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=== tests/cases/compiler/extractInferenceImprovement.ts ===
// repro mostly from https://github.com/Microsoft/TypeScript/issues/25065
function getProperty2<T, K extends keyof T>(obj: T, key: Extract<K, string>): T[K] {
>getProperty2 : Symbol(getProperty2, Decl(extractInferenceImprovement.ts, 0, 0))
>T : Symbol(T, Decl(extractInferenceImprovement.ts, 1, 22))
>K : Symbol(K, Decl(extractInferenceImprovement.ts, 1, 24))
>T : Symbol(T, Decl(extractInferenceImprovement.ts, 1, 22))
>obj : Symbol(obj, Decl(extractInferenceImprovement.ts, 1, 44))
>T : Symbol(T, Decl(extractInferenceImprovement.ts, 1, 22))
>key : Symbol(key, Decl(extractInferenceImprovement.ts, 1, 51))
>Extract : Symbol(Extract, Decl(lib.es5.d.ts, --, --))
>K : Symbol(K, Decl(extractInferenceImprovement.ts, 1, 24))
>T : Symbol(T, Decl(extractInferenceImprovement.ts, 1, 22))
>K : Symbol(K, Decl(extractInferenceImprovement.ts, 1, 24))
return obj[key];
>obj : Symbol(obj, Decl(extractInferenceImprovement.ts, 1, 44))
>key : Symbol(key, Decl(extractInferenceImprovement.ts, 1, 51))
}
function getProperty3<T, K extends Extract<keyof T, string>>(obj: T, key: K): T[K] {
>getProperty3 : Symbol(getProperty3, Decl(extractInferenceImprovement.ts, 3, 1))
>T : Symbol(T, Decl(extractInferenceImprovement.ts, 5, 22))
>K : Symbol(K, Decl(extractInferenceImprovement.ts, 5, 24))
>Extract : Symbol(Extract, Decl(lib.es5.d.ts, --, --))
>T : Symbol(T, Decl(extractInferenceImprovement.ts, 5, 22))
>obj : Symbol(obj, Decl(extractInferenceImprovement.ts, 5, 61))
>T : Symbol(T, Decl(extractInferenceImprovement.ts, 5, 22))
>key : Symbol(key, Decl(extractInferenceImprovement.ts, 5, 68))
>K : Symbol(K, Decl(extractInferenceImprovement.ts, 5, 24))
>T : Symbol(T, Decl(extractInferenceImprovement.ts, 5, 22))
>K : Symbol(K, Decl(extractInferenceImprovement.ts, 5, 24))
return obj[key];
>obj : Symbol(obj, Decl(extractInferenceImprovement.ts, 5, 61))
>key : Symbol(key, Decl(extractInferenceImprovement.ts, 5, 68))
}
const s = Symbol();
>s : Symbol(s, Decl(extractInferenceImprovement.ts, 9, 5))
>Symbol : Symbol(Symbol, Decl(lib.es5.d.ts, --, --), Decl(lib.es2015.symbol.d.ts, --, --), Decl(lib.es2015.symbol.wellknown.d.ts, --, --))
interface StrNum {
>StrNum : Symbol(StrNum, Decl(extractInferenceImprovement.ts, 9, 19))
first: string;
>first : Symbol(StrNum.first, Decl(extractInferenceImprovement.ts, 10, 18))
second: number;
>second : Symbol(StrNum.second, Decl(extractInferenceImprovement.ts, 11, 18))
[s]: string;
>[s] : Symbol(StrNum[s], Decl(extractInferenceImprovement.ts, 12, 19))
>s : Symbol(s, Decl(extractInferenceImprovement.ts, 9, 5))
}
const obj: StrNum = {} as any;
>obj : Symbol(obj, Decl(extractInferenceImprovement.ts, 15, 5))
>StrNum : Symbol(StrNum, Decl(extractInferenceImprovement.ts, 9, 19))
let prop: string;
>prop : Symbol(prop, Decl(extractInferenceImprovement.ts, 17, 3))
// should work
prop = getProperty2(obj, 'first');
>prop : Symbol(prop, Decl(extractInferenceImprovement.ts, 17, 3))
>getProperty2 : Symbol(getProperty2, Decl(extractInferenceImprovement.ts, 0, 0))
>obj : Symbol(obj, Decl(extractInferenceImprovement.ts, 15, 5))
prop = getProperty3(obj, 'first');
>prop : Symbol(prop, Decl(extractInferenceImprovement.ts, 17, 3))
>getProperty3 : Symbol(getProperty3, Decl(extractInferenceImprovement.ts, 3, 1))
>obj : Symbol(obj, Decl(extractInferenceImprovement.ts, 15, 5))
// Should fail
prop = getProperty2(obj, s);
>prop : Symbol(prop, Decl(extractInferenceImprovement.ts, 17, 3))
>getProperty2 : Symbol(getProperty2, Decl(extractInferenceImprovement.ts, 0, 0))
>obj : Symbol(obj, Decl(extractInferenceImprovement.ts, 15, 5))
>s : Symbol(s, Decl(extractInferenceImprovement.ts, 9, 5))
prop = getProperty3(obj, s);
>prop : Symbol(prop, Decl(extractInferenceImprovement.ts, 17, 3))
>getProperty3 : Symbol(getProperty3, Decl(extractInferenceImprovement.ts, 3, 1))
>obj : Symbol(obj, Decl(extractInferenceImprovement.ts, 15, 5))
>s : Symbol(s, Decl(extractInferenceImprovement.ts, 9, 5))
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