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//// [keyRemappingKeyofResult.ts]
const sym = Symbol("")
type Orig = { [k: string]: any, str: any, [sym]: any }
type Okay = Exclude<keyof Orig, never>
// type Okay = string | number | typeof sym
type Remapped = { [K in keyof Orig as {} extends Record<K, any> ? never : K]: any }
/* type Remapped = {
str: any;
[sym]: any;
} */
// no string index signature, right?
type Oops = Exclude<keyof Remapped, never>
declare let x: Oops;
x = sym;
x = "str";
// type Oops = typeof sym <-- what happened to "str"?
// equivalently, with an unresolved generic (no `exclude` shenanigans, since conditions won't execute):
function f<T>() {
type Orig = { [k: string]: any, str: any, [sym]: any } & T;
type Okay = keyof Orig;
let a: Okay;
a = "str";
a = sym;
a = "whatever";
// type Okay = string | number | typeof sym
type Remapped = { [K in keyof Orig as {} extends Record<K, any> ? never : K]: any }
/* type Remapped = {
str: any;
[sym]: any;
} */
// no string index signature, right?
type Oops = keyof Remapped;
let x: Oops;
x = sym;
x = "str";
}
// and another generic case with a _distributive_ mapping, to trigger a different branch in `getIndexType`
function g<T>() {
type Orig = { [k: string]: any, str: any, [sym]: any } & T;
type Okay = keyof Orig;
let a: Okay;
a = "str";
a = sym;
a = "whatever";
// type Okay = string | number | typeof sym
type NonIndex<T extends PropertyKey> = {} extends Record<T, any> ? never : T;
type DistributiveNonIndex<T extends PropertyKey> = T extends unknown ? NonIndex<T> : never;
type Remapped = { [K in keyof Orig as DistributiveNonIndex<K>]: any }
/* type Remapped = {
str: any;
[sym]: any;
} */
// no string index signature, right?
type Oops = keyof Remapped;
let x: Oops;
x = sym;
x = "str";
}
export {};
//// [keyRemappingKeyofResult.js]
const sym = Symbol("");
x = sym;
x = "str";
// type Oops = typeof sym <-- what happened to "str"?
// equivalently, with an unresolved generic (no `exclude` shenanigans, since conditions won't execute):
function f() {
let a;
a = "str";
a = sym;
a = "whatever";
let x;
x = sym;
x = "str";
}
// and another generic case with a _distributive_ mapping, to trigger a different branch in `getIndexType`
function g() {
let a;
a = "str";
a = sym;
a = "whatever";
let x;
x = sym;
x = "str";
}
export {};
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