[Bf-blender-cvs] [2b5733ff012] master: Fix T91192: Context.copy() crashes on file load

[Campbell Barton]

Commit: 2b5733ff0122859b713ad9199d715add496c1608
Author: Campbell Barton
Date:   Fri Sep 24 21:10:02 2021 +1000
Branches: master
https://developer.blender.org/rB2b5733ff0122859b713ad9199d715add496c1608

Fix T91192: Context.copy() crashes on file load

The `ui_list` lookup from 87c1c8112fa44ccb94a3e996b7499d6577d85d7f
didn't account for the region being unset.

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

M	source/blender/editors/screen/screen_context.c

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

diff --git a/source/blender/editors/screen/screen_context.c b/source/blender/editors/screen/screen_context.c
index 2ccefb993c7..3d447d90626 100644
--- a/source/blender/editors/screen/screen_context.c
+++ b/source/blender/editors/screen/screen_context.c
@@ -1073,9 +1073,14 @@ static eContextResult screen_ctx_ui_list(const bContext *C, bContextDataResult *
 {
   wmWindow *win = CTX_wm_window(C);
   ARegion *region = CTX_wm_region(C);
-  uiList *list = UI_list_find_mouse_over(region, win->eventstate);
-  CTX_data_pointer_set(result, NULL, &RNA_UIList, list);
-  return CTX_RESULT_OK;
+  if (region) {
+    uiList *list = UI_list_find_mouse_over(region, win->eventstate);
+    if (list) {
+      CTX_data_pointer_set(result, NULL, &RNA_UIList, list);
+      return CTX_RESULT_OK;
+    }
+  }
+  return CTX_RESULT_NO_DATA;
 }
 
 /* Registry of context callback functions. */