Update mypy to 1.11.1

[pyup-bot]

This PR updates mypy from 1.7.1 to 1.11.1.

Changelog

1.11

We’ve just uploaded mypy 1.11 to the Python Package Index ([PyPI](https://pypi.org/project/mypy/)). Mypy is a static type checker for Python. This release includes new features, performance improvements and bug fixes. You can install it as follows:

 python3 -m pip install -U mypy

You can read the full documentation for this release on [Read the Docs](http://mypy.readthedocs.io).

Support Python 3.12 Syntax for Generics (PEP 695)

Mypy now supports the new type parameter syntax introduced in Python 3.12 ([PEP 695](https://peps.python.org/pep-0695/)).
This feature is still experimental and must be enabled with the `--enable-incomplete-feature=NewGenericSyntax` flag, or with `enable_incomplete_feature = NewGenericSyntax` in the mypy configuration file.
We plan to enable this by default in the next mypy feature release.

This example demonstrates the new syntax:

python
Generic function
def f[T](x: T) -> T: ...

reveal_type(f(1))   Revealed type is 'int'

Generic class
class C[T]:
 def __init__(self, x: T) -> None:
    self.x = x

c = C('a')
reveal_type(c.x)   Revealed type is 'str'

Type alias
type A[T] = C[list[T]]


This feature was contributed by Jukka Lehtosalo.


Support for `functools.partial`

Mypy now type checks uses of `functools.partial`. Previously mypy would accept arbitrary arguments.

This example will now produce an error:

python
from functools import partial

def f(a: int, b: str) -> None: ...

g = partial(f, 1)

Argument has incompatible type "int"; expected "str"
g(11)


This feature was contributed by Shantanu (PR [16939](https://github.com/python/mypy/pull/16939)).


Stricter Checks for Untyped Overrides

Past mypy versions didn't check if untyped methods were compatible with overridden methods. This would result in false negatives. Now mypy performs these checks when using `--check-untyped-defs`.

For example, this now generates an error if using `--check-untyped-defs`:

python
class Base:
 def f(self, x: int = 0) -> None: ...

class Derived(Base):
  Signature incompatible with "Base"
 def f(self): ...


This feature was contributed by Steven Troxler (PR [17276](https://github.com/python/mypy/pull/17276)).


Type Inference Improvements

The new polymorphic inference algorithm introduced in mypy 1.5 is now used in more situations. This improves type inference involving generic higher-order functions, in particular.

This feature was contributed by Ivan Levkivskyi (PR [17348](https://github.com/python/mypy/pull/17348)).

Mypy now uses unions of tuple item types in certain contexts to enable more precise inferred types. Example:

python
for x in (1, 'x'):
  Previously inferred as 'object'
 reveal_type(x)   Revealed type is 'int | str'


This was also contributed by Ivan Levkivskyi (PR [17408](https://github.com/python/mypy/pull/17408)).


Improvements to Detection of Overlapping Overloads

The details of how mypy checks if two `overload` signatures are unsafely overlapping were overhauled. This both fixes some false positives, and allows mypy to detect additional unsafe signatures.

This feature was contributed by Ivan Levkivskyi (PR [17392](https://github.com/python/mypy/pull/17392)).


Better Support for Type Hints in Expressions

Mypy now allows more expressions that evaluate to valid type annotations in all expression contexts. The inferred types of these expressions are also sometimes more precise. Previously they were often `object`.

This example uses a union type that includes a callable type as an expression, and it no longer generates an error:

python
from typing import Callable

print(Callable[[], int] | None)   No error


This feature was contributed by Jukka Lehtosalo (PR [17404](https://github.com/python/mypy/pull/17404)).


Mypyc Improvements

Mypyc now supports the new syntax for generics introduced in Python 3.12 (see above). Another notable improvement is signficantly faster basic operations on `int` values.

* Support Python 3.12 syntax for generic functions and classes (Jukka Lehtosalo, PR [17357](https://github.com/python/mypy/pull/17357))
* Support Python 3.12 type alias syntax (Jukka Lehtosalo, PR [17384](https://github.com/python/mypy/pull/17384))
* Fix ParamSpec (Shantanu, PR [17309](https://github.com/python/mypy/pull/17309))
* Inline fast paths of integer unboxing operations (Jukka Lehtosalo, PR [17266](https://github.com/python/mypy/pull/17266))
* Inline tagged integer arithmetic and bitwise operations (Jukka Lehtosalo, PR [17265](https://github.com/python/mypy/pull/17265))
* Allow specifying primitives as pure (Jukka Lehtosalo, PR [17263](https://github.com/python/mypy/pull/17263))


Changes to Stubtest
* Ignore `_ios_support` (Alex Waygood, PR [17270](https://github.com/python/mypy/pull/17270))
* Improve support for Python 3.13 (Shantanu, PR [17261](https://github.com/python/mypy/pull/17261))


Changes to Stubgen
* Gracefully handle invalid `Optional` and recognize aliases to PEP 604 unions (Ali Hamdan, PR [17386](https://github.com/python/mypy/pull/17386))
* Fix for Python 3.13 (Jelle Zijlstra, PR [17290](https://github.com/python/mypy/pull/17290))
* Preserve enum value initialisers (Shantanu, PR [17125](https://github.com/python/mypy/pull/17125))


Miscellaneous New Features
* Add error format support and JSON output option via `--output json` (Tushar Sadhwani, PR [11396](https://github.com/python/mypy/pull/11396))
* Support `enum.member` in Python 3.11+ (Nikita Sobolev, PR [17382](https://github.com/python/mypy/pull/17382))
* Support `enum.nonmember` in Python 3.11+ (Nikita Sobolev, PR [17376](https://github.com/python/mypy/pull/17376))
* Support `namedtuple.__replace__` in Python 3.13 (Shantanu, PR [17259](https://github.com/python/mypy/pull/17259))
* Support `rename=True` in collections.namedtuple (Jelle Zijlstra, PR [17247](https://github.com/python/mypy/pull/17247))
* Add support for `__spec__` (Shantanu, PR [14739](https://github.com/python/mypy/pull/14739))


Changes to Error Reporting
* Mention `--enable-incomplete-feature=NewGenericSyntax` in messages (Shantanu, PR [17462](https://github.com/python/mypy/pull/17462))
* Do not report plugin-generated methods with `explicit-override` (sobolevn, PR [17433](https://github.com/python/mypy/pull/17433))
* Use and display namespaces for function type variables (Ivan Levkivskyi, PR [17311](https://github.com/python/mypy/pull/17311))
* Fix false positive for Final local scope variable in Protocol (GiorgosPapoutsakis, PR [17308](https://github.com/python/mypy/pull/17308))
* Use Never in more messages, use ambiguous in join (Shantanu, PR [17304](https://github.com/python/mypy/pull/17304))
* Log full path to config file in verbose output (dexterkennedy, PR [17180](https://github.com/python/mypy/pull/17180))
* Added `[prop-decorator]` code for unsupported property decorators (14461) (Christopher Barber, PR [16571](https://github.com/python/mypy/pull/16571))
* Suppress second error message with `:=` and `[truthy-bool]` (Nikita Sobolev, PR [15941](https://github.com/python/mypy/pull/15941))
* Generate error for assignment of functional Enum to variable of different name (Shantanu, PR [16805](https://github.com/python/mypy/pull/16805))
* Fix error reporting on cached run after uninstallation of third party library (Shantanu, PR [17420](https://github.com/python/mypy/pull/17420))


Fixes for Crashes
* Fix daemon crash on invalid type in TypedDict (Ivan Levkivskyi, PR [17495](https://github.com/python/mypy/pull/17495))
* Fix crash and bugs related to `partial()` (Ivan Levkivskyi, PR [17423](https://github.com/python/mypy/pull/17423))
* Fix crash when overriding with unpacked TypedDict (Ivan Levkivskyi, PR [17359](https://github.com/python/mypy/pull/17359))
* Fix crash on TypedDict unpacking for ParamSpec (Ivan Levkivskyi, PR [17358](https://github.com/python/mypy/pull/17358))
* Fix crash involving recursive union of tuples (Ivan Levkivskyi, PR [17353](https://github.com/python/mypy/pull/17353))
* Fix crash on invalid callable property override (Ivan Levkivskyi, PR [17352](https://github.com/python/mypy/pull/17352))
* Fix crash on unpacking self in NamedTuple (Ivan Levkivskyi, PR [17351](https://github.com/python/mypy/pull/17351))
* Fix crash on recursive alias with an optional type (Ivan Levkivskyi, PR [17350](https://github.com/python/mypy/pull/17350))
* Fix crash on type comment inside generic definitions (Bénédikt Tran, PR [16849](https://github.com/python/mypy/pull/16849))


Changes to Documentation
* Use inline config in documentation for optional error codes (Shantanu, PR [17374](https://github.com/python/mypy/pull/17374))
* Use lower-case generics in documentation (Seo Sanghyeon, PR [17176](https://github.com/python/mypy/pull/17176))
* Add documentation for show-error-code-links (GiorgosPapoutsakis, PR [17144](https://github.com/python/mypy/pull/17144))
* Update CONTRIBUTING.md to include commands for Windows (GiorgosPapoutsakis, PR [17142](https://github.com/python/mypy/pull/17142))


Other Notable Improvements and Fixes
* Fix ParamSpec inference against TypeVarTuple (Ivan Levkivskyi, PR [17431](https://github.com/python/mypy/pull/17431))
* Fix explicit type for `partial` (Ivan Levkivskyi, PR [17424](https://github.com/python/mypy/pull/17424))
* Always allow lambda calls (Ivan Levkivskyi, PR [17430](https://github.com/python/mypy/pull/17430))
* Fix isinstance checks with PEP 604 unions containing None (Shantanu, PR [17415](https://github.com/python/mypy/pull/17415))
* Fix self-referential upper bound in new-style type variables (Ivan Levkivskyi, PR [17407](https://github.com/python/mypy/pull/17407))
* Consider overlap between instances and callables (Ivan Levkivskyi, PR [17389](https://github.com/python/mypy/pull/17389))
* Allow new-style self-types in classmethods (Ivan Levkivskyi, PR [17381](https://github.com/python/mypy/pull/17381))
* Fix isinstance with type aliases to PEP 604 unions (Shantanu, PR [17371](https://github.com/python/mypy/pull/17371))
* Properly handle unpacks in overlap checks (Ivan Levkivskyi, PR [17356](https://github.com/python/mypy/pull/17356))
* Fix type application for classes with generic constructors (Ivan Levkivskyi, PR [17354](https://github.com/python/mypy/pull/17354))
* Update `typing_extensions` to >=4.6.0 to fix Python 3.12 error (Ben Brown, PR [17312](https://github.com/python/mypy/pull/17312))
* Avoid "does not return" error in lambda (Shantanu, PR [17294](https://github.com/python/mypy/pull/17294))
* Fix bug with descriptors in non-strict-optional mode (Max Murin, PR [17293](https://github.com/python/mypy/pull/17293))
* Don’t leak unreachability from lambda body to surrounding scope (Anders Kaseorg, PR [17287](https://github.com/python/mypy/pull/17287))
* Fix issues with non-ASCII characters on Windows (Alexander Leopold Shon, PR [17275](https://github.com/python/mypy/pull/17275))
* Fix for type narrowing of negative integer literals (gilesgc, PR [17256](https://github.com/python/mypy/pull/17256))
* Fix confusion between .py and .pyi files in mypy daemon (Valentin Stanciu, PR [17245](https://github.com/python/mypy/pull/17245))
* Fix type of `tuple[X, Y]` expression (urnest, PR [17235](https://github.com/python/mypy/pull/17235))
* Don't forget that a `TypedDict` was wrapped in `Unpack` after a `name-defined` error occurred (Christoph Tyralla, PR [17226](https://github.com/python/mypy/pull/17226))
* Mark annotated argument as having an explicit, not inferred type (bzoracler, PR [17217](https://github.com/python/mypy/pull/17217))
* Don't consider Enum private attributes as enum members (Ali Hamdan, PR [17182](https://github.com/python/mypy/pull/17182))
* Fix Literal strings containing pipe characters (Jelle Zijlstra, PR [17148](https://github.com/python/mypy/pull/17148))


Typeshed Updates

Please see [git log](https://github.com/python/typeshed/commits/main?after=6dda799d8ad1d89e0f8aad7ac41d2d34bd838ace+0&branch=main&path=stdlib) for full list of standard library typeshed stub changes.


Acknowledgements
Thanks to all mypy contributors who contributed to this release:

- Alex Waygood
- Alexander Leopold Shon
- Ali Hamdan
- Anders Kaseorg
- Ben Brown
- Bénédikt Tran
- bzoracler
- Christoph Tyralla
- Christopher Barber
- dexterkennedy
- gilesgc
- GiorgosPapoutsakis
- Ivan Levkivskyi
- Jelle Zijlstra
- Jukka Lehtosalo
- Marc Mueller
- Matthieu Devlin
- Michael R. Crusoe
- Nikita Sobolev
- Seo Sanghyeon
- Shantanu
- sobolevn
- Steven Troxler
- Tadeu Manoel
- Tamir Duberstein
- Tushar Sadhwani
- urnest
- Valentin Stanciu

I’d also like to thank my employer, Dropbox, for supporting mypy development.

1.10.1

- Fix error reporting on cached run after uninstallation of third party library (Shantanu, PR [17420](https://github.com/python/mypy/pull/17420))

Acknowledgements
Thanks to all mypy contributors who contributed to this release:

- Alex Waygood
- Ali Hamdan
- Edward Paget
- Evgeniy Slobodkin
- Hashem
- hesam
- Hugo van Kemenade
- Ihor
- James Braza
- Jelle Zijlstra
- jhance
- Jukka Lehtosalo
- Loïc Simon
- Marc Mueller
- Matthieu Devlin
- Michael R. Crusoe
- Nikita Sobolev
- Oskari Lehto
- Riccardo Di Maio
- Richard Si
- roberfi
- Roman Solomatin
- Sam Xifaras
- Shantanu
- Spencer Brown
- Srinivas Lade
- Tamir Duberstein
- youkaichao

I’d also like to thank my employer, Dropbox, for supporting mypy development.

1.10

We’ve just uploaded mypy 1.10 to the Python Package Index ([PyPI](https://pypi.org/project/mypy/)). Mypy is a static type checker for Python. This release includes new features, performance improvements and bug fixes. You can install it as follows:

 python3 -m pip install -U mypy

You can read the full documentation for this release on [Read the Docs](http://mypy.readthedocs.io).

Support TypeIs (PEP 742)

Mypy now supports `TypeIs` ([PEP 742](https://peps.python.org/pep-0742/)), which allows
functions to narrow the type of a value, similar to `isinstance()`. Unlike `TypeGuard`,
`TypeIs` can narrow in both the `if` and `else` branches of an if statement:

python
from typing_extensions import TypeIs

def is_str(s: object) -> TypeIs[str]:
 return isinstance(s, str)

def f(o: str | int) -> None:
 if is_str(o):
      Type of o is 'str'
     ...
 else:
      Type of o is 'int'
     ...


`TypeIs` will be added to the `typing` module in Python 3.13, but it
can be used on earlier Python versions by importing it from
`typing_extensions`.

This feature was contributed by Jelle Zijlstra (PR [16898](https://github.com/python/mypy/pull/16898)).

Support TypeVar Defaults (PEP 696)

[PEP 696](https://peps.python.org/pep-0696/) adds support for type parameter defaults.
Example:

python
from typing import Generic
from typing_extensions import TypeVar

T = TypeVar("T", default=int)

class C(Generic[T]):
...

x: C = ...
y: C[str] = ...
reveal_type(x)   C[int], because of the default
reveal_type(y)   C[str]


TypeVar defaults will be added to the `typing` module in Python 3.13, but they
can be used with earlier Python releases by importing `TypeVar` from
`typing_extensions`.

This feature was contributed by Marc Mueller (PR [16878](https://github.com/python/mypy/pull/16878)
and PR [16925](https://github.com/python/mypy/pull/16925)).

Support TypeAliasType (PEP 695)
As part of the initial steps towards implementing [PEP 695](https://peps.python.org/pep-0695/), mypy now supports `TypeAliasType`.
`TypeAliasType` provides a backport of the new `type` statement in Python 3.12.

python
type ListOrSet[T] = list[T] | set[T]


is equivalent to:

python
T = TypeVar("T")
ListOrSet = TypeAliasType("ListOrSet", list[T] | set[T], type_params=(T,))


Example of use in mypy:

python
from typing_extensions import TypeAliasType, TypeVar

NewUnionType = TypeAliasType("NewUnionType", int | str)
x: NewUnionType = 42
y: NewUnionType = 'a'
z: NewUnionType = object()   error: Incompatible types in assignment (expression has type "object", variable has type "int | str")  [assignment]

T = TypeVar("T")
ListOrSet = TypeAliasType("ListOrSet", list[T] | set[T], type_params=(T,))
a: ListOrSet[int] = [1, 2]
b: ListOrSet[str] = {'a', 'b'}
c: ListOrSet[str] = 'test'   error: Incompatible types in assignment (expression has type "str", variable has type "list[str] | set[str]")  [assignment]


`TypeAliasType` was added to the `typing` module in Python 3.12, but it can be used with earlier Python releases by importing from `typing_extensions`.

This feature was contributed by Ali Hamdan (PR [16926](https://github.com/python/mypy/pull/16926), PR [17038](https://github.com/python/mypy/pull/17038) and PR [17053](https://github.com/python/mypy/pull/17053))

Detect Additional Unsafe Uses of super()

Mypy will reject unsafe uses of `super()` more consistently, when the target has a
trivial (empty) body. Example:

python
class Proto(Protocol):
 def method(self) -> int: ...

class Sub(Proto):
 def method(self) -> int:
     return super().meth()   Error (unsafe)


This feature was contributed by Shantanu (PR [16756](https://github.com/python/mypy/pull/16756)).

Stubgen Improvements
- Preserve empty tuple annotation (Ali Hamdan, PR [16907](https://github.com/python/mypy/pull/16907))
- Add support for PEP 570 positional-only parameters (Ali Hamdan, PR [16904](https://github.com/python/mypy/pull/16904))
- Replace obsolete typing aliases with builtin containers (Ali Hamdan, PR [16780](https://github.com/python/mypy/pull/16780))
- Fix generated dataclass `__init__` signature (Ali Hamdan, PR [16906](https://github.com/python/mypy/pull/16906))

Mypyc Improvements

- Provide an easier way to define IR-to-IR transforms (Jukka Lehtosalo, PR [16998](https://github.com/python/mypy/pull/16998))
- Implement lowering pass and add primitives for int (in)equality (Jukka Lehtosalo, PR [17027](https://github.com/python/mypy/pull/17027))
- Implement lowering for remaining tagged integer comparisons (Jukka Lehtosalo, PR [17040](https://github.com/python/mypy/pull/17040))
- Optimize away some bool/bit registers (Jukka Lehtosalo, PR [17022](https://github.com/python/mypy/pull/17022))
- Remangle redefined names produced by async with (Richard Si, PR [16408](https://github.com/python/mypy/pull/16408))
- Optimize TYPE_CHECKING to False at Runtime (Srinivas Lade, PR [16263](https://github.com/python/mypy/pull/16263))
- Fix compilation of unreachable comprehensions (Richard Si, PR [15721](https://github.com/python/mypy/pull/15721))
- Don't crash on non-inlinable final local reads (Richard Si, PR [15719](https://github.com/python/mypy/pull/15719))

Documentation Improvements
- Import `TypedDict` from `typing` instead of `typing_extensions` (Riccardo Di Maio, PR [16958](https://github.com/python/mypy/pull/16958))
- Add missing `mutable-override` to section title (James Braza, PR [16886](https://github.com/python/mypy/pull/16886))

Error Reporting Improvements

- Use lower-case generics more consistently in error messages (Jukka Lehtosalo, PR [17035](https://github.com/python/mypy/pull/17035))

Other Notable Changes and Fixes
- Fix incorrect inferred type when accessing descriptor on union type (Matthieu Devlin, PR [16604](https://github.com/python/mypy/pull/16604))
- Fix crash when expanding invalid `Unpack` in a `Callable` alias (Ali Hamdan, PR [17028](https://github.com/python/mypy/pull/17028))
- Fix false positive when string formatting with string enum (roberfi, PR [16555](https://github.com/python/mypy/pull/16555))
- Narrow individual items when matching a tuple to a sequence pattern (Loïc Simon, PR [16905](https://github.com/python/mypy/pull/16905))
- Fix false positive from type variable within TypeGuard or TypeIs (Evgeniy Slobodkin, PR [17071](https://github.com/python/mypy/pull/17071))
- Improve `yield from` inference for unions of generators (Shantanu, PR [16717](https://github.com/python/mypy/pull/16717))
- Fix emulating hash method logic in `attrs` classes (Hashem, PR [17016](https://github.com/python/mypy/pull/17016))
- Add reverted typeshed commit that uses `ParamSpec` for `functools.wraps` (Tamir Duberstein, PR [16942](https://github.com/python/mypy/pull/16942))
- Fix type narrowing for `types.EllipsisType` (Shantanu, PR [17003](https://github.com/python/mypy/pull/17003))
- Fix single item enum match type exhaustion (Oskari Lehto, PR [16966](https://github.com/python/mypy/pull/16966))
- Improve type inference with empty collections (Marc Mueller, PR [16994](https://github.com/python/mypy/pull/16994))
- Fix override checking for decorated property (Shantanu, PR [16856](https://github.com/python/mypy/pull/16856))
- Fix narrowing on match with function subject (Edward Paget, PR [16503](https://github.com/python/mypy/pull/16503))
- Allow `+N` within `Literal[...]` (Spencer Brown, PR [16910](https://github.com/python/mypy/pull/16910))
- Experimental: Support TypedDict within `type[...]` (Marc Mueller, PR [16963](https://github.com/python/mypy/pull/16963))
- Experimtental: Fix issue with TypedDict with optional keys in `type[...]` (Marc Mueller, PR [17068](https://github.com/python/mypy/pull/17068))

Typeshed Updates

Please see [git log](https://github.com/python/typeshed/commits/main?after=6dda799d8ad1d89e0f8aad7ac41d2d34bd838ace+0&branch=main&path=stdlib) for full list of standard library typeshed stub changes.

1.9

We’ve just uploaded mypy 1.9 to the Python Package Index ([PyPI](https://pypi.org/project/mypy/)). Mypy is a static type checker for Python. This release includes new features, performance improvements and bug fixes. You can install it as follows:

 python3 -m pip install -U mypy

You can read the full documentation for this release on [Read the Docs](http://mypy.readthedocs.io).

Breaking Changes

Because the version of typeshed we use in mypy 1.9 doesn't support 3.7, neither does mypy 1.9. (Jared Hance, PR [16883](https://github.com/python/mypy/pull/16883))

We are planning to enable
[local partial types](https://mypy.readthedocs.io/en/stable/command_line.html#cmdoption-mypy-local-partial-types) (enabled via the
`--local-partial-types` flag) later this year by default. This change
was announced years ago, but now it's finally happening. This is a
major backward-incompatible change, so we'll probably include it as
part of the upcoming mypy 2.0 release. This makes daemon and
non-daemon mypy runs have the same behavior by default.

Local partial types can also be enabled in the mypy config file:

local_partial_types = True


We are looking at providing a tool to make it easier to migrate
projects to use `--local-partial-types`, but it's not yet clear whether
this is practical. The migration usually involves adding some
explicit type annotations to module-level and class-level variables.

Basic Support for Type Parameter Defaults (PEP 696)

This release contains new experimental support for type parameter
defaults ([PEP 696](https://peps.python.org/pep-0696)). Please try it
out! This feature was contributed by Marc Mueller.

Since this feature will be officially introduced in the next Python
feature release (3.13), you will need to import `TypeVar`, `ParamSpec`
or `TypeVarTuple` from `typing_extensions` to use defaults for now.

This example adapted from the PEP defines a default for `BotT`:
python
from typing import Generic
from typing_extensions import TypeVar

class Bot: ...

BotT = TypeVar("BotT", bound=Bot, default=Bot)

class Context(Generic[BotT]):
 bot: BotT

class MyBot(Bot): ...

type is Bot (the default)
reveal_type(Context().bot)
type is MyBot
reveal_type(Context[MyBot]().bot)


Type-checking Improvements
* Fix missing type store for overloads (Marc Mueller, PR [16803](https://github.com/python/mypy/pull/16803))
* Fix `'WriteToConn' object has no attribute 'flush'` (Charlie Denton, PR [16801](https://github.com/python/mypy/pull/16801))
* Improve TypeAlias error messages (Marc Mueller, PR [16831](https://github.com/python/mypy/pull/16831))
* Support narrowing unions that include `type[None]` (Christoph Tyralla, PR [16315](https://github.com/python/mypy/pull/16315))
* Support TypedDict functional syntax as class base type (anniel-stripe, PR [16703](https://github.com/python/mypy/pull/16703))
* Accept multiline quoted annotations (Shantanu, PR [16765](https://github.com/python/mypy/pull/16765))
* Allow unary + in `Literal` (Jelle Zijlstra, PR [16729](https://github.com/python/mypy/pull/16729))
* Substitute type variables in return type of static methods (Kouroche Bouchiat, PR [16670](https://github.com/python/mypy/pull/16670))
* Consider TypeVarTuple to be invariant (Marc Mueller, PR [16759](https://github.com/python/mypy/pull/16759))
* Add `alias` support to `field()` in `attrs` plugin (Nikita Sobolev, PR [16610](https://github.com/python/mypy/pull/16610))
* Improve attrs hashability detection (Tin Tvrtković, PR [16556](https://github.com/python/mypy/pull/16556))

Performance Improvements

* Speed up finding function type variables (Jukka Lehtosalo, PR [16562](https://github.com/python/mypy/pull/16562))

Documentation Updates

* Document supported values for `--enable-incomplete-feature` in "mypy --help" (Froger David, PR [16661](https://github.com/python/mypy/pull/16661))
* Update new type system discussion links (thomaswhaley, PR [16841](https://github.com/python/mypy/pull/16841))
* Add missing class instantiation to cheat sheet (Aleksi Tarvainen, PR [16817](https://github.com/python/mypy/pull/16817))
* Document how evil `--no-strict-optional` is (Shantanu, PR [16731](https://github.com/python/mypy/pull/16731))
* Improve mypy daemon documentation note about local partial types (Makonnen Makonnen, PR [16782](https://github.com/python/mypy/pull/16782))
* Fix numbering error (Stefanie Molin, PR [16838](https://github.com/python/mypy/pull/16838))
* Various documentation improvements (Shantanu, PR [16836](https://github.com/python/mypy/pull/16836))

Stubtest Improvements
* Ignore private function/method parameters when they are missing from the stub (private parameter names start with a single underscore and have a default) (PR [16507](https://github.com/python/mypy/pull/16507))
* Ignore a new protocol dunder (Alex Waygood, PR [16895](https://github.com/python/mypy/pull/16895))
* Private parameters can be omitted (Sebastian Rittau, PR [16507](https://github.com/python/mypy/pull/16507))
* Add support for setting enum members to "..." (Jelle Zijlstra, PR [16807](https://github.com/python/mypy/pull/16807))
* Adjust symbol table logic (Shantanu, PR [16823](https://github.com/python/mypy/pull/16823))
* Fix posisitional-only handling in overload resolution (Shantanu, PR [16750](https://github.com/python/mypy/pull/16750))

Stubgen Improvements
* Fix crash on star unpack of TypeVarTuple (Ali Hamdan, PR [16869](https://github.com/python/mypy/pull/16869))
* Use PEP 604 unions everywhere (Ali Hamdan, PR [16519](https://github.com/python/mypy/pull/16519))
* Do not ignore property deleter (Ali Hamdan, PR [16781](https://github.com/python/mypy/pull/16781))
* Support type stub generation for `staticmethod` (WeilerMarcel, PR [14934](https://github.com/python/mypy/pull/14934))

Acknowledgements

​Thanks to all mypy contributors who contributed to this release:

- Aleksi Tarvainen
- Alex Waygood
- Ali Hamdan
- anniel-stripe
- Charlie Denton
- Christoph Tyralla
- Dheeraj
- Fabian Keller
- Fabian Lewis
- Froger David
- Ihor
- Jared Hance
- Jelle Zijlstra
- Jukka Lehtosalo
- Kouroche Bouchiat
- Lukas Geiger
- Maarten Huijsmans
- Makonnen Makonnen
- Marc Mueller
- Nikita Sobolev
- Sebastian Rittau
- Shantanu
- Stefanie Molin
- Stephen Morton
- thomaswhaley
- Tin Tvrtković
- WeilerMarcel
- Wesley Collin Wright
- zipperer

I’d also like to thank my employer, Dropbox, for supporting mypy development.

1.8

We’ve just uploaded mypy 1.8 to the Python Package Index ([PyPI](https://pypi.org/project/mypy/)). Mypy is a static type checker for Python. This release includes new features, performance improvements and bug fixes. You can install it as follows:

 python3 -m pip install -U mypy

You can read the full documentation for this release on [Read the Docs](http://mypy.readthedocs.io).

Type-checking Improvements
* Do not intersect types in isinstance checks if at least one is final (Christoph Tyralla, PR [16330](https://github.com/python/mypy/pull/16330))
* Detect that `final` class without `__bool__` cannot have falsey instances (Ilya Priven, PR [16566](https://github.com/python/mypy/pull/16566))
* Do not allow `TypedDict` classes with extra keywords (Nikita Sobolev, PR [16438](https://github.com/python/mypy/pull/16438))
* Do not allow class-level keywords for `NamedTuple` (Nikita Sobolev, PR [16526](https://github.com/python/mypy/pull/16526))
* Make imprecise constraints handling more robust (Ivan Levkivskyi, PR [16502](https://github.com/python/mypy/pull/16502))
* Fix strict-optional in extending generic TypedDict (Ivan Levkivskyi, PR [16398](https://github.com/python/mypy/pull/16398))
* Allow type ignores of PEP 695 constructs (Shantanu, PR [16608](https://github.com/python/mypy/pull/16608))
* Enable `type_check_only` support for `TypedDict` and `NamedTuple` (Nikita Sobolev, PR [16469](https://github.com/python/mypy/pull/16469))

Performance Improvements
* Add fast path to analyzing special form assignments (Jukka Lehtosalo, PR [16561](https://github.com/python/mypy/pull/16561))

Improvements to Error Reporting
* Don't show documentation links for plugin error codes (Ivan Levkivskyi, PR [16383](https://github.com/python/mypy/pull/16383))
* Improve error messages for `super` checks and add more tests (Nikita Sobolev, PR [16393](https://github.com/python/mypy/pull/16393))
* Add error code for mutable covariant override (Ivan Levkivskyi, PR [16399](https://github.com/python/mypy/pull/16399))

Stubgen Improvements
* Preserve simple defaults in function signatures (Ali Hamdan, PR [15355](https://github.com/python/mypy/pull/15355))
* Include `__all__` in output (Jelle Zijlstra, PR [16356](https://github.com/python/mypy/pull/16356))
* Fix stubgen regressions with pybind11 and mypy 1.7 (Chad Dombrova, PR [16504](https://github.com/python/mypy/pull/16504))

Stubtest Improvements
* Improve handling of unrepresentable defaults (Jelle Zijlstra, PR [16433](https://github.com/python/mypy/pull/16433))
* Print more helpful errors if a function is missing from stub (Alex Waygood, PR [16517](https://github.com/python/mypy/pull/16517))
* Support `type_check_only` decorator (Nikita Sobolev, PR [16422](https://github.com/python/mypy/pull/16422))
* Warn about missing `__del__` (Shantanu, PR [16456](https://github.com/python/mypy/pull/16456))
* Fix crashes with some uses of `final` and `deprecated` (Shantanu, PR [16457](https://github.com/python/mypy/pull/16457))

Fixes to Crashes
* Fix crash with type alias to `Callable[[Unpack[Tuple[Any, ...]]], Any]` (Alex Waygood, PR [16541](https://github.com/python/mypy/pull/16541))
* Fix crash on TypeGuard in `__call__` (Ivan Levkivskyi, PR [16516](https://github.com/python/mypy/pull/16516))
* Fix crash on invalid enum in method (Ivan Levkivskyi, PR [16511](https://github.com/python/mypy/pull/16511))
* Fix crash on unimported Any in TypedDict (Ivan Levkivskyi, PR [16510](https://github.com/python/mypy/pull/16510))

Documentation Updates
* Update soft-error-limit default value to -1 (Sveinung Gundersen, PR [16542](https://github.com/python/mypy/pull/16542))
* Support Sphinx 7.x (Michael R. Crusoe, PR [16460](https://github.com/python/mypy/pull/16460))

Other Notable Changes and Fixes
* Allow mypy to output a junit file with per-file results (Matthew Wright, PR [16388](https://github.com/python/mypy/pull/16388))

Typeshed Updates

Please see [git log](https://github.com/python/typeshed/commits/main?after=4a854366e03dee700109f8e758a08b2457ea2f51+0&branch=main&path=stdlib) for full list of standard library typeshed stub changes.

Acknowledgements

​Thanks to all mypy contributors who contributed to this release:

- Alex Waygood
- Ali Hamdan
- Chad Dombrova
- Christoph Tyralla
- Ilya Priven
- Ivan Levkivskyi
- Jelle Zijlstra
- Jukka Lehtosalo
- Marcel Telka
- Matthew Wright
- Michael R. Crusoe
- Nikita Sobolev
- Ole Peder Brandtzæg
- robjhornby
- Shantanu
- Sveinung Gundersen
- Valentin Stanciu

I’d also like to thank my employer, Dropbox, for supporting mypy development.

Posted by Wesley Collin Wright

Links

• PyPI: https://pypi.org/project/mypy
• Changelog: https://data.safetycli.com/changelogs/mypy/
• Homepage: https://www.mypy-lang.org/

[pyup-bot]

Closing this in favor of #7741