Python node operator for combined node collapsing and hiding unused sockets. Socket hide flag is added to RNA as well, but can only be set when the socket is not connected, to avoid dangling links in editor drawing. Currently this operator has no default hotkey, but can be called from the Node menu.

release/scripts/startup/bl_operators/node.py

@@ -134,3 +134,34 @@ class NODE_OT_add_search(Operator):
 
         context.window_manager.invoke_search_popup(self)
         return {'CANCELLED'}
+
+
+class NODE_OT_collapse_hide_unused_toggle(Operator):
+    '''Toggle collapsed nodes and hide unused sockets'''
+    bl_idname = "node.collapse_hide_unused_toggle"
+    bl_label = "Collapse and Hide Unused Sockets"
+    bl_options = {'REGISTER', 'UNDO'}
+
+    @classmethod
+    def poll(cls, context):
+        space = context.space_data
+        # needs active node editor and a tree
+        return space.type == 'NODE_EDITOR' and space.edit_tree
+
+    def execute(self, context):
+        space = context.space_data
+        tree = space.edit_tree
+
+        for node in tree.nodes:
+            if node.select:
+                hide = not node.hide
+                
+                node.hide = hide
+                # Note: connected sockets are ignored internally
+                for socket in node.inputs:
+                    socket.hide = hide
+                for socket in node.outputs:
+                    socket.hide = hide
+                    
+        return {'FINISHED'}
+