dmypy suggest --no-any still gives suggestion with `Any`

[asottile-sentry]

Bug Report

I expect --no-any to forbid Any... however...

To Reproduce

def f(x):
    if not isinstance(x, dict):
        raise AssertionError
    return x

[mypy]
check_untyped_defs = true

Expected Behavior

$ dmypy run .
...
$ dmypy suggest t.f --no-any
No guesses that match criteria!

Actual Behavior

$ dmypy suggest t.f --no-any
(object) -> typing.Dict[Any, Any]

Your Environment

• Mypy version used: 1.15.0
• Mypy command-line flags: see above
• Mypy configuration options from mypy.ini (and other config files): see above
• Python version used: 3.13.

[brianschubert]

Look a quick look. This happens because the type of Any in the dict[Any, Any] type produced by isinstance(x, dict) is TypeOfAny.special_form, which ignored for the purposes of computing the "Anyness" of the return type. I don't think we can easily include special_form Anys in the "Anyness" calculation, since those crop up in other places that we definitely wouldn't want to count towards Anyness (e.g. most tuple types have tuple[Any, ...] as a fallback, which would be detected by the current logic). Possibly we could tweak get_isinstance_type to produce a different type of Any for isinstance(x, dict), but I'm not sure if that would have other adverse consequences

[A5rocks]

Maybe --no-any shouldn't use that measure of whether a type has an Any? It probably has stricter guarantees.