Refactored error-generation spec to use inline fixture

spec/shoulda/matchers/active_model/helpers_spec.rb

@@ -80,16 +80,11 @@ describe Shoulda::Matchers::ActiveModel::Helpers do
 
     if active_model_3_0?
       context 'if ActiveModel::Errors#generate_message behavior has changed' do
-        subject { define_model(:divergent_example, :attr => :string) { validates_presence_of :attr }.new }
+        it 'provides the right error message for validate_presence_of' do
-
+          stub_active_model_message_generation(:type => :blank,
-        let(:message) { 'Oh snap. Behavior has diverged.' }
+                                               :message => 'Behavior has diverged.')
-
+          assert_presence_validation_has_correct_message
-        before(:each) do
-          store_translations
-          ActiveModel::Errors.any_instance.expects(:generate_message).with(:attr, :blank, {}).at_least_once.returns(message)
         end
-
-        it { should validate_presence_of(:attr) }
       end
     end
   end
@@ -152,4 +147,12 @@ describe Shoulda::Matchers::ActiveModel::Helpers do
 
     I18n.backend.store_translations(:en, translations)
   end
+
+  def stub_active_model_message_generation(options = {})
+    attribute = options.delete(:attribute) || :attr
+    message = options.delete(:message)
+    type = options.delete(:type)
+
+    ActiveModel::Errors.any_instance.expects(:generate_message).with(attribute, type, {}).at_least_once.returns(message)
+  end
 end