Fix ID user counting issues with NodeCustomGroup.

User counting now happens before init() and after free() methods, so that
the ID users are in a valid state when Python might modify them. ID user
counting was moved into node.c and simplified.

Patch by Miguel with further refactoring by Brecht. Ref D4370.

3 files changed, 5 insertions, 14 deletions

diff --git a/source/blender/editors/space_node/node_edit.c b/source/blender/editors/space_node/node_edit.c
index b1cada9752a..1a18e886808 100644
--- a/source/blender/editors/space_node/node_edit.c
+++ b/source/blender/editors/space_node/node_edit.c
@@ -1590,11 +1590,8 @@ static int node_delete_exec(bContext *C, wmOperator *UNUSED(op))
 	for (node = snode->edittree->nodes.first; node; node = next) {
 		next = node->next;
 		if (node->flag & SELECT) {
-			/* check id user here, nodeFreeNode is called for free dbase too */
 			do_tag_update |= (do_tag_update || node_connected_to_output(bmain, snode->edittree, node));
-			if (node->id)
-				id_us_min(node->id);
-			nodeDeleteNode(bmain, snode->edittree, node);
+			nodeRemoveNode(bmain, snode->edittree, node, true);
 		}
 	}
 
@@ -1684,11 +1681,7 @@ static int node_delete_reconnect_exec(bContext *C, wmOperator *UNUSED(op))
 		next = node->next;
 		if (node->flag & SELECT) {
 			nodeInternalRelink(snode->edittree, node);
-
-			/* check id user here, nodeFreeNode is called for free dbase too */
-			if (node->id)
-				id_us_min(node->id);
-			nodeDeleteNode(bmain, snode->edittree, node);
+			nodeRemoveNode(bmain, snode->edittree, node, true);
 		}
 	}
 
diff --git a/source/blender/editors/space_node/node_group.c b/source/blender/editors/space_node/node_group.c
index 8c5bf60bc5d..808d9375d22 100644
--- a/source/blender/editors/space_node/node_group.c
+++ b/source/blender/editors/space_node/node_group.c
@@ -337,11 +337,11 @@ static int node_group_ungroup(Main *bmain, bNodeTree *ntree, bNode *gnode)
 
 	while (nodes_delayed_free) {
 		node = BLI_linklist_pop(&nodes_delayed_free);
-		nodeDeleteNode(bmain, ntree, node);
+		nodeRemoveNode(bmain, ntree, node, false);
 	}
 
 	/* delete the group instance */
-	nodeDeleteNode(bmain, ntree, gnode);
+	nodeRemoveNode(bmain, ntree, gnode, false);
 
 	ntree->update |= NTREE_UPDATE_NODES | NTREE_UPDATE_LINKS;
 
diff --git a/source/blender/editors/space_node/node_templates.c b/source/blender/editors/space_node/node_templates.c
index aef36b49814..b3edf98c470 100644
--- a/source/blender/editors/space_node/node_templates.c
+++ b/source/blender/editors/space_node/node_templates.c
@@ -143,9 +143,7 @@ static void node_remove_linked(Main *bmain, bNodeTree *ntree, bNode *rem_node)
 		next = node->next;
 
 		if (node->flag & NODE_TEST) {
-			if (node->id)
-				id_us_min(node->id);
-			nodeDeleteNode(bmain, ntree, node);
+			nodeRemoveNode(bmain, ntree, node, true);
 		}
 	}
 }