Feature request: option that completely disallows typing.cast

Feature

An option that disallows use of typing.cast, eg --disallow-casts

Pitch

cast() gets around static type safety without ensuring dynamic type correctness. Sometimes you have to use it—you know how it is—but it's not ideal. (For instance, mypy documentation seems to imply the main use of cast is when the typechecker or type annotations aren't quite good enough.) That means, in my opinion, cast is a great candidate to have a option disallowing its use, to ensure code quality in codebases where it is not needed.

I also think this option should be enabled in strict mode, but I suspect other people might disagree.

This proposal is distinct from the --warn-redundant-casts option that already exists, but is somewhat similar.

Inizia esaminando come è implementata l’opzione esistente --warn-redundant-casts e leggi la discussione sul fatto che questa debba rientrare nello strict mode. Definisci la gestione prevista di typing.cast e il relativo comportamento di configurazione, quindi verifica che la nuova opzione rifiuti i cast e che il comportamento scelto per lo strict mode sia coperto dai test.