Argument of type 'readonly number[]' is not assignable to parameter of type 'any[]'

[horyzont85]

Describe the bug

When I use:
check("foo").isIn(myArray)
where myArray is readonly array then I got an error:

Argument of type 'readonly number[]' is not assignable to parameter of type 'any[]'.
The type 'readonly number[]' is 'readonly' and cannot be assigned to the mutable type 'any[]'.ts(2345)

Expected behavior

isIn shouldn't report an error for readonly arrays.

Express-validator version:

• Version: 6.12.0

[fedeci]

Hi @horyzont85, which version of typescript are you using? Could you share your tsconfig.json?

[gustavohenke]

The bug makes sense to me -- we use readonly arrays all the time at work. readonly any[] is different from any[]:
https://www.typescriptlang.org/play?#code/MYewdgzgLgBAhgJwQLhggpnAJuANgT3jHwG0BdGAXhhIEYAaGAJkYGYyBuAKADMBXMMCgBLcDBwBlEAFt0UABbCwAcwAUSgA58oqOMXIBKGAG8Avl0ky5ilasQIDHIA

[gustavohenke]

Fixed in v6.12.1.