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=== tests/cases/compiler/keyofIsLiteralContexualType.ts ===
// keyof T is a literal contextual type
function foo<T extends { a: string, b: string }>() {
>foo : <T extends { a: string; b: string; }>() => void
>a : string
>b : string
let a: (keyof T)[] = ["a", "b"];
>a : (keyof T)[]
>["a", "b"] : ("a" | "b")[]
>"a" : "a"
>"b" : "b"
let b: (keyof T)[] = ["a", "b", "c"];
>b : (keyof T)[]
>["a", "b", "c"] : ("a" | "b" | "c")[]
>"a" : "a"
>"b" : "b"
>"c" : "c"
}
// Repro from #12455
declare function pick<T, K extends keyof T>(obj: T, propNames: K[]): Pick<T, K>;
>pick : <T, K extends keyof T>(obj: T, propNames: K[]) => Pick<T, K>
>obj : T
>propNames : K[]
let x = pick({ a: 10, b: 20, c: 30 }, ["a", "c"]);
>x : Pick<{ a: number; b: number; c: number; }, "a" | "c">
>pick({ a: 10, b: 20, c: 30 }, ["a", "c"]) : Pick<{ a: number; b: number; c: number; }, "a" | "c">
>pick : <T, K extends keyof T>(obj: T, propNames: K[]) => Pick<T, K>
>{ a: 10, b: 20, c: 30 } : { a: number; b: number; c: number; }
>a : number
>10 : 10
>b : number
>20 : 20
>c : number
>30 : 30
>["a", "c"] : ("a" | "c")[]
>"a" : "a"
>"c" : "c"
let b = x.b; // Error
>b : any
>x.b : any
>x : Pick<{ a: number; b: number; c: number; }, "a" | "c">
>b : any
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