File: discriminatedUnionInference.types

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=== tests/cases/conformance/types/typeRelationships/typeInference/discriminatedUnionInference.ts ===
// Repro from #28862

type Foo<A> = { type: "foo", (): A[] };
>Foo : Foo<A>
>type : "foo"

type Bar<A> = { type: "bar", (): A };
>Bar : Bar<A>
>type : "bar"

type FooBar<A> = Foo<A> | Bar<A>;
>FooBar : FooBar<A>

type InferA<T> = T extends FooBar<infer A> ? A : never;
>InferA : InferA<T>

type FooA = InferA<Foo<number>>;  // number
>FooA : number

// Repro from #28862

type Item<T> = { kind: 'a', data: T } | { kind: 'b', data: T[] };
>Item : Item<T>
>kind : "a"
>data : T
>kind : "b"
>data : T[]

declare function foo<T>(item: Item<T>): T;
>foo : <T>(item: Item<T>) => T
>item : Item<T>

let x1 = foo({ kind: 'a', data: 42 });  // number
>x1 : number
>foo({ kind: 'a', data: 42 }) : number
>foo : <T>(item: Item<T>) => T
>{ kind: 'a', data: 42 } : { kind: "a"; data: number; }
>kind : "a"
>'a' : "a"
>data : number
>42 : 42

let x2 = foo({ kind: 'b', data: [1, 2] });  // number
>x2 : number
>foo({ kind: 'b', data: [1, 2] }) : number
>foo : <T>(item: Item<T>) => T
>{ kind: 'b', data: [1, 2] } : { kind: "b"; data: number[]; }
>kind : "b"
>'b' : "b"
>data : number[]
>[1, 2] : number[]
>1 : 1
>2 : 2