Working on state-machines#26, added some tests to more clearly establish the baseline, as well as to show that we aren't behaving as expected when considering "ActiveRecord::Base#save returns nil on a rolled-back transaction"

Author: rosskevin

lib/state_machines/integrations/active_record.rb

@@ -493,7 +493,8 @@ def save(*)
               end
               
               def save!(*)
-                self.class.state_machine(#{name.inspect}).send(:around_save, self) { super } || raise(ActiveRecord::RecordInvalid.new(self))
+                result = self.class.state_machine(#{name.inspect}).send(:around_save, self) { super }
+                result || raise(ActiveRecord::RecordInvalid.new(self))
               end
               
               def changed_for_autosave?

test/machine_with_event_attributes_on_save_test.rb

@@ -176,9 +176,69 @@ def test_should_allow_additional_transitions_to_previous_state_in_after_transiti
     assert_equal 'first_gear', @record.state
   end
 
-  def test_should_return_false_on_before_transition_rollback
-    @machine.before_transition { raise ActiveRecord::Rollback }
+  def test_should_yield_one_model!
+    assert_equal true, @record.save!
+    assert_equal 1, @model.count
+  end
 
-    assert_equal false, @record.save
+  # explicit tests of #save and #save! to ensure expected behavior
+  def test_should_yield_two_models_with_before
+    @machine.before_transition { @model.create! }
+    assert_equal true, @record.save
+    assert_equal 2, @model.count
   end
+
+  def test_should_yield_two_models_with_before!
+    @machine.before_transition { @model.create! }
+    assert_equal true, @record.save!
+    assert_equal 2, @model.count
+  end
+
+  def test_should_raise_on_around_transition_rollback!
+    @machine.before_transition { @model.create! }
+    @machine.around_transition { @model.create!; raise ActiveRecord::Rollback }
+
+    raised = false
+    begin
+      @record.save!
+    rescue Exception
+      raised = true
+    end
+
+    assert_equal true, raised
+    assert_equal 0, @model.count
+  end
+
+  def test_should_return_nil_on_around_transition_rollback
+    @machine.before_transition { @model.create! }
+    @machine.around_transition { @model.create!; raise ActiveRecord::Rollback }
+    assert_equal nil, @record.save
+    assert_equal 0, @model.count
+  end
+
+  def test_should_return_nil_on_before_transition_rollback
+    @machine.before_transition { raise ActiveRecord::Rollback }
+    assert_equal nil, @record.save
+    assert_equal 0, @model.count
+  end
+
+  #
+  # @rosskevin - This fails and I'm not sure why, it was existing behavior.
+  #   see: https://github.com/state-machines/state_machines-activerecord/pull/26#issuecomment-112911886
+  #
+  # def test_should_yield_three_models_with_before_and_around_save
+  #   @machine.before_transition { @model.create!; puts "before ran, now #{@model.count}" }
+  #   @machine.around_transition { @model.create!; puts "around ran, now #{@model.count}" }
+  #
+  #   assert_equal true, @record.save
+  #   assert_equal 3, @model.count
+  # end
+  #
+  # def test_should_yield_three_models_with_before_and_around_save!
+  #   @machine.before_transition { @model.create!; puts "before ran, now #{@model.count}" }
+  #   @machine.around_transition { @model.create!; puts "around ran, now #{@model.count}" }
+  #
+  #   assert_equal true, @record.save!
+  #   assert_equal 3, @model.count
+  # end
 end