[Bf-blender-cvs] [248d9809cab] master: Fix T86594: Overrides: Possible collection "duplication".

[Bastien Montagne]

Commit: 248d9809cabe483049fdc50f777a540180b4635b
Author: Bastien Montagne
Date:   Thu Mar 18 14:25:23 2021 +0100
Branches: master
https://developer.blender.org/rB248d9809cabe483049fdc50f777a540180b4635b

Fix T86594: Overrides: Possible collection "duplication".

Issue was actually in some Collection management code, a bit too eager
to add collection to the scene master one when it was not actually
needed.

===================================================================

M	source/blender/blenkernel/intern/collection.c

===================================================================

diff --git a/source/blender/blenkernel/intern/collection.c b/source/blender/blenkernel/intern/collection.c
index 4e4134c7c8f..178a762fd40 100644
--- a/source/blender/blenkernel/intern/collection.c
+++ b/source/blender/blenkernel/intern/collection.c
@@ -485,6 +485,11 @@ void BKE_collection_add_from_collection(Main *bmain,
       collection_child_add(collection, collection_dst, 0, true);
       is_instantiated = true;
     }
+    else if (!is_instantiated && collection_find_child(collection, collection_dst)) {
+      /* If given collection_dst is already instantiated in scene, even if its 'model' src one is
+       * not, do not add it to master scene collection. */
+      is_instantiated = true;
+    }
   }
   FOREACH_SCENE_COLLECTION_END;