“no-matching-overload” instantiating logging.StreamHandler

[turian]

Summary

error: lint\:no-matching-overload: No overload of bound method `__init__` matches arguments

for this minimal example:

import logging
h = logging.StreamHandler()          # ← error

Why this is unexpected

• The CPython docs and runtime accept a zero-argument constructor that defaults to sys.stderr.

• typeshed’s logging/__init__.pyi reflects that signature:

    class StreamHandler(Handler):
        def __init__(self, stream: IO[str] | None = ...) -> None: ...
  

• Ty’s own stub—red_knot/builtins/logging.pyi—still exposes the old overloads that take filename | PathLike and therefore rejects the common no-argument form.

Because of that divergence, projects that pass mypy/ruff/mkdocs etc. must add:

handler = logging.StreamHandler()          # ty: ignore

and then hit issue #130 when the code is split across lines.

Repro

1. echo 'import logging; logging.StreamHandler()' > t.py
2. ty check t.py

Expected

No diagnostics.

Actual

lint:no-matching-overload

Proposed fix

Import logging and update the StreamHandler overloads in Ty’s stdlib stubs to match typeshed (i.e., make the first positional argument an optional IO[str], default None).

---

This bug is separate from #130 (“unused suppression for type: ignore”) – that issue only appears because we’re forced to ignore this stub mismatch.

Version

0.0.0-alpha.7 (905a3e1 2025-05-07)

[my1e5]

Is this issue solved?

https://play.ty.dev/e7169c70-7716-4ed4-aa4e-cb2e74510acf

import logging
import sys

logging.StreamHandler(stream=sys.stdout)

$ uvx ty check foo.py
error: lint:no-matching-overload: No overload of bound method `__init__` matches arguments
 --> foo.py:4:1
  |
2 | import sys
3 |
4 | logging.StreamHandler(stream=sys.stdout)
  | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  |
info: `lint:no-matching-overload` is enabled by default

Found 1 diagnostic

[carljm]

Ty doesn't have its own stubs, it uses typeshed.

I suspect the issue here is that we are actually failing to match on the self annotations of those overloads, for some generics-related reason.

(This issue also highlights that our diagnostics on a failed call to an overloaded function need some attention: #274)

[BlinkyStitt]

i also see this error with this simple code:

with tempfile.TemporaryDirectory() as temp_dir:
    pass