Generated scaffold functional tests use assert_difference. Closes #8421.

git-svn-id: http://svn-commit.rubyonrails.org/rails/trunk@6808 5ecf4fe2-1ee6-0310-87b1-e25e094e27de

railties/CHANGELOG

 *SVN*
 
+* Generated scaffold functional tests use assert_difference.  #8421 [norbert]
+
 * Update to Prototype 1.5.1.  [Sam Stephenson]
 
 * Update to script.aculo.us 1.7.1_beta3.  [Thomas Fuchs]

railties/lib/rails_generator/generators/components/scaffold/templates/functional_test.rb

@@ -25,9 +25,9 @@ def test_should_get_new
   end
   
   def test_should_create_<%= file_name %>
-    old_count = <%= class_name %>.count
-    post :create, :<%= file_name %> => { }
-    assert_equal old_count+1, <%= class_name %>.count
+    assert_difference('<%= class_name %>.count') do
+      post :create, :<%= file_name %> => { }
+    end
     
     assert_redirected_to <%= file_name %>_path(assigns(:<%= file_name %>))
   end
@@ -48,9 +48,9 @@ def test_should_update_<%= file_name %>
   end
   
   def test_should_destroy_<%= file_name %>
-    old_count = <%= class_name %>.count
-    delete :destroy, :id => 1
-    assert_equal old_count-1, <%= class_name %>.count
+    assert_difference('<%= class_name %>.count', -1) do
+      delete :destroy, :id => 1
+    end
     
     assert_redirected_to <%= table_name %>_path
   end