[Bf-blender-cvs] [08f7b20] blender-v2.74-release: Bugfix: Fix for crash when trying to create new action in Shape Key DopeSheet mode

[Joshua Leung]

Commit: 08f7b20ebb5ab2746144663876d19086f7518939
Author: Joshua Leung
Date:   Sat Mar 28 23:22:02 2015 +1300
Branches: blender-v2.74-release
https://developer.blender.org/rB08f7b20ebb5ab2746144663876d19086f7518939

Bugfix: Fix for crash when trying to create new action in Shape Key DopeSheet mode

When the active object had no shapekey data, trying to create a new action from the
Shape Keys mode of the DopeSheet would crash. The segfault here was a silly regression
caused by my earlier Action Stashing work.

However, the old (pre-Action Stashing) code here also wasn't that great either.
While it didn't crash, it would still silently create a new action, even if that
could not get assigned/used anywhere. To prevent both of these problems from
happening again, I've added additional null checks, as well as beefing up the poll
callback here to forbid keyframing

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

M	source/blender/editors/space_action/action_edit.c

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

diff --git a/source/blender/editors/space_action/action_edit.c b/source/blender/editors/space_action/action_edit.c
index 76c955d..95066b9 100644
--- a/source/blender/editors/space_action/action_edit.c
+++ b/source/blender/editors/space_action/action_edit.c
@@ -93,11 +93,15 @@ static AnimData *actedit_animdata_from_context(bContext *C)
 	/* Get AnimData block to use */
 	if (saction->mode == SACTCONT_ACTION) {
 		/* Currently, "Action Editor" means object-level only... */
-		adt = ob->adt;
+		if (ob) {
+			adt = ob->adt;
+		}
 	}
 	else if (saction->mode == SACTCONT_SHAPEKEY) {
 		Key *key = BKE_key_from_object(ob);
-		adt = key->adt;
+		if (key) {
+			adt = key->adt;
+		}
 	}
 	
 	return adt;
@@ -180,9 +184,19 @@ static int action_new_poll(bContext *C)
 	if (!(scene->flag & SCE_NLA_EDIT_ON)) {
 		if (ED_operator_action_active(C)) {
 			SpaceAction *saction = (SpaceAction *)CTX_wm_space_data(C);
+			Object *ob = CTX_data_active_object(C);
 			
 			/* For now, actions are only for the active object, and on object and shapekey levels... */
-			return ELEM(saction->mode, SACTCONT_ACTION, SACTCONT_SHAPEKEY);
+			if (saction->mode == SACTCONT_ACTION) {
+				/* XXX: This assumes that actions are assigned to the active object */
+				if (ob)
+					return true;
+			}
+			else if (saction->mode == SACTCONT_SHAPEKEY) {
+				Key *key = BKE_key_from_object(ob);
+				if (key)
+					return true;
+			}
 		}
 		else if (ED_operator_nla_active(C)) {
 			return true;