Fix #9175: autodoc: Special member is not documented in the module

The special members are not treated as "attributes".  So they're not
handled by DataDocumenter.  This moves the detection to the earlier
step of filter_members().

CHANGES

@@ -23,6 +23,7 @@ Features added
 * #8588: autodoc: :confval:`autodoc_type_aliases` now supports dotted name. It
   allows you to define an alias for a class with module name like
   ``foo.bar.BazClass``
+* #9175: autodoc: Special member is not documented in the module
 * #3257: autosummary: Support instance attributes for classes
 * #9129: html search: Show search summaries when html_copy_source = False
 * #9120: html theme: Eliminate prompt characters of code-block from copyable

sphinx/ext/autodoc/__init__.py

@@ -709,6 +709,8 @@ class Documenter:
             # if isattr is True, the member is documented as an attribute
             if member is INSTANCEATTR:
                 isattr = True
+            elif (namespace, membername) in attr_docs:
+                isattr = True
             else:
                 isattr = False
 
@@ -769,7 +771,6 @@ class Documenter:
                 else:
                     # keep documented attributes
                     keep = True
-                isattr = True
             elif want_all and isprivate:
                 if has_doc or self.options.undoc_members:
                     if self.options.private_members is None:

tests/roots/test-ext-autodoc/target/module.py

@@ -0,0 +1,14 @@
+undocumented = 1
+
+#: docstring
+documented = 1
+
+undoc_annotated: int
+
+#: docstring
+annotated: int
+
+__special__ = 1
+
+#: docstring
+__documented_special__ = 1

tests/test_ext_autodoc_automodule.py

@@ -29,6 +29,95 @@ def test_empty_all(app):
     ]
 
 
+@pytest.mark.sphinx('html', testroot='ext-autodoc')
+def test_automodule(app):
+    options = {'members': None}
+    actual = do_autodoc(app, 'module', 'target.module', options)
+    assert list(actual) == [
+        '',
+        '.. py:module:: target.module',
+        '',
+        '',
+        '.. py:data:: annotated',
+        '   :module: target.module',
+        '   :type: int',
+        '',
+        '   docstring',
+        '',
+        '',
+        '.. py:data:: documented',
+        '   :module: target.module',
+        '   :value: 1',
+        '',
+        '   docstring',
+        '',
+    ]
+
+
+@pytest.mark.sphinx('html', testroot='ext-autodoc')
+def test_automodule_undoc_members(app):
+    options = {'members': None,
+               'undoc-members': None}
+    actual = do_autodoc(app, 'module', 'target.module', options)
+    assert list(actual) == [
+        '',
+        '.. py:module:: target.module',
+        '',
+        '',
+        '.. py:data:: annotated',
+        '   :module: target.module',
+        '   :type: int',
+        '',
+        '   docstring',
+        '',
+        '',
+        '.. py:data:: documented',
+        '   :module: target.module',
+        '   :value: 1',
+        '',
+        '   docstring',
+        '',
+        '',
+        '.. py:data:: undoc_annotated',
+        '   :module: target.module',
+        '   :type: int',
+        '',
+    ]
+
+
+@pytest.mark.sphinx('html', testroot='ext-autodoc')
+def test_automodule_special_members(app):
+    options = {'members': None,
+               'special-members': None}
+    actual = do_autodoc(app, 'module', 'target.module', options)
+    assert list(actual) == [
+        '',
+        '.. py:module:: target.module',
+        '',
+        '',
+        '.. py:data:: __documented_special__',
+        '   :module: target.module',
+        '   :value: 1',
+        '',
+        '   docstring',
+        '',
+        '',
+        '.. py:data:: annotated',
+        '   :module: target.module',
+        '   :type: int',
+        '',
+        '   docstring',
+        '',
+        '',
+        '.. py:data:: documented',
+        '   :module: target.module',
+        '   :value: 1',
+        '',
+        '   docstring',
+        '',
+    ]
+
+
 @pytest.mark.sphinx('html', testroot='ext-autodoc',
                     confoverrides={'autodoc_mock_imports': ['missing_module',
                                                             'missing_package1',