source/blender/blenloader/intern/readfile.cc

@@ -2061,6 +2061,10 @@ static void direct_link_id_common(
   }
 
   id->lib = current_library;
+  if (id->lib) {
+    /* Always fully clear fake user flag for linked data. */
+    id->flag &= ~LIB_FAKEUSER;
+  }
   id->us = ID_FAKE_USERS(id);
   id->icon_id = 0;
   id->newid = nullptr; /* Needed because .blend may have been saved with crap value here... */

source/blender/blenloader/intern/writefile.cc

@@ -1225,16 +1225,6 @@ static bool write_file_handle(Main *mainvar,
            * asap afterward. */
           id_lib_extern(id_iter);
         }
-        else if (ID_FAKE_USERS(id_iter) > 0 && id_iter->asset_data == nullptr) {
-          /* Even though fake user is not directly editable by the user on linked data, it is a
-           * common 'work-around' to set it in library files on data-blocks that need to be linked
-           * but typically do not have an actual real user (e.g. texts, etc.).
-           * See e.g. #105687 and #103867.
-           *
-           * Would be good to find a better solution, but for now consider these as directly linked
-           * as well. */
-          id_lib_extern(id_iter);
-        }
         else {
           id_iter->tag |= LIB_TAG_INDIRECT;
           id_iter->tag &= ~LIB_TAG_EXTERN;

tests/python/bl_blendfile_io.py

@@ -115,10 +115,11 @@ class TestIdRuntimeTag(TestHelper):
         assert linked_material.is_library_indirect is False
 
         link_dir = os.path.join(output_lib_path, "Mesh")
-        bpy.ops.wm.link(directory=link_dir, filename="LibMesh")
+        bpy.ops.wm.link(directory=link_dir, filename="LibMesh", instance_object_data=False)
 
         linked_mesh = bpy.data.meshes['LibMesh']
         assert linked_mesh.is_library_indirect is False
+        assert linked_mesh.use_fake_user is False
 
         obj.data = linked_mesh
         obj.material_slots[0].link = 'OBJECT'
@@ -131,17 +132,15 @@ class TestIdRuntimeTag(TestHelper):
         # so writing .blend file will have properly reset its tag to indirectly linked data.
         assert linked_material.is_library_indirect
 
-        # Only usage of this linked mesh is a runtime ID (object), but it is flagged as 'fake user' in its library,
-        # so writing .blend file will have kept its tag to directly linked data.
-        assert not linked_mesh.is_library_indirect
+        # Only usage of this linked mesh is a runtime ID (object),
+        # so writing .blend file will have properly reset its tag to indirectly linked data.
+        assert linked_mesh.is_library_indirect
 
         bpy.ops.wm.open_mainfile(filepath=output_work_path, load_ui=False)
 
         assert 'Cube' not in bpy.data.objects
-        assert 'LibMaterial' in bpy.data.materials  # Pulled-in by the linked mesh.
-        linked_mesh = bpy.data.meshes['LibMesh']
-        assert linked_mesh.use_fake_user is True
-        assert linked_mesh.is_library_indirect is False
+        assert 'LibMaterial' not in bpy.data.materials
+        assert 'libMesh' not in bpy.data.meshes
 
 
 TESTS = (

tests/python/bl_blendfile_liblink.py

@@ -214,9 +214,9 @@ class TestBlendLibLinkIndirect(TestBlendLibLinkHelper):
         material = bpy.data.materials[0]
 
         assert material.library is not None
-        assert material.use_fake_user is True
-        assert material.users == 2  # Fake user is not cleared when linking.
-        assert material.is_library_indirect
+        assert material.use_fake_user is False  # Fake user is cleared when linking.
+        assert material.users == 1
+        assert material.is_library_indirect is True
 
         assert mesh.library is not None
         assert mesh.use_fake_user is False
@@ -229,29 +229,28 @@ class TestBlendLibLinkIndirect(TestBlendLibLinkHelper):
         coll.objects.link(ob)
         bpy.context.scene.collection.children.link(coll)
 
-        assert material.users == 2
-        assert material.is_library_indirect
+        assert material.users == 1
+        assert material.is_library_indirect is True
         assert mesh.users == 1
         assert mesh.is_library_indirect is False
 
         ob.material_slots[0].link = 'OBJECT'
         ob.material_slots[0].material = material
 
-        assert material.users == 3
+        assert material.users == 2
         assert material.is_library_indirect is False
 
         ob.material_slots[0].material = None
 
-        assert material.users == 2
+        assert material.users == 1
         # This is not properly updated whene removing a local user of linked data.
         assert material.is_library_indirect is False
 
         output_work_path = os.path.join(output_dir, self.unique_blendfile_name("blendfile"))
         bpy.ops.wm.save_as_mainfile(filepath=output_work_path, check_existing=False, compress=False)
 
-        assert material.users == 2
-        # Currently linked data with 'fake user' set are considered as directly linked data.
-        assert not material.is_library_indirect
+        assert material.users == 1
+        assert material.is_library_indirect is True
 
         bpy.ops.wm.open_mainfile(filepath=output_work_path, load_ui=False)
 
@@ -264,10 +263,9 @@ class TestBlendLibLinkIndirect(TestBlendLibLinkHelper):
         material = bpy.data.materials[0]
 
         assert material.library is not None
-        assert material.use_fake_user is True
-        assert material.users == 2  # Fake user is not cleared when linking.
-        # Currently linked data with 'fake user' set are considered as directly linked data.
-        assert not material.is_library_indirect
+        assert material.use_fake_user is False  # Fake user is cleared when linking.
+        assert material.users == 1
+        assert material.is_library_indirect is True
 
         assert mesh.library is not None
         assert mesh.use_fake_user is False
@@ -293,7 +291,7 @@ class TestBlendLibAppendBasic(TestBlendLibLinkHelper):
 
         assert len(bpy.data.materials) == 1
         assert bpy.data.materials[0].library is not None
-        assert bpy.data.materials[0].users == 2  # Fake user is not cleared when linking.
+        assert bpy.data.materials[0].users == 1  # Fake user is cleared when linking.
         assert len(bpy.data.meshes) == 1
         assert bpy.data.meshes[0].library is None
         assert bpy.data.meshes[0].use_fake_user is False
@@ -310,7 +308,7 @@ class TestBlendLibAppendBasic(TestBlendLibLinkHelper):
 
         assert len(bpy.data.materials) == 1
         assert bpy.data.materials[0].library is not None
-        assert bpy.data.materials[0].users == 2  # Fake user is not cleared when linking.
+        assert bpy.data.materials[0].users == 1  # Fake user is cleared when linking.
         assert len(bpy.data.meshes) == 1
         assert bpy.data.meshes[0].library is None
         assert bpy.data.meshes[0].use_fake_user is False
@@ -328,7 +326,7 @@ class TestBlendLibAppendBasic(TestBlendLibLinkHelper):
 
         assert len(bpy.data.materials) == 1
         assert bpy.data.materials[0].library is not None
-        assert bpy.data.materials[0].users == 2  # Fake user is not cleared when linking.
+        assert bpy.data.materials[0].users == 1  # Fake user is cleared when linking.
         assert len(bpy.data.meshes) == 1
         assert bpy.data.meshes[0].library is None
         assert bpy.data.meshes[0].use_fake_user is True
@@ -345,7 +343,7 @@ class TestBlendLibAppendBasic(TestBlendLibLinkHelper):
 
         assert len(bpy.data.materials) == 1
         assert bpy.data.materials[0].library is not None
-        assert bpy.data.materials[0].users == 2  # Fake user is not cleared when linking.
+        assert bpy.data.materials[0].users == 1  # Fake user is cleared when linking.
         assert len(bpy.data.meshes) == 1
         assert bpy.data.meshes[0].library is None
         assert bpy.data.meshes[0].users == 1