From 80f84260bad23b0f71b86636a987a2b9dd49b828 Mon Sep 17 00:00:00 2001
From: Takeshi KOMIYA <i.tkomiya@gmail.com>
Date: Mon, 22 Nov 2021 01:48:47 +0900
Subject: [PATCH] Fix #9879: autodoc: AttributeError for object having invalid
 __doc__

---
 CHANGES                        |  2 ++
 sphinx/ext/autodoc/__init__.py |  2 +-
 sphinx/util/inspect.py         | 11 +++++++++--
 3 files changed, 12 insertions(+), 3 deletions(-)

diff --git a/CHANGES b/CHANGES
index 4ee8d55cd91..ec3d22b267b 100644
--- a/CHANGES
+++ b/CHANGES
@@ -18,6 +18,8 @@ Bugs fixed
 
 * #9838: autodoc: AttributeError is raised on building document for functions
   decorated by functools.lru_cache
+* #9879: autodoc: AttributeError is raised on building document for an object
+  having invalid __doc__ atribute
 
 Testing
 --------
diff --git a/sphinx/ext/autodoc/__init__.py b/sphinx/ext/autodoc/__init__.py
index 2cdf224cb25..8fcefcc716e 100644
--- a/sphinx/ext/autodoc/__init__.py
+++ b/sphinx/ext/autodoc/__init__.py
@@ -1704,7 +1704,7 @@ def get_doc(self, ignore: int = None) -> Optional[List[List[str]]]:
         classdoc_from = self.options.get('class-doc-from', self.config.autoclass_content)
 
         docstrings = []
-        attrdocstring = self.get_attr(self.object, '__doc__', None)
+        attrdocstring = getdoc(self.object, self.get_attr)
         if attrdocstring:
             docstrings.append(attrdocstring)
 
diff --git a/sphinx/util/inspect.py b/sphinx/util/inspect.py
index 3a39bde1d6b..24ea49ae04e 100644
--- a/sphinx/util/inspect.py
+++ b/sphinx/util/inspect.py
@@ -871,6 +871,13 @@ def getdoc(obj: Any, attrgetter: Callable = safe_getattr,
     * inherited docstring
     * inherited decorated methods
     """
+    def getdoc_internal(obj: Any, attrgetter: Callable = safe_getattr) -> Optional[str]:
+        doc = attrgetter(obj, '__doc__', None)
+        if isinstance(doc, str):
+            return doc
+        else:
+            return None
+
     if cls and name and isclassmethod(obj, cls, name):
         for basecls in getmro(cls):
             meth = basecls.__dict__.get(name)
@@ -879,7 +886,7 @@ def getdoc(obj: Any, attrgetter: Callable = safe_getattr,
                 if doc is not None or not allow_inherited:
                     return doc
 
-    doc = attrgetter(obj, '__doc__', None)
+    doc = getdoc_internal(obj)
     if ispartial(obj) and doc == obj.__class__.__doc__:
         return getdoc(obj.func)
     elif doc is None and allow_inherited:
@@ -888,7 +895,7 @@ def getdoc(obj: Any, attrgetter: Callable = safe_getattr,
             for basecls in getmro(cls):
                 meth = safe_getattr(basecls, name, None)
                 if meth is not None:
-                    doc = attrgetter(meth, '__doc__', None)
+                    doc = getdoc_internal(meth)
                     if doc is not None:
                         break