File: inferConditionalConstraintMappedMember.types

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=== tests/cases/compiler/inferConditionalConstraintMappedMember.ts ===
// Return keyof type without string index signature
type KeysWithoutStringIndex<T> =
>KeysWithoutStringIndex : KeysWithoutStringIndex<T>

    { [K in keyof T]: string extends K ? never : K } extends { [_ in keyof T]: infer U }
    ? U
    : never

// Only "foo" | "bar" as expected, [string] index signature removed
type test = KeysWithoutStringIndex<{ [index: string]: string; foo: string; bar: 'baz' }>
>test : never
>index : string
>foo : string
>bar : "baz"

// KeysWithoutStringIndex<T> will always be a subset of keyof T, but is reported as unassignable
export type RemoveIdxSgn<T> = Pick<T, KeysWithoutStringIndex<T>>
>RemoveIdxSgn : RemoveIdxSgn<T>

  // ERROR:
  // Type 'KeysWithoutStringIndex<T>' does not satisfy the constraint 'keyof T'.
  //  Type 'unknown' is not assignable to type 'keyof T'.(2344)