Merge branch 'master' into master

.github/workflows/test.yml

@@ -70,14 +70,14 @@ jobs:
           toxenv: py
           tox_extra_args: "-n 4"
           test_mypyc: true
-
         - name: Test suite with py313-ubuntu, mypyc-compiled
           python: '3.13'
           arch: x64
           os: ubuntu-latest
           toxenv: py
           tox_extra_args: "-n 4"
           test_mypyc: true
+
         # - name: Test suite with py314-dev-ubuntu
         #   python: '3.14-dev'
         #   arch: x64
@@ -94,13 +94,16 @@ jobs:
           os: macos-13
           toxenv: py
           tox_extra_args: "-n 3 mypyc/test/test_run.py mypyc/test/test_external.py"
-        - name: mypyc runtime tests with py38-debug-build-ubuntu
-          python: '3.8.17'
-          arch: x64
-          os: ubuntu-latest
-          toxenv: py
-          tox_extra_args: "-n 4 mypyc/test/test_run.py mypyc/test/test_external.py"
-          debug_build: true
+        # This is broken. See
+        # - https://github.com/python/mypy/issues/17819
+        # - https://github.com/python/mypy/pull/17822
+        # - name: mypyc runtime tests with py38-debug-build-ubuntu
+        #   python: '3.8.17'
+        #   arch: x64
+        #   os: ubuntu-latest
+        #   toxenv: py
+        #   tox_extra_args: "-n 4 mypyc/test/test_run.py mypyc/test/test_external.py"
+        #   debug_build: true
 
         - name: Type check our own code (py38-ubuntu)
           python: '3.8'
@@ -148,17 +151,17 @@ jobs:
         ./misc/build-debug-python.sh $PYTHONVERSION $PYTHONDIR $VENV
         # TODO: does this do anything? env vars aren't passed to the next step right
         source $VENV/bin/activate
-    - name: Latest Dev build
+    - name: Latest dev build
       if: ${{ endsWith(matrix.python, '-dev') }}
       run: |
-          sudo apt-get update
-          sudo apt-get install -y --no-install-recommends \
-            build-essential gdb lcov libbz2-dev libffi-dev libgdbm-dev liblzma-dev libncurses5-dev \
-            libreadline6-dev libsqlite3-dev libssl-dev lzma lzma-dev tk-dev uuid-dev zlib1g-dev
           git clone --depth 1 https://github.com/python/cpython.git /tmp/cpython --branch $( echo ${{ matrix.python }} | sed 's/-dev//' )
           cd /tmp/cpython
           echo git rev-parse HEAD; git rev-parse HEAD
           git show --no-patch
+          sudo apt-get update
+          sudo apt-get install -y --no-install-recommends \
+            build-essential gdb lcov libbz2-dev libffi-dev libgdbm-dev liblzma-dev libncurses5-dev \
+            libreadline6-dev libsqlite3-dev libssl-dev lzma lzma-dev tk-dev uuid-dev zlib1g-dev
           ./configure --prefix=/opt/pythondev
           make -j$(nproc)
           sudo make install
@@ -190,7 +193,7 @@ jobs:
 
     - name: Setup tox environment
       run: |
-        tox run -e ${{ matrix.toxenv }} --notes
+        tox run -e ${{ matrix.toxenv }} --notest
     - name: Test
       run: tox run -e ${{ matrix.toxenv }} --skip-pkg-install -- ${{ matrix.tox_extra_args }}
       continue-on-error: ${{ matrix.allow_failure == 'true' }}

CHANGELOG.md

@@ -187,6 +187,8 @@ List of documentation updates:
  * Make changelog visible in mypy documentation (quinn-sasha, PR [17742](https://github.com/python/mypy/pull/17742))
  * List all incomplete features in `--enable-incomplete-feature` docs (sobolevn, PR [17633](https://github.com/python/mypy/pull/17633))
  * Remove the explicit setting of a pygments theme (Pradyun Gedam, PR [17571](https://github.com/python/mypy/pull/17571))
+ * Document ReadOnly with TypedDict (Jukka Lehtosalo, PR [17905](https://github.com/python/mypy/pull/17905))
+ * Document TypeIs (Chelsea Durazo, PR [17821](https://github.com/python/mypy/pull/17821))
 
 ### Experimental Inline TypedDict Syntax
 
@@ -250,6 +252,9 @@ This feature was contributed by Ivan Levkivskyi (PR [17457](https://github.com/p
  * Fix typechecking for async generators (Danny Yang, PR [17452](https://github.com/python/mypy/pull/17452))
  * Fix strict optional handling in attrs plugin (Ivan Levkivskyi, PR [17451](https://github.com/python/mypy/pull/17451))
  * Allow mixing ParamSpec and TypeVarTuple in Generic (Ivan Levkivskyi, PR [17450](https://github.com/python/mypy/pull/17450))
+ * Improvements to `functools.partial` of types (Shantanu, PR [17898](https://github.com/python/mypy/pull/17898))
+ * Make ReadOnly TypedDict items covariant (Jukka Lehtosalo, PR [17904](https://github.com/python/mypy/pull/17904))
+ * Fix union callees with `functools.partial` (Jukka Lehtosalo, PR [17903](https://github.com/python/mypy/pull/17903))
 
 ### Typeshed Updates
 
@@ -263,6 +268,7 @@ Thanks to all mypy contributors who contributed to this release:
 - Bénédikt Tran
 - Brian Schubert
 - bzoracler
+- Chelsea Durazo
 - Danny Yang
 - Edgar Ramírez Mondragón
 - Eric Mark Martin

mypy/main.py

@@ -22,7 +22,14 @@
 from mypy.errors import CompileError
 from mypy.find_sources import InvalidSourceList, create_source_list
 from mypy.fscache import FileSystemCache
-from mypy.modulefinder import BuildSource, FindModuleCache, SearchPaths, get_search_dirs, mypy_path
+from mypy.modulefinder import (
+    BuildSource,
+    FindModuleCache,
+    ModuleNotFoundReason,
+    SearchPaths,
+    get_search_dirs,
+    mypy_path,
+)
 from mypy.options import INCOMPLETE_FEATURES, BuildType, Options
 from mypy.split_namespace import SplitNamespace
 from mypy.version import __version__
@@ -1413,7 +1420,15 @@ def set_strict_flags() -> None:
                 fail(f"Package name '{p}' cannot have a slash in it.", stderr, options)
             p_targets = cache.find_modules_recursive(p)
             if not p_targets:
-                fail(f"Can't find package '{p}'", stderr, options)
+                reason = cache.find_module(p)
+                if reason is ModuleNotFoundReason.FOUND_WITHOUT_TYPE_HINTS:
+                    fail(
+                        f"Package '{p}' cannot be type checked due to missing py.typed marker. See https://mypy.readthedocs.io/en/stable/installed_packages.html for more details",
+                        stderr,
+                        options,
+                    )
+                else:
+                    fail(f"Can't find package '{p}'", stderr, options)
             targets.extend(p_targets)
         for m in special_opts.modules:
             targets.append(BuildSource(None, m, None))

mypy/plugins/functools.py

@@ -18,6 +18,7 @@
     Type,
     TypeOfAny,
     UnboundType,
+    UnionType,
     get_proper_type,
 )
 
@@ -130,7 +131,19 @@ def partial_new_callback(ctx: mypy.plugin.FunctionContext) -> Type:
     if isinstance(get_proper_type(ctx.arg_types[0][0]), Overloaded):
         # TODO: handle overloads, just fall back to whatever the non-plugin code does
         return ctx.default_return_type
-    fn_type = ctx.api.extract_callable_type(ctx.arg_types[0][0], ctx=ctx.default_return_type)
+    return handle_partial_with_callee(ctx, callee=ctx.arg_types[0][0])
+
+
+def handle_partial_with_callee(ctx: mypy.plugin.FunctionContext, callee: Type) -> Type:
+    if not isinstance(ctx.api, mypy.checker.TypeChecker):  # use internals
+        return ctx.default_return_type
+
+    if isinstance(callee_proper := get_proper_type(callee), UnionType):
+        return UnionType.make_union(
+            [handle_partial_with_callee(ctx, item) for item in callee_proper.items]
+        )
+
+    fn_type = ctx.api.extract_callable_type(callee, ctx=ctx.default_return_type)
     if fn_type is None:
         return ctx.default_return_type
 

test-data/unit/check-functools.test

@@ -346,15 +346,32 @@ fn1: Union[Callable[[int], int], Callable[[int], int]]
 reveal_type(functools.partial(fn1, 2)())  # N: Revealed type is "builtins.int"
 
 fn2: Union[Callable[[int], int], Callable[[int], str]]
-reveal_type(functools.partial(fn2, 2)())  # N: Revealed type is "builtins.object"
+reveal_type(functools.partial(fn2, 2)())  # N: Revealed type is "Union[builtins.int, builtins.str]"
 
 fn3: Union[Callable[[int], int], str]
 reveal_type(functools.partial(fn3, 2)())  # E: "str" not callable \
-                                          # E: "Union[Callable[[int], int], str]" not callable \
                                           # N: Revealed type is "builtins.int" \
                                           # E: Argument 1 to "partial" has incompatible type "Union[Callable[[int], int], str]"; expected "Callable[..., int]"
 [builtins fixtures/tuple.pyi]
 
+[case testFunctoolsPartialUnionOfTypeAndCallable]
+import functools
+from typing import Callable, Union, Type
+from typing_extensions import TypeAlias
+
+class FooBar:
+    def __init__(self, arg1: str) -> None:
+        pass
+
+def f1(t: Union[Type[FooBar], Callable[..., 'FooBar']]) -> None:
+    val = functools.partial(t)
+
+FooBarFunc: TypeAlias = Callable[..., 'FooBar']
+
+def f2(t: Union[Type[FooBar], FooBarFunc]) -> None:
+    val = functools.partial(t)
+[builtins fixtures/tuple.pyi]
+
 [case testFunctoolsPartialExplicitType]
 from functools import partial
 from typing import Type, TypeVar, Callable