1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
|
=== tests/cases/compiler/inferConditionalConstraintMappedMember.ts ===
// Return keyof type without string index signature
type KeysWithoutStringIndex<T> =
>KeysWithoutStringIndex : Symbol(KeysWithoutStringIndex, Decl(inferConditionalConstraintMappedMember.ts, 0, 0))
>T : Symbol(T, Decl(inferConditionalConstraintMappedMember.ts, 1, 28))
{ [K in keyof T]: string extends K ? never : K } extends { [_ in keyof T]: infer U }
>K : Symbol(K, Decl(inferConditionalConstraintMappedMember.ts, 2, 7))
>T : Symbol(T, Decl(inferConditionalConstraintMappedMember.ts, 1, 28))
>K : Symbol(K, Decl(inferConditionalConstraintMappedMember.ts, 2, 7))
>K : Symbol(K, Decl(inferConditionalConstraintMappedMember.ts, 2, 7))
>_ : Symbol(_, Decl(inferConditionalConstraintMappedMember.ts, 2, 64))
>T : Symbol(T, Decl(inferConditionalConstraintMappedMember.ts, 1, 28))
>U : Symbol(U, Decl(inferConditionalConstraintMappedMember.ts, 2, 84))
? U
>U : Symbol(U, Decl(inferConditionalConstraintMappedMember.ts, 2, 84))
: never
// Only "foo" | "bar" as expected, [string] index signature removed
type test = KeysWithoutStringIndex<{ [index: string]: string; foo: string; bar: 'baz' }>
>test : Symbol(test, Decl(inferConditionalConstraintMappedMember.ts, 4, 11))
>KeysWithoutStringIndex : Symbol(KeysWithoutStringIndex, Decl(inferConditionalConstraintMappedMember.ts, 0, 0))
>index : Symbol(index, Decl(inferConditionalConstraintMappedMember.ts, 7, 38))
>foo : Symbol(foo, Decl(inferConditionalConstraintMappedMember.ts, 7, 61))
>bar : Symbol(bar, Decl(inferConditionalConstraintMappedMember.ts, 7, 74))
// KeysWithoutStringIndex<T> will always be a subset of keyof T, but is reported as unassignable
export type RemoveIdxSgn<T> = Pick<T, KeysWithoutStringIndex<T>>
>RemoveIdxSgn : Symbol(RemoveIdxSgn, Decl(inferConditionalConstraintMappedMember.ts, 7, 88))
>T : Symbol(T, Decl(inferConditionalConstraintMappedMember.ts, 9, 25))
>Pick : Symbol(Pick, Decl(lib.es5.d.ts, --, --))
>T : Symbol(T, Decl(inferConditionalConstraintMappedMember.ts, 9, 25))
>KeysWithoutStringIndex : Symbol(KeysWithoutStringIndex, Decl(inferConditionalConstraintMappedMember.ts, 0, 0))
>T : Symbol(T, Decl(inferConditionalConstraintMappedMember.ts, 9, 25))
// ERROR:
// Type 'KeysWithoutStringIndex<T>' does not satisfy the constraint 'keyof T'.
// Type 'unknown' is not assignable to type 'keyof T'.(2344)
|
