deprecate PyClassmember class

CHANGES

@@ -33,6 +33,7 @@ Deprecated
 * ``sphinx.directives.TabularColumns``
 * ``sphinx.directives.TocTree``
 * ``sphinx.directives.VersionChange``
+* ``sphinx.domains.python.PyClassmember``
 * ``sphinx.domains.std.StandardDomain._resolve_citation_xref()``
 * ``sphinx.domains.std.StandardDomain.note_citations()``
 * ``sphinx.domains.std.StandardDomain.note_citation_refs()``

doc/extdev/deprecated.rst

@@ -116,6 +116,14 @@ The following is a list of deprecated interfaces.
      - 4.0
      - ``sphinx.directives.other.VersionChange``
 
+   * - ``sphinx.domains.python.PyClassmember``
+     - 2.1
+     - 4.0
+     - ``sphinx.domains.python.PyAttribute``,
+       ``sphinx.domains.python.PyMethod``,
+       ``sphinx.domains.python.PyClassMethod`` and
+       ``sphinx.domains.python.PyStaticMethod``
+
    * - ``sphinx.domains.std.StandardDomain._resolve_citation_xref()``
      - 2.1
      - 4.0

sphinx/domains/python.py

@@ -9,13 +9,16 @@
 """
 
 import re
+import warnings
 from typing import cast
 
 from docutils import nodes
 from docutils.parsers.rst import directives
 
 from sphinx import addnodes, locale
-from sphinx.deprecation import DeprecatedDict, RemovedInSphinx30Warning
+from sphinx.deprecation import (
+    DeprecatedDict, RemovedInSphinx30Warning, RemovedInSphinx40Warning
+)
 from sphinx.directives import ObjectDescription
 from sphinx.domains import Domain, ObjType, Index, IndexEntry
 from sphinx.locale import _, __
@@ -453,6 +456,13 @@ class PyClassmember(PyObject):
     Description of a class member (methods, attributes).
     """
 
+    def run(self):
+        # type: () -> List[nodes.Node]
+        warnings.warn('PyClassmember is deprecated.',
+                      RemovedInSphinx40Warning)
+
+        return super().run()
+
     def needs_arglist(self):
         # type: () -> bool
         return self.objtype.endswith('method')