Util.get_blueprint could be called with a nil itemstack in some circumstances, which would cause it to fail. It now returns nil in this case.

Fixes an issue with migrating the GUI and doing initial setup for it.

Author: dewiniaid

README.md

@@ -46,6 +46,9 @@ discussion page, and messages posted there will likely be ignored.**
 
 ## Changelog
 
+### 0.4.3 (2019-04-01)
+* Fix yet another crash on loading a save that had an old version of Blueprint Extensions (only on some systems)
+
 ### 0.4.2 (2019-04-01)
 * Fix another crash on loading a save that had an old version of Blueprint Extensions (only on some systems)
 

changelog.txt

@@ -1,3 +1,9 @@
+Version: 0.4.3
+---------------------------------------------------------------------------------------------------
+Date: 01. 04. 2019
+  Bugfixes:
+    - Fix another crash on loading a save that had an old version of Blueprint Extensions (only on some systems)
+
 Version: 0.4.2
 ---------------------------------------------------------------------------------------------------
 Date: 01. 04. 2019

info.json

@@ -1,6 +1,6 @@
 {
     "name": "BlueprintExtensions",
-    "version": "0.4.2",
+    "version": "0.4.3",
     "title": "Blueprint Extensions",
     "author": "Dewin",
     "contact": "https://github.com/dewiniaid/BlueprintExtensions",

util.lua

@@ -4,7 +4,7 @@ local Util = {}
 
 -- Returns the item if it is a blueprint, the selected blueprint in the book if it is a blueprint book, or nil.
 function Util.get_blueprint(bp)
-    if not (bp.valid and bp.valid_for_read) then
+    if not (bp and bp.valid and bp.valid_for_read) then
         return nil
     end
     if bp.is_blueprint_book and bp.active_index then