make turn a soft dependency. generate a Gemfile that contains turn and require turn if it is available

railties/lib/rails/generators/rails/app/templates/Gemfile

@@ -23,9 +23,13 @@ source 'http://rubygems.org'
 # Bundle gems for the local environment. Make sure to
 # put test-only gems in this group so their generators
 # and rake tasks are available in development mode:
-# group :development, :test do
-#   gem 'webrat'
-# end
+
+group :development, :test do
+  # Depend "turn" for pretty printing test output, but disable autorequire.
+  gem 'turn', :require => false
+
+  # gem 'webrat'
+end
 
 # Needed for guides generation
 # gem "RedCloth", "~> 4.2"

railties/lib/rails/test_help.rb

@@ -14,10 +14,14 @@
 end
 
 if defined?(MiniTest)
-  require 'turn'
+  # Enable turn if it is available
+  begin
+    require 'turn'
 
-  if MiniTest::Unit.respond_to?(:use_natural_language_case_names=)
-    MiniTest::Unit.use_natural_language_case_names = true 
+    if MiniTest::Unit.respond_to?(:use_natural_language_case_names=)
+      MiniTest::Unit.use_natural_language_case_names = true
+    end
+  rescue LoadError
   end
 end
 

railties/railties.gemspec

@@ -21,7 +21,6 @@
   s.add_dependency('rake',          '>= 0.8.7')
   s.add_dependency('thor',          '~> 0.14.4')
   s.add_dependency('rack-ssl',      '~> 1.3.2')
-  s.add_dependency('turn',          '~> 0.8.2')
   s.add_dependency('activesupport', version)
   s.add_dependency('actionpack',    version)
 end