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=== tests/cases/compiler/unionOfClassCalls.ts ===
// from https://github.com/microsoft/TypeScript/issues/30717
declare class Test<T> {
>Test : Test<T>
obj: T;
>obj : T
get<K extends keyof T>(k: K): T[K];
>get : <K extends keyof T>(k: K) => T[K]
>k : K
}
interface A { t: "A" }
>t : "A"
interface B { t: "B" }
>t : "B"
declare const tmp: Test<A> | Test<B>;
>tmp : Test<A> | Test<B>
switch (tmp.get('t')) {
>tmp.get('t') : "A" | "B"
>tmp.get : (<K extends "t">(k: K) => A[K]) | (<K extends "t">(k: K) => B[K])
>tmp : Test<A> | Test<B>
>get : (<K extends "t">(k: K) => A[K]) | (<K extends "t">(k: K) => B[K])
>'t' : "t"
case 'A': break;
>'A' : "A"
case 'B': break;
>'B' : "B"
}
// from https://github.com/microsoft/TypeScript/issues/36390
const arr: number[] | string[] = []; // Works with Array<number | string>
>arr : number[] | string[]
>[] : never[]
const arr1: number[] = [];
>arr1 : number[]
>[] : never[]
const arr2: string[] = [];
>arr2 : string[]
>[] : never[]
arr.map((a: number | string, index: number) => {
>arr.map((a: number | string, index: number) => { return index}) : number[]
>arr.map : (<U>(callbackfn: (value: number, index: number, array: number[]) => U, thisArg?: any) => U[]) | (<U>(callbackfn: (value: string, index: number, array: string[]) => U, thisArg?: any) => U[])
>arr : number[] | string[]
>map : (<U>(callbackfn: (value: number, index: number, array: number[]) => U, thisArg?: any) => U[]) | (<U>(callbackfn: (value: string, index: number, array: string[]) => U, thisArg?: any) => U[])
>(a: number | string, index: number) => { return index} : (a: number | string, index: number) => number
>a : string | number
>index : number
return index
>index : number
})
// This case still doesn't work because `reduce` has multiple overloads :(
arr.reduce((acc: Array<string>, a: number | string, index: number) => {
>arr.reduce((acc: Array<string>, a: number | string, index: number) => { return []}, []) : any
>arr.reduce : { (callbackfn: (previousValue: number, currentValue: number, currentIndex: number, array: number[]) => number): number; (callbackfn: (previousValue: number, currentValue: number, currentIndex: number, array: number[]) => number, initialValue: number): number; <U>(callbackfn: (previousValue: U, currentValue: number, currentIndex: number, array: number[]) => U, initialValue: U): U; } | { (callbackfn: (previousValue: string, currentValue: string, currentIndex: number, array: string[]) => string): string; (callbackfn: (previousValue: string, currentValue: string, currentIndex: number, array: string[]) => string, initialValue: string): string; <U>(callbackfn: (previousValue: U, currentValue: string, currentIndex: number, array: string[]) => U, initialValue: U): U; }
>arr : number[] | string[]
>reduce : { (callbackfn: (previousValue: number, currentValue: number, currentIndex: number, array: number[]) => number): number; (callbackfn: (previousValue: number, currentValue: number, currentIndex: number, array: number[]) => number, initialValue: number): number; <U>(callbackfn: (previousValue: U, currentValue: number, currentIndex: number, array: number[]) => U, initialValue: U): U; } | { (callbackfn: (previousValue: string, currentValue: string, currentIndex: number, array: string[]) => string): string; (callbackfn: (previousValue: string, currentValue: string, currentIndex: number, array: string[]) => string, initialValue: string): string; <U>(callbackfn: (previousValue: U, currentValue: string, currentIndex: number, array: string[]) => U, initialValue: U): U; }
>(acc: Array<string>, a: number | string, index: number) => { return []} : (acc: Array<string>, a: number | string, index: number) => never[]
>acc : string[]
>a : string | number
>index : number
return []
>[] : never[]
}, [])
>[] : never[]
arr.forEach((a: number | string, index: number) => {
>arr.forEach((a: number | string, index: number) => { return index}) : void
>arr.forEach : ((callbackfn: (value: number, index: number, array: number[]) => void, thisArg?: any) => void) | ((callbackfn: (value: string, index: number, array: string[]) => void, thisArg?: any) => void)
>arr : number[] | string[]
>forEach : ((callbackfn: (value: number, index: number, array: number[]) => void, thisArg?: any) => void) | ((callbackfn: (value: string, index: number, array: string[]) => void, thisArg?: any) => void)
>(a: number | string, index: number) => { return index} : (a: number | string, index: number) => number
>a : string | number
>index : number
return index
>index : number
})
arr1.map((a: number, index: number) => {
>arr1.map((a: number, index: number) => { return index}) : number[]
>arr1.map : <U>(callbackfn: (value: number, index: number, array: number[]) => U, thisArg?: any) => U[]
>arr1 : number[]
>map : <U>(callbackfn: (value: number, index: number, array: number[]) => U, thisArg?: any) => U[]
>(a: number, index: number) => { return index} : (a: number, index: number) => number
>a : number
>index : number
return index
>index : number
})
arr1.reduce((acc: number[], a: number, index: number) => {
>arr1.reduce((acc: number[], a: number, index: number) => { return [a]}, []) : number[]
>arr1.reduce : { (callbackfn: (previousValue: number, currentValue: number, currentIndex: number, array: number[]) => number): number; (callbackfn: (previousValue: number, currentValue: number, currentIndex: number, array: number[]) => number, initialValue: number): number; <U>(callbackfn: (previousValue: U, currentValue: number, currentIndex: number, array: number[]) => U, initialValue: U): U; }
>arr1 : number[]
>reduce : { (callbackfn: (previousValue: number, currentValue: number, currentIndex: number, array: number[]) => number): number; (callbackfn: (previousValue: number, currentValue: number, currentIndex: number, array: number[]) => number, initialValue: number): number; <U>(callbackfn: (previousValue: U, currentValue: number, currentIndex: number, array: number[]) => U, initialValue: U): U; }
>(acc: number[], a: number, index: number) => { return [a]} : (acc: number[], a: number, index: number) => number[]
>acc : number[]
>a : number
>index : number
return [a]
>[a] : number[]
>a : number
}, [])
>[] : never[]
arr1.forEach((a: number, index: number) => {
>arr1.forEach((a: number, index: number) => { return index}) : void
>arr1.forEach : (callbackfn: (value: number, index: number, array: number[]) => void, thisArg?: any) => void
>arr1 : number[]
>forEach : (callbackfn: (value: number, index: number, array: number[]) => void, thisArg?: any) => void
>(a: number, index: number) => { return index} : (a: number, index: number) => number
>a : number
>index : number
return index
>index : number
})
arr2.map((a: string, index: number) => {
>arr2.map((a: string, index: number) => { return index}) : number[]
>arr2.map : <U>(callbackfn: (value: string, index: number, array: string[]) => U, thisArg?: any) => U[]
>arr2 : string[]
>map : <U>(callbackfn: (value: string, index: number, array: string[]) => U, thisArg?: any) => U[]
>(a: string, index: number) => { return index} : (a: string, index: number) => number
>a : string
>index : number
return index
>index : number
})
arr2.reduce((acc: string[], a: string, index: number) => {
>arr2.reduce((acc: string[], a: string, index: number) => { return []}, []) : never[]
>arr2.reduce : { (callbackfn: (previousValue: string, currentValue: string, currentIndex: number, array: string[]) => string): string; (callbackfn: (previousValue: string, currentValue: string, currentIndex: number, array: string[]) => string, initialValue: string): string; <U>(callbackfn: (previousValue: U, currentValue: string, currentIndex: number, array: string[]) => U, initialValue: U): U; }
>arr2 : string[]
>reduce : { (callbackfn: (previousValue: string, currentValue: string, currentIndex: number, array: string[]) => string): string; (callbackfn: (previousValue: string, currentValue: string, currentIndex: number, array: string[]) => string, initialValue: string): string; <U>(callbackfn: (previousValue: U, currentValue: string, currentIndex: number, array: string[]) => U, initialValue: U): U; }
>(acc: string[], a: string, index: number) => { return []} : (acc: string[], a: string, index: number) => never[]
>acc : string[]
>a : string
>index : number
return []
>[] : never[]
}, [])
>[] : never[]
arr2.forEach((a: string, index: number) => {
>arr2.forEach((a: string, index: number) => { return index}) : void
>arr2.forEach : (callbackfn: (value: string, index: number, array: string[]) => void, thisArg?: any) => void
>arr2 : string[]
>forEach : (callbackfn: (value: string, index: number, array: string[]) => void, thisArg?: any) => void
>(a: string, index: number) => { return index} : (a: string, index: number) => number
>a : string
>index : number
return index
>index : number
})
// from https://github.com/microsoft/TypeScript/issues/36307
declare class Foo {
>Foo : Foo
doThing(): Promise<this>
>doThing : () => Promise<this>
}
declare class Bar extends Foo {
>Bar : Bar
>Foo : Foo
bar: number;
>bar : number
}
declare class Baz extends Foo {
>Baz : Baz
>Foo : Foo
baz: number;
>baz : number
}
declare var a: Bar | Baz;
>a : Bar | Baz
// note, you must annotate `result` for now
a.doThing().then((result: Bar | Baz) => {
>a.doThing().then((result: Bar | Baz) => { // whatever}) : Promise<void>
>a.doThing().then : (<TResult1 = Baz, TResult2 = never>(onfulfilled?: ((value: Baz) => TResult1 | PromiseLike<TResult1>) | null | undefined, onrejected?: ((reason: any) => TResult2 | PromiseLike<TResult2>) | null | undefined) => Promise<TResult1 | TResult2>) | (<TResult1 = Bar, TResult2 = never>(onfulfilled?: ((value: Bar) => TResult1 | PromiseLike<TResult1>) | null | undefined, onrejected?: ((reason: any) => TResult2 | PromiseLike<TResult2>) | null | undefined) => Promise<TResult1 | TResult2>)
>a.doThing() : Promise<Bar> | Promise<Baz>
>a.doThing : (() => Promise<Bar>) | (() => Promise<Baz>)
>a : Bar | Baz
>doThing : (() => Promise<Bar>) | (() => Promise<Baz>)
>then : (<TResult1 = Baz, TResult2 = never>(onfulfilled?: ((value: Baz) => TResult1 | PromiseLike<TResult1>) | null | undefined, onrejected?: ((reason: any) => TResult2 | PromiseLike<TResult2>) | null | undefined) => Promise<TResult1 | TResult2>) | (<TResult1 = Bar, TResult2 = never>(onfulfilled?: ((value: Bar) => TResult1 | PromiseLike<TResult1>) | null | undefined, onrejected?: ((reason: any) => TResult2 | PromiseLike<TResult2>) | null | undefined) => Promise<TResult1 | TResult2>)
>(result: Bar | Baz) => { // whatever} : (result: Bar | Baz) => void
>result : Bar | Baz
// whatever
});
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