SphinxTranslator calls visitor/departure method for super node class

1 files changed, 40 insertions, 1 deletions

diff --git a/sphinx/util/docutils.py b/sphinx/util/docutils.py
index a44d8bd2e..23f2c888b 100644
--- a/sphinx/util/docutils.py
+++ b/sphinx/util/docutils.py
@@ -452,7 +452,10 @@ class ReferenceRole(SphinxRole):
 class SphinxTranslator(nodes.NodeVisitor):
     """A base class for Sphinx translators.
 
-    This class provides helper methods for Sphinx translators.
+    This class adds a support for visitor/departure method for super node class
+    if visitor/departure method for node class is not found.
+
+    It also provides helper methods for Sphinx translators.
 
     .. note:: The subclasses of this class might not work with docutils.
               This class is strongly coupled with Sphinx.
@@ -464,6 +467,42 @@ class SphinxTranslator(nodes.NodeVisitor):
         self.config = builder.config
         self.settings = document.settings
 
+    def dispatch_visit(self, node):
+        """
+        Dispatch node to appropriate visitor method.
+        The priority of visitor method is:
+
+        1. ``self.visit_{node_class}()``
+        2. ``self.visit_{supre_node_class}()``
+        3. ``self.unknown_visit()``
+        """
+        for node_class in node.__class__.__mro__:
+            method = getattr(self, 'visit_%s' % (node_class.__name__), None)
+            if method:
+                logger.debug('SphinxTranslator.dispatch_visit calling %s for %s' %
+                             (method.__name__, node))
+                return method(node)
+        else:
+            super().dispatch_visit(node)
+
+    def dispatch_departure(self, node):
+        """
+        Dispatch node to appropriate departure method.
+        The priority of departure method is:
+
+        1. ``self.depart_{node_class}()``
+        2. ``self.depart_{super_node_class}()``
+        3. ``self.unknown_departure()``
+        """
+        for node_class in node.__class__.__mro__:
+            method = getattr(self, 'depart_%s' % (node_class.__name__), None)
+            if method:
+                logger.debug('SphinxTranslator.dispatch_departure calling %s for %s' %
+                             (method.__name__, node))
+                return method(node)
+        else:
+            super().dispatch_departure(node)
+
 
 # cache a vanilla instance of nodes.document
 # Used in new_document() function