In 5bfc0f960b, risky casting was invoked
as a way to show there is an issue here. However, it is not always
possible to use a string. For instance, there is no such thing as this
in PHP: ["1" => "whatever"]. If you try to create such an array, you
will obtain [1 => "whatever"] instead.
Ironically, this was copied in jetbrains/phpstorm, which is used in
PHPStan, which exhibited that false positive.
See https://github.com/JetBrains/phpstorm-stubs/pull/1454