Use lazy initialization to avoid method calls in `__init__`. This allows
mypyc to infer more al...

This makes mypy a bit faster and the implementation seems a little
cleaner as well.

(Various...

These errors are already reported by the (new) semantic analyzer.

I've discovered this while...

This one would occur because we set the errors module with global
options, instead of per-modul...

Enums are exploded into Union of Literal when narrowed.

Conditional branches on enum values c...

I want to get rid of all the bogus types eventually.

Resolves the following warning:

![image](https://user-images.githubusercontent.com/1350584/20...

This helps with await-related errors introduced in #12958, in
particular, which are expensive t...

This makes the implementation of hasattr() checks faster (introduced in
#13544).

In particul...

Stubtest currently has both false-positives and false-negatives when it
comes to verifying cons...

The docs build is currently failing on `master`: see e.g.
https://github.com/python/mypy/action...

The script compiles some mypy commits in parallel and then measures how
long each version takes...

Mypyc can't optimize context managers yet, so it's best to avoid them in
hot code paths.

Thi...

This helps mypyc, since accessing mutable attributes of singleton
instances is faster than acce...

I measured a 1% performance improvement in self check.

Switch :py:func:type to py:class:type in type_narrowing.rst. The former does not render properly...

This reverts commit dbcbb3f5c3ef791c98088da0bd1dfa6cbf51f301.

The indentation in generated co...

`in` could narrow unions of TypeDicts, e.g.
```python
class A(TypedDict)
foo: int

@fina...

Use a faster type query visitor and reuse visitor across calls.

This should speed up type che...

Mypyc isn't good at compiling nested functions, and this one was in one
of the hottest code pat...

Avoid the use of a nested function, which are a bit slow when compiled
with mypyc. Also avoid a...

Only perform type variable freshening if it's needed, i.e. there is a
nested generic callable, ...

The implementation copied lots of callable types even when not using
the new feature, which was...

Removals from `stubinfo.py`:
- `atomicwrites` is archived and deprecated at runtime; stubs were...

Enable the `--debug-serialize` option to help catch issues during
serialization which would nor...

Currently, `mypy_primer` sets `--cache-dir=/dev/null` which disables
cache generation. This can...

This PR only adds the existing `TypeVar` support for the
`typing_extensions` variant.
I.e. it ...

In particular, ran into an issue with an `if TYPE_CHECKING` case, so I
added a test for that.

A similar case was addressed in #14176 but I missed the part where it
doesn't need to be define...

This adds support for try/except/finally/else check.

The implementation ended up pretty compl...

Now mypy can figure out the values of final variables even if the
initializer has some operatio...

Source commit:

https://github.com/python/typeshed/commit/9bddd3a3f1abfaf6335c2139a77ff1ff69eb...

Fixed #13103

Adds a check to class attribute access to ensure it isn't a defined
slot.

`#if PY_MAJOR_VERSION >= 3 && PY_MINOR_VERSION >= 7`

For example, this is true for Python 3.7...

This came up in https://github.com/python/typeshed/pull/9347

Rename `partially-defined` to `possibly-undefined` and `use-before-def`
to `used-before-def`.
...

Last time i checked it wasn't the 1960's. So I think the CI could be
colorized.

Configured p...

Now that the fallback is available, we can construct TupleTypes instead
of TypeLists which will...

A tuple such as `tuple[i64, i64]` can't have a dedicated error value, so
use overlapping error ...

A quick patch to enable the following scenario:

```python
@define
class C:
a: Final[in...

Now these two samples are identical:

```ini
[mypy]
enable_error_code =
truthy-bool,
r...

Now that daemon is more mature and stable I think we can attract some
more attention to it.

Several issues that I have seen recently could be fixed by
enabling/disabling an error code. I ...

Ref #13685

cc @Michael0x2a @JukkaL @hauntsaninja

Co-authored-by: Alex Waygood <Alex.Waygo...

See https://github.com/lbolla/emacs-flycheck-mypy#readme

Closes https://github.com/mypyc/mypyc/issues/911

Like the title says, this PR adds support fo...

Previously --fast-exit would actually disable the fast_exit option. Now
it behaves as expected ...

We want to eventually decomission the use of TypeList for
constraints/expanded values of TypeVa...

Fixes #14223

Sync typeshed

Source commit:

https://github.com/python/typeshed/commit/87d2683ef974ef6d6d8...

The goal of partially-defined check is to detect variables that could be
undefined but semantic...

This is a workaround until we implement better handling for variables
undefined in global scope...

We have multiple of these in `typeshed`:
https://github.com/python/typeshed/search?q=__warningr...

Previously, we would ignore any class definitions and would fail to
detect undefined classes an...

Fix typo - remove an unneeded period

https://mypy.readthedocs.io/en/stable/running_mypy.htm...

Most types can be considered as callables, constructing the type itself.
When a constraint was ...

Fixes #14199

This is straightforward, just use the same logic as for regular (user
defined)...

Ref #14201

We should not check untyped functions unless --check-untyped-defs is
set.

This is part of th...

In order to know to use `partially-defined` code vs `use-before-def`, we
had to check if a vari...

`else` in loops is executed if the loop didn't exit via a raise, return,
or a break. Therefore,...

This was incorrect for a few callsites. I refactored the code to make it
harder to make a mista...

Helps with python/typeshed#8988.

These are the issues that I've found using mypy-primer.

You should be able to review this PR ...

We previously used `use-before-def` code here but this commit switched
it to use `partially-def...

Fixes #6715

Fix is straightforward, currently we assume that if we have a variable
in MRO, ...

Fix type aliases like these:
```
T = tuple[int, str]
```
Type applications involving fixed-l...

Fix aliases like this and other aliases involving new-style unions:
```
A = type[int] | str
`...

Fixes #6730

Currently `expand_type()` is inherently recursive, going through
`expand_type` -...

Fixes #11855
Fixes #7084
Fixes #10445
Should fix #4987

After thinking about this for some...

This should help with the investigation of tricky performance
regressions like https://github.c...

This gives around 1% speed-up on self check, and may give even more for
code that is heavy on o...

Windows wheels for Python 3.11 are not included in the release, and
`cibuildwheels` cannot buil...

This implements a check when a variable is defined before use. Something
like:
```python
def ...

This adds support for unreachable blocks in `partially-defined` check.

Currently, this only s...

Fixes #4805
Fixes #13936

It is known that mypy can overuse outer type context sometimes
(es...

Fixes #5865

Looks quite easy and safe, unless I am missing something. Most changes
in the d...

While working on another PR I noticed that current behavior of
`has_recursive_types()` is incon...

Fixes #14137

Fix is trivial, I just forgot to call `super()` in one of my previous
PRs.

Fixes #14139

See https://github.com/python/mypy/pull/14130 for context.

Btw it looks like these `Any` repo...

- Added missing cast import
- Changed revealed type

Co-authored-by: Shantanu <12621235+haunt...

Fixes #12483
Fixes https://github.com/python/typeshed/issues/7564
Ref #12841

The fix is str...

Ref #12840

Fixes #14098

Having invalid statements in a NamedTuple is almost like a syntax error,
we ca...

Easy crash to repro: `mypy --any-exprs-report=out -c 'pass' --show-traceback`

Since the plugin provides superior type checking:
https://github.com/python/mypy/pull/13987#iss...

Source commit:

https://github.com/python/typeshed/commit/263427f438aa7d3f0bd570f671ecba9299c1...

Closes #14059

Fixes #10482

This is not very principled, but should work except people will want to
explic...

Fixes #14108

This fixes both new and old style of working with self types. After all
I fixe...

Fixes #13903

The fix is straightforward, the formal to actual map needs to be
refreshed twi...

This requires handling more cases in the various places that we
previously modified to support ...

Addresses the non-crash part of #10244 (and similar situations).

The `freshen_function_type_v...