From python/typeshed#7894.

When a container (list, set, tuple, or dict) literal expression is
used as an argument to an ov...

Co-authored-by: Keller Fabian Rudolf (CC-AD/EYC3) <[email protected]>

Deeply nested if/else expressions have a worst-case exponential behavior.

This will for insta...

Skip processing a type alias node and generate an error.

Fixes #12544.

When an invalid python executable is passed to mypy, show an error
message instead of crashing.

Detect if lxml is importable in the test suite, if it is not, then skip the report tests which
...

Borrow an operand such as `x.y` (attribute of a native class) in various contexts
when it's sa...

Fixes #11121.

If we have multiple native attribute access operations in succession, we
can borrow the tempora...

Use static analysis to find attributes that are always defined. Always defined
attributes don't...

Make sure the fullname of a named tuple defined within a method matches
the nesting of the defi...

This test case cover a recent change in functionality:
if an attribute is defined as an InitVar...

* gettext: Make GNUTranslations.CONTEXT not final (python/typeshed#7841)
* sqlite3: Avoid optio...

Adds a test case for a crash that was fixed by #12762. Closes #12527.

Closes #8703, which is a crash that was fixed by #12762

Source commit:
https://github.com/python/typeshed/commit/a27f15ef0eb12b961d0fb58f8615a3df901a91...

Move the attrs plugin to a later pass, so that we won't have placeholders. Fix
various issues r...

Previously we could export an invalid type for a lambda passed to an
overloaded function. We fi...

Run the plugin in a later pass to avoid placeholder nodes.

Fixes #11728.

The dataclass plugin could crash if it encountered a placeholder. Fix the issue by
running the ...

Changes behaviour of PatternChecker so that ValuePattern does not cover
the entire (non-literal...

Fixes #12164

Fixes #11780, fixes #11428

This adds a get_class_attribute_hook to plugins to modify attributes on classes (as opposed to t...

Co-authored-by: 97littleleaf11 <[email protected]>
Co-authored-by: Jingch...

Adds a more precise error message for a Callable annotation, if the
option --disallow-any-gener...

Fixes #12474

Fixes #12108

Co-authored-by: Marcel-ICMC <[email protected]>
Co-authored-by: Shantanu <1262...

Re-attempt of #10741
Ran: `pyupgrade --py36-plus $(fd -e py) --keep-runtime-typing`
I mostly o...

Done largely using https://github.com/ikamensh/flynt
I went over this pretty closely since I wa...

Re-attempt of #10741
Ran: `pyupgrade --py36-plus $(fd -e py) --keep-runtime-typing`
I mostly o...

Co-authored by: @chrisbeardy

`fast_dict_type` and `fast_container_type` only allowed Instance but not Tuple of Instances
whi...

Re-attempt of #10741
Ran: `pyupgrade --py36-plus $(fd -e py) --keep-runtime-typing`
I mostly o...

Re-attempt of #10741
Ran: `pyupgrade --py36-plus $(fd -e py) --keep-runtime-typing`
I mostly o...

Replace List with Dict to avoid O(n**2) behavior in `check_for_extra_actual_arguments`

This m...

`introduction.rst` has moved into `index.rst` in #12348.

Mypy thought that a variable annotated with P.args is not iterable, and
that a variable annota...

When profiling mypy over a large codebase, it can be useful
to know which files are slowest to ...

Implements basic inference for TypeVarTuple along with various check tests
verifying uses of T...

* errors: speedup for large error counts

We have a legacy codebase with many errors across ma...

Document some additional error codes and some general doc updates for
the 0.950 release.

Fixes #12633.

* Sync typeshed

Source commit:
https://github.com/python/typeshed/commit/5dad506bf20ed5b3ddf...

I've seen crashes like this, which might be caused by not
fixing up some FakeInfos:

```
F...

Closes #5551 (the bug in that issue was fixed by #12590)

They weren't serialized before. Manually written serialization
code is a pain to keep up-to-date.

This adds the TypeVarTupleType type node and basic semanal/glue.

Type checking involving it w...

Improve docs and fix typos

This adds minimal support for a TypeVarTupleExpr node, gated behind the
flag to enable incomple...

Recent attempts at speedup introduced some convoluted logic that both
reduced accuracy and caus...

This was originally written by @A5rocks in #11657.

Related to #12590.

This avoids confusion between type variables of two classes, which can
happen at least in some ...

Closes #12606

Co-authored-by: hauntsaninja <>
Co-authored-by: Shantanu <[email protected]...

As a followup to #9394 address a few more O(n**2) behaviors
caused by decomposing enums into un...

Noticed in python/typeshed#7655 that it was incorrectly inferring list[Any]
in all cases. This ...

This always existed in typing_extensions, but was an alias for
typing.overload. With python/typ...

Source commit:
https://github.com/python/typeshed/commit/d09689f8115173e3b0b04365f5233164014a7a...

See python/cpython#30843.

The implementation mostly follows that of cast(). It relies on
`my...

Fixes #12542.

This allows parameters to constrain to Any.

GitHub has dropped support for the unauthenticated git protocol. See
https://github.blog/2021-0...

Linking #12554

Co-authored-by: hauntsaninja <>

From python/typeshed#7614.

It is not necessary for instance variables to have the fget attrbute
(e.g. instance variable in...

Source commit:
https://github.com/python/typeshed/commit/3c85f36b7f9afd599409d10a214aafdecf38251e

Mypyc is bad at compiling nested functions. In one use case
we were spending 7% of the mypy run...

This tweaks a change made in #12539 that may have slowed things
down. The behavior introduced i...

This is very performance critical. Implement a few micro-optimizations
to speed caching a bit. ...

It can be a bottleneck in some use cases.

This shows up as a bottleneck in some use cases, based on
profiling.

This should help with u...

Don't rely on `object.__slots__` being defined, since it's not
defined at runtime (and currentl...

This PR adds a new Parameters proper type to represent ParamSpec parameters
(more about this i...

#11962 can generate large unions with many Instance types with
last_known_value set. This cause...

This avoids creating a new int object every time
we evaluate an integer literal in a context th...

`CPyDict_SetDefaultWithNone` doesn't return a borrowed reference,
since it just calls `CPyDict_...

It's not used for anything.