This updates the `Signature` and `CallBinding` machinery to support
multiple overloads for a callable. This is currently only used for
`KnownFunction`s that we special-case in our type inference code. It
does **_not_** yet update the semantic index builder to handle
`@overload` decorators and construct a multi-signature `Overloads`
instance for real Python functions.
While I was here, I updated many of the `try_call` special cases to use
signatures (possibly overloaded ones now) and `bind_call` to check
parameter lists. We still need some of the mutator methods on
`OverloadBinding` for the special cases where we need to update return
types based on some Rust code.
Resolves https://github.com/astral-sh/ruff/issues/14547 by delegating
narrowing to `E` for `bool(E)` where `E` is some expression.
This change does not include other builtin class constructors which
should also work in this position, like `int(..)` or `float(..)`, as the
original issue does not mention these. It should be easy enough to add
checks for these as well if we want to.
I don't see a lot of markdown tests for malformed input, maybe there's a
better place for the no args and too many args cases to go?
I did see after the fact that it looks like this task was intended for a
new hire.. my apologies. I got here from
https://github.com/astral-sh/ruff/issues/13694, which is marked
help-wanted.
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Co-authored-by: David Peter <mail@david-peter.de>