Merge remote-tracking branch 'upstream/master' into invalidvarcall

Author: hauntsaninja

.github/workflows/mypy_primer.yml

@@ -39,7 +39,7 @@ jobs:
           persist-credentials: false
       - uses: actions/setup-python@v5
         with:
-          python-version: "3.13"
+          python-version: "3.14"
       - name: Install dependencies
         run: |
           python -m pip install -U pip

.github/workflows/test.yml

@@ -59,6 +59,12 @@ jobs:
           toxenv: py
           tox_extra_args: "-n 4"
           test_mypyc: true
+        - name: Test suite with py314t-ubuntu, mypyc-compiled
+          python: '3.14t'
+          os: ubuntu-24.04-arm
+          toxenv: py
+          tox_extra_args: "-n 4"
+          test_mypyc: true
         - name: Test suite with py314-windows-64
           python: '3.14'
           os: windows-latest
@@ -95,6 +101,18 @@ jobs:
         #   tox_extra_args: "-n 4 mypyc/test/test_run.py mypyc/test/test_external.py"
         #   debug_build: true
 
+        - name: Parallel tests with py314-ubuntu, interpreted
+          python: '3.14'
+          os: ubuntu-24.04-arm
+          toxenv: py
+          tox_extra_args: "-n 4 --mypy-num-workers=4 mypy/test/testcheck.py"
+        - name: Parallel tests with py314-ubuntu, mypyc-compiled
+          python: '3.14'
+          os: ubuntu-24.04-arm
+          toxenv: py
+          tox_extra_args: "-n 4 --mypy-num-workers=4 mypy/test/testcheck.py"
+          test_mypyc: true
+
         - name: Type check our own code (py310-ubuntu)
           python: '3.10'
           os: ubuntu-latest

CHANGELOG.md

@@ -11,6 +11,15 @@ Support for this will be dropped in the first half of 2026!
 
 Contributed by Marc Mueller (PR [20156](https://github.com/python/mypy/pull/20156)).
 
+### Removed flags `--force-uppercase-builtins` and `--force-union-syntax`
+
+The `--force-uppercase-builtins` flag was deprecated and has been a no-op since mypy 1.17.0.
+Since mypy has dropped support for Python 3.9, the `--force-union-syntax` flag is no longer
+necessary.
+
+Contributed by Marc Mueller (PR [20410](https://github.com/python/mypy/pull/20410))
+and (PR [20405](https://github.com/python/mypy/pull/20405)).
+
 ## Mypy 1.19
 
 We’ve just uploaded mypy 1.19.0 to the Python Package Index ([PyPI](https://pypi.org/project/mypy/)).
@@ -216,6 +225,17 @@ Related PRs:
 
 Please see [git log](https://github.com/python/typeshed/commits/main?after=ebce8d766b41fbf4d83cf47c1297563a9508ff60+0&branch=main&path=stdlib) for full list of standard library typeshed stub changes.
 
+### Mypy 1.19.1
+
+- Fix noncommutative joins with bounded TypeVars (Shantanu, PR [20345](https://github.com/python/mypy/pull/20345))
+- Respect output format for cached runs by serializing raw errors in cache metas (Ivan Levkivskyi, PR [20372](https://github.com/python/mypy/pull/20372))
+- Allow `types.NoneType` in match cases (A5rocks, PR [20383](https://github.com/python/mypy/pull/20383))
+- Fix mypyc generator regression with empty tuple (BobTheBuidler, PR [20371](https://github.com/python/mypy/pull/20371))
+- Fix crash involving Unpack-ed TypeVarTuple (Shantanu, PR [20323](https://github.com/python/mypy/pull/20323))
+- Fix crash on star import of redefinition (Ivan Levkivskyi, PR [20333](https://github.com/python/mypy/pull/20333))
+- Fix crash on typevar with forward ref used in other module (Ivan Levkivskyi, PR [20334](https://github.com/python/mypy/pull/20334))
+- Fail with an explicit error on PyPy (Ivan Levkivskyi, PR [20389](https://github.com/python/mypy/pull/20389))
+
 ### Acknowledgements
 
 Thanks to all mypy contributors who contributed to this release:
@@ -251,7 +271,7 @@ Thanks to all mypy contributors who contributed to this release:
 
 I’d also like to thank my employer, Dropbox, for supporting mypy development.
 
-## Mypy 1.18.1
+## Mypy 1.18
 
 We’ve just uploaded mypy 1.18.1 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

docs/source/additional_features.rst

@@ -135,7 +135,7 @@ Type annotations can be added as follows:
 
 .. code-block:: python
 
-    import attr
+    import attrs
 
     @attrs.define
     class A:

docs/source/command_line.rst

@@ -958,12 +958,6 @@ in error messages.
     useful or they may be overly noisy. If ``N`` is negative, there is
     no limit. The default limit is -1.
 
-.. option:: --force-union-syntax
-
-    Always use ``Union[]`` and ``Optional[]`` for union types
-    in error messages (instead of the ``|`` operator),
-    even on Python 3.10+.
-
 
 .. _incremental:
 

docs/source/config_file.rst

@@ -930,15 +930,6 @@ These options may only be set in the global section (``[mypy]``).
 
     Show absolute paths to files.
 
-.. confval:: force_union_syntax
-
-    :type: boolean
-    :default: False
-
-    Always use ``Union[]`` and ``Optional[]`` for union types
-    in error messages (instead of the ``|`` operator),
-    even on Python 3.10+.
-
 Incremental mode
 ****************
 

docs/source/error_code_list.rst

@@ -1151,6 +1151,25 @@ Warn about cases where a bytes object may be converted to a string in an unexpec
     print(f"The alphabet starts with {b!r}")  # The alphabet starts with b'abc'
     print(f"The alphabet starts with {b.decode('utf-8')}")  # The alphabet starts with abc
 
+.. _code-str-unpack:
+
+Check that ``str`` is not unpacked [str-unpack]
+---------------------------------------------------------
+
+It can sometimes be surprising that ``str`` is iterable, especially when unpacking
+in an assignment.
+
+Example:
+
+.. code-block:: python
+
+    def print_dict(d: dict[str, str]) -> int:
+        # We meant to do d.items(), but instead we're unpacking the str keys of d
+
+        # Error: Unpacking a string is disallowed
+        for k, v in d:
+            print(k, v)
+
 .. _code-overload-overlap:
 
 Check that overloaded functions don't overlap [overload-overlap]

misc/analyze_cache.py

@@ -7,8 +7,7 @@
 import os.path
 from collections import Counter
 from collections.abc import Iterable
-from typing import Any, Final
-from typing_extensions import TypeAlias as _TypeAlias
+from typing import Any, Final, TypeAlias as _TypeAlias
 
 ROOT: Final = ".mypy_cache/3.5"
 

misc/incremental_checker.py

@@ -44,8 +44,7 @@
 import textwrap
 import time
 from argparse import ArgumentParser, Namespace, RawDescriptionHelpFormatter
-from typing import Any, Final
-from typing_extensions import TypeAlias as _TypeAlias
+from typing import Any, Final, TypeAlias as _TypeAlias
 
 CACHE_PATH: Final = ".incremental_checker_cache.json"
 MYPY_REPO_URL: Final = "https://github.com/python/mypy.git"

misc/perf_checker.py

@@ -8,7 +8,7 @@
 import subprocess
 import textwrap
 import time
-from typing import Callable
+from collections.abc import Callable
 
 
 class Command: