autodoc: Add a helper that checks the object is mocked; ismock()

sphinx/ext/autodoc/mock.py

@@ -17,6 +17,7 @@
 from typing import Any, Generator, Iterator, List, Sequence, Tuple, Union
 
 from sphinx.util import logging
+from sphinx.util.inspect import safe_getattr
 
 logger = logging.getLogger(__name__)
 
@@ -147,3 +148,24 @@ def mock(modnames: List[str]) -> Generator[None, None, None]:
     finally:
         sys.meta_path.remove(finder)
         finder.invalidate_caches()
+
+
+def ismock(subject: Any) -> bool:
+    """Check if the object is mocked."""
+    # check the object has '__sphinx_mock__' attribute
+    if not hasattr(subject, '__sphinx_mock__'):
+        return False
+
+    # check the object is mocked module
+    if isinstance(subject, _MockModule):
+        return True
+
+    try:
+        # check the object is mocked object
+        __mro__ = safe_getattr(type(subject), '__mro__', [])
+        if len(__mro__) > 2 and __mro__[1] is _MockObject:
+            return True
+    except AttributeError:
+        pass
+
+    return False

tests/test_ext_autodoc_mock.py

@@ -15,7 +15,7 @@
 
 import pytest
 
-from sphinx.ext.autodoc.mock import _MockModule, _MockObject, mock
+from sphinx.ext.autodoc.mock import _MockModule, _MockObject, ismock, mock
 
 
 def test_MockModule():
@@ -129,3 +129,19 @@ class Bar:
     assert func.__doc__ == "docstring"
     assert Foo.meth.__doc__ == "docstring"
     assert Bar.__doc__ == "docstring"
+
+
+def test_ismock():
+    with mock(['sphinx.unknown']):
+        mod1 = import_module('sphinx.unknown')
+        mod2 = import_module('sphinx.application')
+
+        class Inherited(mod1.Class):
+            pass
+
+        assert ismock(mod1) is True
+        assert ismock(mod1.Class) is True
+        assert ismock(Inherited) is False
+
+        assert ismock(mod2) is False
+        assert ismock(mod2.Sphinx) is False