Fix type guard handling for classes (#365)

Author: gaborbernat

src/sphinx_autodoc_typehints/__init__.py

@@ -404,29 +404,32 @@ def get_all_type_hints(autodoc_mock_imports: list[str], obj: Any, name: str) ->
 _TYPE_GUARD_IMPORTS_RESOLVED_GLOBALS_ID = set()
 
 
-def _resolve_type_guarded_imports(autodoc_mock_imports: list[str], obj: Any) -> None:
-    if (hasattr(obj, "__module__") and obj.__module__ not in _TYPE_GUARD_IMPORTS_RESOLVED) or (
-        hasattr(obj, "__globals__") and id(obj.__globals__) not in _TYPE_GUARD_IMPORTS_RESOLVED_GLOBALS_ID
-    ):
-        _TYPE_GUARD_IMPORTS_RESOLVED.add(obj.__module__)
-        if obj.__module__ not in sys.builtin_module_names:
-            if hasattr(obj, "__globals__"):
-                _TYPE_GUARD_IMPORTS_RESOLVED_GLOBALS_ID.add(id(obj.__globals__))
-
-            module = inspect.getmodule(obj)
-            if module:
-                try:
-                    module_code = inspect.getsource(module)
-                except (TypeError, OSError):
-                    ...  # no source code => no type guards
-                else:
-                    for _, part in _TYPE_GUARD_IMPORT_RE.findall(module_code):
-                        guarded_code = textwrap.dedent(part)
-                        try:
-                            with mock(autodoc_mock_imports):
-                                exec(guarded_code, obj.__globals__)  # noqa: S102
-                        except Exception as exc:  # noqa: BLE001
-                            _LOGGER.warning(f"Failed guarded type import with {exc!r}")
+def _resolve_type_guarded_imports(autodoc_mock_imports: list[str], obj: Any) -> None:  # noqa: C901
+    if hasattr(obj, "__module__") and obj.__module__ in _TYPE_GUARD_IMPORTS_RESOLVED:
+        return  # already processed module
+    if not hasattr(obj, "__globals__"):  # classes with __slots__ do not have this
+        return  # if lacks globals nothing we can do
+    if id(obj.__globals__) in _TYPE_GUARD_IMPORTS_RESOLVED_GLOBALS_ID:
+        return  # already processed object
+    _TYPE_GUARD_IMPORTS_RESOLVED.add(obj.__module__)
+    if obj.__module__ not in sys.builtin_module_names:
+        if hasattr(obj, "__globals__"):
+            _TYPE_GUARD_IMPORTS_RESOLVED_GLOBALS_ID.add(id(obj.__globals__))
+
+        module = inspect.getmodule(obj)
+        if module:
+            try:
+                module_code = inspect.getsource(module)
+            except (TypeError, OSError):
+                ...  # no source code => no type guards
+            else:
+                for _, part in _TYPE_GUARD_IMPORT_RE.findall(module_code):
+                    guarded_code = textwrap.dedent(part)
+                    try:
+                        with mock(autodoc_mock_imports):
+                            exec(guarded_code, obj.__globals__)  # noqa: S102
+                    except Exception as exc:  # noqa: BLE001
+                        _LOGGER.warning(f"Failed guarded type import with {exc!r}")
 
 
 def _get_type_hint(autodoc_mock_imports: list[str], name: str, obj: Any) -> dict[str, Any]:

tests/roots/test-resolve-typing-guard/demo_typing_guard.py

@@ -6,11 +6,12 @@
 from functools import cmp_to_key  # has __module__ but cannot get module as is builtin
 from typing import TYPE_CHECKING
 
+from demo_typing_guard_dummy import AnotherClass
+
 if TYPE_CHECKING:
     from decimal import Decimal
     from typing import Sequence
 
-    from demo_typing_guard_dummy import AnotherClass  # module contains mocked import # noqa: F401
 
 if typing.TYPE_CHECKING:
     from typing import AnyStr
@@ -34,14 +35,27 @@ def a(f: Decimal, s: AnyStr) -> Sequence[AnyStr | Decimal]:
 class SomeClass:
     """This class do something."""
 
+    def create(self, item: Decimal) -> None:
+        """
+        Create something.
+
+        :param item: the item in question
+        """
+
     if TYPE_CHECKING:  # Classes doesn't have `__globals__` attribute
 
-        def __getattr__(self, item: str):  # noqa: ANN204
-            """This method do something."""
+        def guarded(self, item: Decimal) -> None:
+            """
+            Guarded method.
+
+            :param item: some item
+            """
 
 
 __all__ = [
     "a",
     "ValueError",
     "cmp_to_key",
+    "SomeClass",
+    "AnotherClass",
 ]

tests/roots/test-resolve-typing-guard/demo_typing_guard_dummy.py

@@ -4,4 +4,4 @@
 
 
 class AnotherClass:
-    ...
+    """Another class is here"""

tests/test_sphinx_autodoc_typehints.py

@@ -764,7 +764,8 @@ def test_resolve_typing_guard_imports(app: SphinxTestApp, status: StringIO, warn
     set_python_path()
     app.config.autodoc_mock_imports = ["viktor"]  # type: ignore[attr-defined] # create flag
     app.build()
-    assert "build succeeded" in status.getvalue()
+    out = status.getvalue()
+    assert "build succeeded" in out
     err = warning.getvalue()
     r = re.compile("WARNING: Failed guarded type import")
     assert len(r.findall(err)) == 1