include spring-watcher-listen in the Gemfile of new applications

railties/CHANGELOG.md

@@ -1,3 +1,8 @@
+*   The Gemfiles of new applications include spring-watcher-listen on Linux and
+    Mac OS X (unless --skip-spring).
+
+    *Xavier Noria*
+
 *   New applications are generated with the evented file system monitor enabled
     on Linux and Mac OS X.
 

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

@@ -44,6 +44,9 @@ group :development do
 <% if spring_install? -%>
   # Spring speeds up development by keeping your application running in the background. Read more: https://github.com/rails/spring
   gem 'spring'
+<% if os_supports_listen_out_of_the_box? -%>
+  gem 'spring-watcher-listen', '~> 2.0.0'
+<% end -%>
 <% end -%>
 end
 <% end -%>

railties/test/generators/app_generator_test.rb

@@ -483,6 +483,7 @@ class AppGeneratorTest < Rails::Generators::TestCase
     run_generator
     if RbConfig::CONFIG['host_os'] =~ /darwin|linux/
       assert_gem 'listen'
+      assert_gem 'spring-watcher-listen'
     else
       assert_file 'Gemfile' do |content|
         assert_no_match(/listen/, content)