Merge pull request #341 from pirj/fix-lazy-exception

Fix lazy error message messing up originating state

lib/aasm/errors.rb

@@ -3,18 +3,18 @@ module AASM
   class UnknownStateMachineError < RuntimeError; end
 
   class InvalidTransition < RuntimeError
-    attr_reader :object, :event_name, :state_machine_name, :failures
+    attr_reader :object, :event_name, :originating_state, :failures
 
     def initialize(object, event_name, state_machine_name, failures = [])
-      @object, @event_name, @state_machine_name, @failures = object, event_name, state_machine_name, failures
+      @object, @event_name, @originating_state, @failures = object, event_name, object.aasm(state_machine_name).current_state, failures
     end
 
     def message
-      "Event '#{event_name}' cannot transition from '#{object.aasm(state_machine_name).current_state}'. #{reasoning}"
+      "Event '#{event_name}' cannot transition from '#{originating_state}'. #{reasoning}"
     end
 
     def reasoning
-      "Failed callback(s): #{@failures}." unless failures.empty?
+      "Failed callback(s): #{failures}." unless failures.empty?
     end
   end
 

spec/unit/exception_spec.rb

@@ -0,0 +1,11 @@
+require 'spec_helper'
+
+describe AASM::InvalidTransition do
+  it 'should not be lazy detecting originating state' do
+    process = ProcessWithNewDsl.new
+    expect { process.stop! }.to raise_error do |err|
+      process.start
+      expect(err.message).to eql("Event 'stop' cannot transition from 'sleeping'. ")
+    end
+  end
+end