don't include 'turn' gem in Gemfile if test unit is skipped.

railties/lib/rails/generators/app_base.rb

@@ -173,7 +173,7 @@ def gem_for_ruby_debugger
       end
 
       def gem_for_turn
-        unless RUBY_VERSION < "1.9.2"
+        unless RUBY_VERSION < "1.9.2" || options[:skip_test_unit]
           <<-GEMFILE.strip_heredoc
             group :test do
               # Pretty printed test output

railties/test/generators/app_generator_test.rb

@@ -210,6 +210,13 @@ def test_inclusion_of_turn_gem_in_gemfile
     end
   end
 
+  def test_turn_gem_is_not_included_in_gemfile_if_skipping_test_unit
+    run_generator [destination_root, "--skip-test-unit"]
+    assert_file "Gemfile" do |contents|
+      assert_no_match /gem 'tuarn'/, contents unless RUBY_VERSION < '1.9.2'
+    end
+  end
+
   def test_inclusion_of_ruby_debug
     run_generator
     assert_file "Gemfile" do |contents|