Nodes: debug print for bNodeTreeZones

Pull Request: https://projects.blender.org/blender/blender/pulls/116903

source/blender/blenkernel/BKE_node_tree_zones.hh

@@ -8,6 +8,8 @@
  * \ingroup bke
  */
 
+#include <iosfwd>
+
 #include "DNA_node_types.h"
 
 #include "BLI_vector.hh"
@@ -42,6 +44,8 @@ class bNodeTreeZone {
 
   bool contains_node_recursively(const bNode &node) const;
   bool contains_zone_recursively(const bNodeTreeZone &other_zone) const;
+
+  friend std::ostream &operator<<(std::ostream &stream, const bNodeTreeZone &zone);
 };
 
 class bNodeTreeZones {
@@ -72,6 +76,8 @@ class bNodeTreeZones {
    * nested zone. For nodes that are at the root level, the returned list is empty.
    */
   Vector<const bNodeTreeZone *> get_zone_stack_for_node(const int32_t node_id) const;
+
+  friend std::ostream &operator<<(std::ostream &stream, const bNodeTreeZones &zones);
 };
 
 const bNodeTreeZones *get_tree_zones(const bNodeTree &tree);

source/blender/blenkernel/intern/node_tree_zones.cc

@@ -2,6 +2,8 @@
  *
  * SPDX-License-Identifier: GPL-2.0-or-later */
 
+#include <iostream>
+
 #include "BKE_node.hh"
 #include "BKE_node_runtime.hh"
 #include "BKE_node_tree_zones.hh"
@@ -351,6 +353,7 @@ static std::unique_ptr<bNodeTreeZones> discover_tree_zones(const bNodeTree &tree
 
   update_zone_border_links(tree, *tree_zones);
 
+  // std::cout << *tree_zones << std::endl;
   return tree_zones;
 }
 
@@ -522,4 +525,37 @@ const bNodeZoneType *zone_type_by_node_type(const int node_type)
   return nullptr;
 }
 
+std::ostream &operator<<(std::ostream &stream, const bNodeTreeZones &zones)
+{
+  for (const std::unique_ptr<bNodeTreeZone> &zone : zones.zones) {
+    stream << *zone;
+    if (zones.zones.last().get() != zone.get()) {
+      stream << "\n";
+    }
+  }
+  return stream;
+}
+
+std::ostream &operator<<(std::ostream &stream, const bNodeTreeZone &zone)
+{
+  stream << zone.index << ": Parent index: ";
+  if (zone.parent_zone != nullptr) {
+    stream << zone.parent_zone->index;
+  }
+  else {
+    stream << "*";
+  }
+
+  stream << "; Input: " << (zone.input_node ? zone.input_node->name : "null");
+  stream << ", Output: " << (zone.output_node ? zone.output_node->name : "null");
+
+  stream << "; Border Links: {\n";
+  for (const bNodeLink *border_link : zone.border_links) {
+    stream << "  " << border_link->fromnode->name << ": " << border_link->fromsock->name << " -> ";
+    stream << border_link->tonode->name << ": " << border_link->tosock->name << ";\n";
+  }
+  stream << "}.";
+  return stream;
+}
+
 }  // namespace blender::bke