TypeScript/tests/baselines/reference/mappedArrayTupleIntersections.types at eab5db9551fff7e7d4506f3ab68d6412a7d0ca07 · microsoft/TypeScript · GitHub

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//// [tests/cases/compiler/mappedArrayTupleIntersections.ts] ////

=== mappedArrayTupleIntersections.ts ===
type Box<T> = { value: T };
>Box : Box<T>
>    : ^^^^^^
>value : T
>      : ^

type Boxify<T> = { [K in keyof T]: Box<T[K]> };
>Boxify : Boxify<T>
>       : ^^^^^^^^^

type T1 = Boxify<string[]>;
>T1 : Box<string>[]
>   : ^^^^^^^^^^^^^

type T2 = Boxify<[string, string]>;
>T2 : [Box<string>, Box<string>]
>   : ^^^^^^^^^^^^^^^^^^^^^^^^^^

type T3 = Boxify<string[] & unknown[]>;
>T3 : Box<string>[] & Box<unknown>[]
>   : ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

type T4 = Boxify<string[] & [string, string]>;
>T4 : Box<string>[] & [Box<string>, Box<string>]
>   : ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

type T5 = Boxify<string[] & { x: string }>;
>T5 : Box<string>[]
>   : ^^^^^^^^^^^^^
>x : string
>  : ^^^^^^

// https://github.com/microsoft/TypeScript/issues/57744

type MustBeArray<T extends any[]> = T;
>MustBeArray : T
>            : ^

type Hmm<T extends any[]> = T extends number[] ?
>Hmm : Hmm<T>
>    : ^^^^^^

    MustBeArray<{ [I in keyof T]: 1 }> :
    never;

type X = Hmm<[3, 4, 5]>;
>X : [1, 1, 1]
>  : ^^^^^^^^^