Close #9664: autodoc: autodoc-process-bases supports reST snippet

This allows to inject a reST snippet through autodoc-process-bases
event.  It helps to modify the base classes of any class to the expected
mark-up'ed text by custom extension.

1 files changed, 2 insertions, 0 deletions

diff --git a/sphinx/util/typing.py b/sphinx/util/typing.py
index 7380f4783..87707d48f 100644
--- a/sphinx/util/typing.py
+++ b/sphinx/util/typing.py
@@ -113,6 +113,8 @@ def restify(cls: Optional[Type]) -> str:
             return ':py:obj:`None`'
         elif cls is Ellipsis:
             return '...'
+        elif isinstance(cls, str):
+            return cls
         elif cls in INVALID_BUILTIN_CLASSES:
             return ':py:class:`%s`' % INVALID_BUILTIN_CLASSES[cls]
         elif inspect.isNewType(cls):