Replace of (id->lib != NULL) check by meaningful macro.

Idea is to replace hard-to-track (id->lib != NULL) 'is linked datablock' check everywhere in Blender
by a macro doing the same thing. This will allow to easily spot those checks in future, and more importantly,
to easily change it (see work done in asset-engine branch).

Note: did not touch to readfile.c, since there most of the time 'id->lib' check actually concerns the pointer,
and not a check whether ID is linked or not. Will have a closer look at it later.

Reviewers: campbellbarton, brecht, sergey

Differential Revision: https://developer.blender.org/D2082

1 files changed, 1 insertions, 1 deletions

diff --git a/source/blender/editors/interface/interface_regions.c b/source/blender/editors/interface/interface_regions.c
index d4d3e1af1fd..575b32e81e8 100644
--- a/source/blender/editors/interface/interface_regions.c
+++ b/source/blender/editors/interface/interface_regions.c
@@ -454,7 +454,7 @@ static uiTooltipData *ui_tooltip_data_from_button(bContext *C, uiBut *but)
 
 		if (but->rnapoin.id.data) {
 			ID *id = but->rnapoin.id.data;
-			if (id->lib) {
+			if (ID_IS_LINKED_DATABLOCK(id)) {
 				BLI_snprintf(data->lines[data->totline], sizeof(data->lines[0]), TIP_("Library: %s"), id->lib->name);
 				data->format[data->totline].color_id = UI_TIP_LC_NORMAL;
 				data->totline++;