Check complete ancestry of text nodes for smartquotes eligibility.

Fixes sphinx-doc/sphinx#9564.

1 files changed, 9 insertions, 7 deletions

diff --git a/sphinx/util/nodes.py b/sphinx/util/nodes.py
index 7ce0933c6..78663e4c7 100644
--- a/sphinx/util/nodes.py
+++ b/sphinx/util/nodes.py
@@ -589,14 +589,16 @@ NON_SMARTQUOTABLE_PARENT_NODES = (
 
 def is_smartquotable(node: Node) -> bool:
     """Check whether the node is smart-quotable or not."""
-    if isinstance(node.parent, NON_SMARTQUOTABLE_PARENT_NODES):
-        return False
-    elif node.parent.get('support_smartquotes', None) is False:
-        return False
-    elif getattr(node, 'support_smartquotes', None) is False:
+    for pnode in traverse_parent(node.parent):
+        if isinstance(pnode, NON_SMARTQUOTABLE_PARENT_NODES):
+            return False
+        elif pnode.get('support_smartquotes', None) is False:
+            return False
+
+    if getattr(node, 'support_smartquotes', None) is False:
         return False
-    else:
-        return True
+
+    return True
 
 
 def process_only_nodes(document: Node, tags: "Tags") -> None: