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=== tests/cases/compiler/inferenceShouldFailOnEvolvingArrays.ts ===
// repro from https://github.com/Microsoft/TypeScript/issues/25675
// The type of `arg` blocks inference but simplifies to T.
function logLength<T extends string, U extends string>(arg: { [K in U]: T }[U]): T {
>logLength : Symbol(logLength, Decl(inferenceShouldFailOnEvolvingArrays.ts, 0, 0))
>T : Symbol(T, Decl(inferenceShouldFailOnEvolvingArrays.ts, 2, 19))
>U : Symbol(U, Decl(inferenceShouldFailOnEvolvingArrays.ts, 2, 36))
>arg : Symbol(arg, Decl(inferenceShouldFailOnEvolvingArrays.ts, 2, 55))
>K : Symbol(K, Decl(inferenceShouldFailOnEvolvingArrays.ts, 2, 63))
>U : Symbol(U, Decl(inferenceShouldFailOnEvolvingArrays.ts, 2, 36))
>T : Symbol(T, Decl(inferenceShouldFailOnEvolvingArrays.ts, 2, 19))
>U : Symbol(U, Decl(inferenceShouldFailOnEvolvingArrays.ts, 2, 36))
>T : Symbol(T, Decl(inferenceShouldFailOnEvolvingArrays.ts, 2, 19))
console.log(arg.length);
>console.log : Symbol(Console.log, Decl(lib.dom.d.ts, --, --))
>console : Symbol(console, Decl(lib.dom.d.ts, --, --))
>log : Symbol(Console.log, Decl(lib.dom.d.ts, --, --))
>arg.length : Symbol(String.length, Decl(lib.es5.d.ts, --, --))
>arg : Symbol(arg, Decl(inferenceShouldFailOnEvolvingArrays.ts, 2, 55))
>length : Symbol(String.length, Decl(lib.es5.d.ts, --, --))
return arg;
>arg : Symbol(arg, Decl(inferenceShouldFailOnEvolvingArrays.ts, 2, 55))
}
logLength(42); // error
>logLength : Symbol(logLength, Decl(inferenceShouldFailOnEvolvingArrays.ts, 0, 0))
let z;
>z : Symbol(z, Decl(inferenceShouldFailOnEvolvingArrays.ts, 7, 3))
z = logLength(42); // no error; T is inferred as `any`
>z : Symbol(z, Decl(inferenceShouldFailOnEvolvingArrays.ts, 7, 3))
>logLength : Symbol(logLength, Decl(inferenceShouldFailOnEvolvingArrays.ts, 0, 0))
function logFirstLength<T extends string[], U extends string>(arg: { [K in U]: T }[U]): T {
>logFirstLength : Symbol(logFirstLength, Decl(inferenceShouldFailOnEvolvingArrays.ts, 8, 18))
>T : Symbol(T, Decl(inferenceShouldFailOnEvolvingArrays.ts, 10, 24))
>U : Symbol(U, Decl(inferenceShouldFailOnEvolvingArrays.ts, 10, 43))
>arg : Symbol(arg, Decl(inferenceShouldFailOnEvolvingArrays.ts, 10, 62))
>K : Symbol(K, Decl(inferenceShouldFailOnEvolvingArrays.ts, 10, 70))
>U : Symbol(U, Decl(inferenceShouldFailOnEvolvingArrays.ts, 10, 43))
>T : Symbol(T, Decl(inferenceShouldFailOnEvolvingArrays.ts, 10, 24))
>U : Symbol(U, Decl(inferenceShouldFailOnEvolvingArrays.ts, 10, 43))
>T : Symbol(T, Decl(inferenceShouldFailOnEvolvingArrays.ts, 10, 24))
console.log(arg[0].length);
>console.log : Symbol(Console.log, Decl(lib.dom.d.ts, --, --))
>console : Symbol(console, Decl(lib.dom.d.ts, --, --))
>log : Symbol(Console.log, Decl(lib.dom.d.ts, --, --))
>arg[0].length : Symbol(String.length, Decl(lib.es5.d.ts, --, --))
>arg : Symbol(arg, Decl(inferenceShouldFailOnEvolvingArrays.ts, 10, 62))
>length : Symbol(String.length, Decl(lib.es5.d.ts, --, --))
return arg;
>arg : Symbol(arg, Decl(inferenceShouldFailOnEvolvingArrays.ts, 10, 62))
}
logFirstLength([42]); // error
>logFirstLength : Symbol(logFirstLength, Decl(inferenceShouldFailOnEvolvingArrays.ts, 8, 18))
let zz = [];
>zz : Symbol(zz, Decl(inferenceShouldFailOnEvolvingArrays.ts, 15, 3))
zz.push(logLength(42)); // no error; T is inferred as `any`
>zz.push : Symbol(Array.push, Decl(lib.es5.d.ts, --, --))
>zz : Symbol(zz, Decl(inferenceShouldFailOnEvolvingArrays.ts, 15, 3))
>push : Symbol(Array.push, Decl(lib.es5.d.ts, --, --))
>logLength : Symbol(logLength, Decl(inferenceShouldFailOnEvolvingArrays.ts, 0, 0))
zz = logFirstLength([42]); // no error; T is inferred as `any[]`
>zz : Symbol(zz, Decl(inferenceShouldFailOnEvolvingArrays.ts, 15, 3))
>logFirstLength : Symbol(logFirstLength, Decl(inferenceShouldFailOnEvolvingArrays.ts, 8, 18))
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