Nodes: Make context path breadcrumbs interactive

Make it possible to navigate in/out node groups through the breacrumbs
context path overlay.

See PR for details and screenshots.

Pull Request: https://projects.blender.org/blender/blender/pulls/141292

scripts/startup/bl_operators/node.py

@@ -328,6 +328,12 @@ class NODE_OT_tree_path_parent(Operator):
     bl_label = "Parent Node Tree"
     bl_options = {'REGISTER', 'UNDO'}
 
+    parent_tree_index: IntProperty(
+        name="Parent Index",
+        description="Parent index in context path",
+        default=0,
+    )
+
     @classmethod
     def poll(cls, context):
         space = context.space_data
@@ -337,7 +343,9 @@ class NODE_OT_tree_path_parent(Operator):
     def execute(self, context):
         space = context.space_data
 
-        space.path.pop()
+        parent_number_to_pop = len(space.path) - 1 - self.parent_tree_index
+        for _ in range(parent_number_to_pop):
+            space.path.pop()
 
         return {'FINISHED'}
 

scripts/startup/bl_ui/space_node.py

@@ -193,7 +193,8 @@ class NODE_HT_header(Header):
         layout.separator_spacer()
 
         if len(snode.path) > 1:
-            layout.operator("node.tree_path_parent", text="", icon='FILE_PARENT')
+            op = layout.operator("node.tree_path_parent", text="", icon='FILE_PARENT')
+            op.parent_tree_index = len(snode.path) - 2
 
         # Backdrop
         if is_compositor: