
>await x.next4() : number | { x: string; }
>x.next4() : Promise<number | { x: string; }>
>x.next4 : () => Promise<number | { x: string; }>
>x : IAsyncEnumerator<number>
>next4 : () => Promise<number | { x: string; }>
}