Merge branch 'master' into fix_match_callable

Author: randolf-scholz

.github/workflows/mypy_primer.yml

@@ -67,6 +67,7 @@ jobs:
             --debug \
             --additional-flags="--debug-serialize" \
             --output concise \
+            --mypy-install-librt \
             | tee diff_${{ matrix.shard-index }}.txt
           ) || [ $? -eq 1 ]
       - if: ${{ matrix.shard-index == 0 }}

CHANGELOG.md

@@ -2,9 +2,9 @@
 
 ## Next Release
 
-## Mypy 1.18
+## Mypy 1.18.1
 
-We’ve just uploaded mypy 1.18 to the Python Package Index ([PyPI](https://pypi.org/project/mypy/)).
+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
 improvements and bug fixes. You can install it as follows:
 
@@ -14,7 +14,7 @@ You can read the full documentation for this release on [Read the Docs](http://m
 
 ### Mypy Performance Improvements
 
-Mypy 1.18 includes numerous performance improvements, resulting in about 40% speedup
+Mypy 1.18.1 includes numerous performance improvements, resulting in about 40% speedup
 compared to 1.17 when type checking mypy itself. In extreme cases, the improvement
 can be 10x or higher. The list below is an overview of the various mypy optimizations.
 Many mypyc improvements (discussed in a separate section below) also improve performance.
@@ -283,6 +283,12 @@ Related PRs:
 
 Please see [git log](https://github.com/python/typeshed/commits/main?after=2480d7e7c74493a024eaf254c5d2c6f452c80ee2+0&branch=main&path=stdlib) for full list of standard library typeshed stub changes.
 
+### Mypy 1.18.2
+
+- Fix crash on recursive alias (Ivan Levkivskyi, PR [19845](https://github.com/python/mypy/pull/19845))
+- Add additional guidance for stubtest errors when runtime is `object.__init__` (Stephen Morton, PR [19733](https://github.com/python/mypy/pull/19733))
+- Fix handling of None values in f-string expressions in mypyc (BobTheBuidler, PR [19846](https://github.com/python/mypy/pull/19846))
+
 ### Acknowledgements
 
 Thanks to all mypy contributors who contributed to this release:

docs/source/command_line.rst

@@ -372,7 +372,7 @@ definitions or calls.
 
 .. option:: --untyped-calls-exclude
 
-    This flag allows to selectively disable :option:`--disallow-untyped-calls`
+    This flag allows one to selectively disable :option:`--disallow-untyped-calls`
     for functions and methods defined in specific packages, modules, or classes.
     Note that each exclude entry acts as a prefix. For example (assuming there
     are no type annotations for ``third_party_lib`` available):
@@ -562,7 +562,7 @@ potentially problematic or redundant in some way.
 
 .. option:: --deprecated-calls-exclude
 
-    This flag allows to selectively disable :ref:`deprecated<code-deprecated>` warnings
+    This flag allows one to selectively disable :ref:`deprecated<code-deprecated>` warnings
     for functions and methods defined in specific packages, modules, or classes.
     Note that each exclude entry acts as a prefix. For example (assuming ``foo.A.func`` is deprecated):
 
@@ -1255,12 +1255,18 @@ Miscellaneous
    stub packages were found, they are installed and then another run
    is performed.
 
-.. option:: --junit-xml JUNIT_XML
+.. option:: --junit-xml JUNIT_XML_OUTPUT_FILE
 
     Causes mypy to generate a JUnit XML test result document with
     type checking results. This can make it easier to integrate mypy
     with continuous integration (CI) tools.
 
+.. option:: --junit-format {global,per_file}
+
+    If --junit-xml is set, specifies format.
+    global (default): single test with all errors;
+    per_file: one test entry per file with failures.
+
 .. option:: --find-occurrences CLASS.MEMBER
 
     This flag will make mypy print out all usages of a class member

docs/source/common_issues.rst

@@ -731,7 +731,7 @@ This example demonstrates both safe and unsafe overrides:
 
     class NarrowerReturn(A):
         # A more specific return type is fine
-        def test(self, t: Sequence[int]) -> List[str]:  # OK
+        def test(self, t: Sequence[int]) -> list[str]:  # OK
             ...
 
     class GeneralizedReturn(A):
@@ -746,7 +746,7 @@ not necessary:
 .. code-block:: python
 
     class NarrowerArgument(A):
-        def test(self, t: List[int]) -> Sequence[str]:  # type: ignore[override]
+        def test(self, t: list[int]) -> Sequence[str]:  # type: ignore[override]
             ...
 
 .. _unreachable:

docs/source/config_file.rst

@@ -1153,6 +1153,15 @@ These options may only be set in the global section (``[mypy]``).
     type checking results. This can make it easier to integrate mypy
     with continuous integration (CI) tools.
 
+.. confval:: junit_format
+
+    :type: string
+    :default: ``global``
+
+    If junit_xml is set, specifies format.
+    global (default): single test with all errors;
+    per_file: one test entry per file with failures.
+
 .. confval:: scripts_are_modules
 
     :type: boolean

docs/source/error_code_list.rst

@@ -1032,8 +1032,8 @@ Warn about top level await expressions [top-level-await]
 This error code is separate from the general ``[syntax]`` errors, because in
 some environments (e.g. IPython) a top level ``await`` is allowed. In such
 environments a user may want to use ``--disable-error-code=top-level-await``,
-that allows to still have errors for other improper uses of ``await``, for
-example:
+which allows one to still have errors for other improper uses of ``await``,
+for example:
 
 .. code-block:: python
 

docs/source/error_code_list2.rst

@@ -676,3 +676,26 @@ Example:
                 print("red")
             case _:
                 print("other")
+
+.. _code-untyped-decorator:
+
+Error if an untyped decorator makes a typed function effectively untyped [untyped-decorator]
+--------------------------------------------------------------------------------------------
+
+If enabled with :option:`--disallow-untyped-decorators <mypy --disallow-untyped-decorators>`
+mypy generates an error if a typed function is wrapped by an untyped decorator
+(as this would effectively remove the benefits of typing the function).
+
+Example:
+
+.. code-block:: python
+
+        def printing_decorator(func):
+            def wrapper(*args, **kwds):
+                print("Calling", func)
+                return func(*args, **kwds)
+            return wrapper
+        # A decorated function.
+        @printing_decorator  # E: Untyped decorator makes function "add_forty_two" untyped  [untyped-decorator]
+        def add_forty_two(value: int) -> int:
+            return value + 42

docs/source/mypy_daemon.rst

@@ -252,16 +252,16 @@ command.
 Statically inspect expressions
 ******************************
 
-The daemon allows to get declared or inferred type of an expression (or other
+The daemon allows one to get the declared or inferred type of an expression (or other
 information about an expression, such as known attributes or definition location)
-using ``dmypy inspect LOCATION`` command. The location of the expression should be
+using the ``dmypy inspect LOCATION`` command. The location of the expression should be
 specified in the format ``path/to/file.py:line:column[:end_line:end_column]``.
 Both line and column are 1-based. Both start and end position are inclusive.
 These rules match how mypy prints the error location in error messages.
 
 If a span is given (i.e. all 4 numbers), then only an exactly matching expression
 is inspected. If only a position is given (i.e. 2 numbers, line and column), mypy
-will inspect all *expressions*, that include this position, starting from the
+will inspect all expressions that include this position, starting from the
 innermost one.
 
 Consider this Python code snippet:

docs/source/stubtest.rst

@@ -99,8 +99,75 @@ to mypy build errors". In this case, you will need to mitigate those errors
 before stubtest will run. Despite potential overlap in errors here, stubtest is
 not intended as a substitute for running mypy directly.
 
+Allowlist
+*********
+
 If you wish to ignore some of stubtest's complaints, stubtest supports a
-pretty handy allowlist system.
+pretty handy :option:`--allowlist` system.
+
+Let's say that you have this python module called ``ex``:
+
+.. code-block:: python
+
+   try:
+       import optional_expensive_dep
+   except ImportError:
+       optional_expensive_dep = None
+
+   first = 1
+   if optional_expensive_dep:
+       second = 2
+
+Let's say that you can't install ``optional_expensive_dep`` in CI for some reason,
+but you still want to include ``second: int`` in the stub file:
+
+.. code-block:: python
+
+    first: int
+    second: int
+
+In this case stubtest will correctly complain:
+
+.. code-block:: shell
+
+   error: ex.second is not present at runtime
+   Stub: in file /.../ex.pyi:2
+   builtins.int
+   Runtime:
+   MISSING
+
+   Found 1 error (checked 1 module)
+
+To fix this, you can add an ``allowlist`` entry:
+
+.. code-block:: ini
+
+   # Allowlist entries in `allowlist.txt` file:
+
+   # Does not exist if `optional_expensive_dep` is not installed:
+   ex.second
+
+And now when running stubtest with ``--allowlist=allowlist.txt``,
+no errors will be generated anymore.
+
+Allowlists also support regular expressions,
+which can be useful to ignore many similar errors at once.
+They can also be useful for suppressing stubtest errors that occur sometimes,
+but not on every CI run. For example, if some CI workers have
+``optional_expensive_dep`` installed, stubtest might complain with this message
+on those workers if you had the ``ex.second`` allowlist entry:
+
+.. code-block:: ini
+
+   note: unused allowlist entry ex.second
+   Found 1 error (checked 1 module)
+
+Changing ``ex.second`` to be ``(ex\.second)?`` will make this error optional,
+meaning that stubtest will pass whether or not a CI runner
+has``optional_expensive_dep`` installed.
+
+CLI
+***
 
 The rest of this section documents the command line interface of stubtest.
 
@@ -119,15 +186,15 @@ The rest of this section documents the command line interface of stubtest.
 .. option:: --allowlist FILE
 
     Use file as an allowlist. Can be passed multiple times to combine multiple
-    allowlists. Allowlists can be created with --generate-allowlist. Allowlists
-    support regular expressions.
+    allowlists. Allowlists can be created with :option:`--generate-allowlist`.
+    Allowlists support regular expressions.
 
     The presence of an entry in the allowlist means stubtest will not generate
     any errors for the corresponding definition.
 
 .. option:: --generate-allowlist
 
-    Print an allowlist (to stdout) to be used with --allowlist
+    Print an allowlist (to stdout) to be used with :option:`--allowlist`.
 
     When introducing stubtest to an existing project, this is an easy way to
     silence all existing errors.
@@ -141,17 +208,17 @@ The rest of this section documents the command line interface of stubtest.
 
     Note if an allowlist entry is a regex that matches the empty string,
     stubtest will never consider it unused. For example, to get
-    `--ignore-unused-allowlist` behaviour for a single allowlist entry like
+    ``--ignore-unused-allowlist`` behaviour for a single allowlist entry like
     ``foo.bar`` you could add an allowlist entry ``(foo\.bar)?``.
     This can be useful when an error only occurs on a specific platform.
 
 .. option:: --mypy-config-file FILE
 
-    Use specified mypy config file to determine mypy plugins and mypy path
+    Use specified mypy config *file* to determine mypy plugins and mypy path
 
 .. option:: --custom-typeshed-dir DIR
 
-    Use the custom typeshed in DIR
+    Use the custom typeshed in *DIR*
 
 .. option:: --check-typeshed
 

misc/analyze_cache.py

@@ -41,7 +41,7 @@ def extract(chunks: Iterable[JsonDict]) -> Iterable[JsonDict]:
             if isinstance(chunk, dict):
                 yield chunk
                 yield from extract(chunk.values())
-            elif isinstance(chunk, list):
+            elif isinstance(chunk, list):  # type: ignore[unreachable] #TODO: is this actually unreachable, or are our types wrong?
                 yield from extract(chunk)
 
     yield from extract([chunk.data for chunk in chunks])
@@ -93,7 +93,7 @@ def compress(chunk: JsonDict) -> JsonDict:
     def helper(chunk: JsonDict) -> JsonDict:
         nonlocal counter
         if not isinstance(chunk, dict):
-            return chunk
+            return chunk  # type: ignore[unreachable] #TODO: is this actually unreachable, or are our types wrong?
 
         if len(chunk) <= 2:
             return chunk
@@ -124,7 +124,7 @@ def decompress(chunk: JsonDict) -> JsonDict:
 
     def helper(chunk: JsonDict) -> JsonDict:
         if not isinstance(chunk, dict):
-            return chunk
+            return chunk  # type: ignore[unreachable] #TODO: is this actually unreachable, or are our types wrong?
         if ".id" in chunk:
             return cache[chunk[".id"]]