Merge pull request #508 from gocardless/vsavin/fix-reset-for-empty-cache

Handle the case where the cache is empty

CHANGELOG.md

@@ -1,3 +1,8 @@
+## v10.2.1 3rd April 2023
+
+### Changed
+- Fixed an edge case where `adapter.reset` were failing if the cache is empty
+
 ## v10.2.0 3rd April 2023
 
 ### Changed

lib/statesman/adapters/active_record.rb

@@ -52,7 +52,7 @@ def create(from, to, metadata = {})
 
         raise
       ensure
-        remove_instance_variable(:@last_transition)
+        reset
       end
 
       def history(force_reload: false)
@@ -76,7 +76,8 @@ def last(force_reload: false)
       end
 
       def reset
-        remove_instance_variable(:@last_transition)
+        remove_instance_variable(:@last_transition) \
+          if instance_variable_defined?(:@last_transition)
       end
 
       private

lib/statesman/version.rb

@@ -1,5 +1,5 @@
 # frozen_string_literal: true
 
 module Statesman
-  VERSION = "10.2.0"
+  VERSION = "10.2.1"
 end

spec/statesman/adapters/active_record_spec.rb

@@ -388,6 +388,12 @@
     end
   end
 
+  describe "#reset" do
+    it "works with empty cache" do
+      expect { model.state_machine.reset }.to_not raise_error
+    end
+  end
+
   it "resets last with #reload" do
     model.save!
     ActiveRecord::Base.transaction do