diff --git a/mypy/stubtest.py b/mypy/stubtest.py index 378f61471437..31053f120931 100644 --- a/mypy/stubtest.py +++ b/mypy/stubtest.py @@ -349,17 +349,9 @@ def _belongs_to_runtime(r: types.ModuleType, attr: str) -> bool: yield from verify(stub_entry, runtime_entry, object_path + [entry]) -@verify.register(nodes.TypeInfo) -def verify_typeinfo( - stub: nodes.TypeInfo, runtime: MaybeMissing[type[Any]], object_path: list[str] +def _verify_final( + stub: nodes.TypeInfo, runtime: type[Any], object_path: list[str] ) -> Iterator[Error]: - if isinstance(runtime, Missing): - yield Error(object_path, "is not present at runtime", stub, runtime, stub_desc=repr(stub)) - return - if not isinstance(runtime, type): - yield Error(object_path, "is not a type", stub, runtime, stub_desc=repr(stub)) - return - try: class SubClass(runtime): # type: ignore @@ -380,6 +372,59 @@ class SubClass(runtime): # type: ignore # Examples: ctypes.Array, ctypes._SimpleCData pass + +def _verify_metaclass( + stub: nodes.TypeInfo, runtime: type[Any], object_path: list[str] +) -> Iterator[Error]: + # We exclude protocols, because of how complex their implementation is in different versions of + # python. Enums are also hard, ignoring. + # TODO: check that metaclasses are identical? + if not stub.is_protocol and not stub.is_enum: + runtime_metaclass = type(runtime) + if runtime_metaclass is not type and stub.metaclass_type is None: + # This means that runtime has a custom metaclass, but a stub does not. + yield Error( + object_path, + "is inconsistent, metaclass differs", + stub, + runtime, + stub_desc="N/A", + runtime_desc=f"{runtime_metaclass}", + ) + elif ( + runtime_metaclass is type + and stub.metaclass_type is not None + # We ignore extra `ABCMeta` metaclass on stubs, this might be typing hack. + # We also ignore `builtins.type` metaclass as an implementation detail in mypy. + and not mypy.types.is_named_instance( + stub.metaclass_type, ("abc.ABCMeta", "builtins.type") + ) + ): + # This means that our stub has a metaclass that is not present at runtime. + yield Error( + object_path, + "metaclass mismatch", + stub, + runtime, + stub_desc=f"{stub.metaclass_type.type.fullname}", + runtime_desc="N/A", + ) + + +@verify.register(nodes.TypeInfo) +def verify_typeinfo( + stub: nodes.TypeInfo, runtime: MaybeMissing[type[Any]], object_path: list[str] +) -> Iterator[Error]: + if isinstance(runtime, Missing): + yield Error(object_path, "is not present at runtime", stub, runtime, stub_desc=repr(stub)) + return + if not isinstance(runtime, type): + yield Error(object_path, "is not a type", stub, runtime, stub_desc=repr(stub)) + return + + yield from _verify_final(stub, runtime, object_path) + yield from _verify_metaclass(stub, runtime, object_path) + # Check everything already defined on the stub class itself (i.e. not inherited) to_check = set(stub.names) # Check all public things on the runtime class diff --git a/mypy/test/teststubtest.py b/mypy/test/teststubtest.py index f15650811dc5..8e78966363d4 100644 --- a/mypy/test/teststubtest.py +++ b/mypy/test/teststubtest.py @@ -1271,6 +1271,69 @@ def test_type_var(self) -> Iterator[Case]: ) yield Case(stub="C = ParamSpec('C')", runtime="C = ParamSpec('C')", error=None) + @collect_cases + def test_metaclass_match(self) -> Iterator[Case]: + yield Case(stub="class Meta(type): ...", runtime="class Meta(type): ...", error=None) + yield Case(stub="class A0: ...", runtime="class A0: ...", error=None) + yield Case( + stub="class A1(metaclass=Meta): ...", + runtime="class A1(metaclass=Meta): ...", + error=None, + ) + yield Case(stub="class A2: ...", runtime="class A2(metaclass=Meta): ...", error="A2") + yield Case(stub="class A3(metaclass=Meta): ...", runtime="class A3: ...", error="A3") + + # Explicit `type` metaclass can always be added in any part: + yield Case( + stub="class T1(metaclass=type): ...", + runtime="class T1(metaclass=type): ...", + error=None, + ) + yield Case(stub="class T2: ...", runtime="class T2(metaclass=type): ...", error=None) + yield Case(stub="class T3(metaclass=type): ...", runtime="class T3: ...", error=None) + + # Explicit check that `_protected` names are also supported: + yield Case(stub="class _P1(type): ...", runtime="class _P1(type): ...", error=None) + yield Case(stub="class P2: ...", runtime="class P2(metaclass=_P1): ...", error="P2") + + # With inheritance: + yield Case( + stub=""" + class I1(metaclass=Meta): ... + class S1(I1): ... + """, + runtime=""" + class I1(metaclass=Meta): ... + class S1(I1): ... + """, + error=None, + ) + yield Case( + stub=""" + class I2(metaclass=Meta): ... + class S2: ... # missing inheritance + """, + runtime=""" + class I2(metaclass=Meta): ... + class S2(I2): ... + """, + error="S2", + ) + + @collect_cases + def test_metaclass_abcmeta(self) -> Iterator[Case]: + # Handling abstract metaclasses is special: + yield Case(stub="from abc import ABCMeta", runtime="from abc import ABCMeta", error=None) + yield Case( + stub="class A1(metaclass=ABCMeta): ...", + runtime="class A1(metaclass=ABCMeta): ...", + error=None, + ) + # Stubs cannot miss abstract metaclass: + yield Case(stub="class A2: ...", runtime="class A2(metaclass=ABCMeta): ...", error="A2") + # But, stubs can add extra abstract metaclass, this might be a typing hack: + yield Case(stub="class A3(metaclass=ABCMeta): ...", runtime="class A3: ...", error=None) + @collect_cases def test_abstract_methods(self) -> Iterator[Case]: yield Case(