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=== tests/cases/compiler/keyRemappingKeyofResult.ts ===
const sym = Symbol("")
>sym : unique symbol
>Symbol("") : unique symbol
>Symbol : SymbolConstructor
>"" : ""
type Orig = { [k: string]: any, str: any, [sym]: any }
>Orig : { [k: string]: any; str: any; [sym]: any; }
>k : string
>str : any
>[sym] : any
>sym : unique symbol
type Okay = Exclude<keyof Orig, never>
>Okay : string | number | unique symbol
// type Okay = string | number | typeof sym
type Remapped = { [K in keyof Orig as {} extends Record<K, any> ? never : K]: any }
>Remapped : { str: any; [sym]: any; }
/* type Remapped = {
str: any;
[sym]: any;
} */
// no string index signature, right?
type Oops = Exclude<keyof Remapped, never>
>Oops : unique symbol | "str"
declare let x: Oops;
>x : Oops
x = sym;
>x = sym : unique symbol
>x : Oops
>sym : unique symbol
x = "str";
>x = "str" : "str"
>x : Oops
>"str" : "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>() {
>f : <T>() => void
type Orig = { [k: string]: any, str: any, [sym]: any } & T;
>Orig : { [k: string]: any; str: any; [sym]: any; } & T
>k : string
>str : any
>[sym] : any
>sym : unique symbol
type Okay = keyof Orig;
>Okay : string | number | unique symbol | keyof T
let a: Okay;
>a : string | number | unique symbol | keyof T
a = "str";
>a = "str" : "str"
>a : string | number | unique symbol | keyof T
>"str" : "str"
a = sym;
>a = sym : unique symbol
>a : string | number | unique symbol | keyof T
>sym : unique symbol
a = "whatever";
>a = "whatever" : "whatever"
>a : string | number | unique symbol | keyof T
>"whatever" : "whatever"
// type Okay = string | number | typeof sym
type Remapped = { [K in keyof Orig as {} extends Record<K, any> ? never : K]: any }
>Remapped : { [K in keyof ({ [k: string]: any; str: any; [sym]: any; } & T) as {} extends Record<K, any> ? never : K]: any; }
/* type Remapped = {
str: any;
[sym]: any;
} */
// no string index signature, right?
type Oops = keyof Remapped;
>Oops : keyof { [K in keyof ({ [k: string]: any; str: any; [sym]: any; } & T) as {} extends Record<K, any> ? never : K]: any; }
let x: Oops;
>x : keyof { [K in keyof ({ [k: string]: any; str: any; [sym]: any; } & T) as {} extends Record<K, any> ? never : K]: any; }
x = sym;
>x = sym : unique symbol
>x : keyof { [K in keyof ({ [k: string]: any; str: any; [sym]: any; } & T) as {} extends Record<K, any> ? never : K]: any; }
>sym : unique symbol
x = "str";
>x = "str" : "str"
>x : keyof { [K in keyof ({ [k: string]: any; str: any; [sym]: any; } & T) as {} extends Record<K, any> ? never : K]: any; }
>"str" : "str"
}
// and another generic case with a _distributive_ mapping, to trigger a different branch in `getIndexType`
function g<T>() {
>g : <T>() => void
type Orig = { [k: string]: any, str: any, [sym]: any } & T;
>Orig : { [k: string]: any; str: any; [sym]: any; } & T
>k : string
>str : any
>[sym] : any
>sym : unique symbol
type Okay = keyof Orig;
>Okay : string | number | unique symbol | keyof T
let a: Okay;
>a : string | number | unique symbol | keyof T
a = "str";
>a = "str" : "str"
>a : string | number | unique symbol | keyof T
>"str" : "str"
a = sym;
>a = sym : unique symbol
>a : string | number | unique symbol | keyof T
>sym : unique symbol
a = "whatever";
>a = "whatever" : "whatever"
>a : string | number | unique symbol | keyof T
>"whatever" : "whatever"
// type Okay = string | number | typeof sym
type NonIndex<T extends PropertyKey> = {} extends Record<T, any> ? never : T;
>NonIndex : {} extends Record<T, any> ? never : T
type DistributiveNonIndex<T extends PropertyKey> = T extends unknown ? NonIndex<T> : never;
>DistributiveNonIndex : T extends unknown ? {} extends Record<T, any> ? never : T : never
type Remapped = { [K in keyof Orig as DistributiveNonIndex<K>]: any }
>Remapped : { [K in keyof ({ [k: string]: any; str: any; [sym]: any; } & T) as K extends unknown ? {} extends Record<K, any> ? never : K : never]: any; }
/* type Remapped = {
str: any;
[sym]: any;
} */
// no string index signature, right?
type Oops = keyof Remapped;
>Oops : keyof { [K in keyof ({ [k: string]: any; str: any; [sym]: any; } & T) as K extends unknown ? {} extends Record<K, any> ? never : K : never]: any; }
let x: Oops;
>x : keyof { [K in keyof ({ [k: string]: any; str: any; [sym]: any; } & T) as K extends unknown ? {} extends Record<K, any> ? never : K : never]: any; }
x = sym;
>x = sym : unique symbol
>x : keyof { [K in keyof ({ [k: string]: any; str: any; [sym]: any; } & T) as K extends unknown ? {} extends Record<K, any> ? never : K : never]: any; }
>sym : unique symbol
x = "str";
>x = "str" : "str"
>x : keyof { [K in keyof ({ [k: string]: any; str: any; [sym]: any; } & T) as K extends unknown ? {} extends Record<K, any> ? never : K : never]: any; }
>"str" : "str"
}
export {};
|
