Install Spring preloader when generating new applications

2 files changed, 26 insertions, 1 deletions

diff --git a/railties/lib/rails/generators/app_base.rb b/railties/lib/rails/generators/app_base.rb
index 2022b4ed3d..5d4682f6e3 100644
--- a/railties/lib/rails/generators/app_base.rb
+++ b/railties/lib/rails/generators/app_base.rb
@@ -47,6 +47,9 @@ module Rails
         class_option :skip_sprockets,     type: :boolean, aliases: '-S', default: false,
                                           desc: 'Skip Sprockets files'
 
+        class_option :skip_spring,        type: :boolean, default: false,
+                                          desc: "Don't install Spring application preloader"
+
         class_option :database,           type: :string, aliases: '-d', default: 'sqlite3',
                                           desc: "Preconfigure for selected database (options: #{DATABASES.join('/')})"
 
@@ -109,6 +112,7 @@ module Rails
           jbuilder_gemfile_entry,
           sdoc_gemfile_entry,
           platform_dependent_gemfile_entry,
+          spring_gemfile_entry,
           @extra_entries].flatten.find_all(&@gem_filter)
       end
 
@@ -365,6 +369,12 @@ module Rails
         end
       end
 
+      def spring_gemfile_entry
+        return [] unless spring_install?
+        comment = 'Spring speeds up development by keeping your application running in the background. Read more: https://github.com/jonleighton/spring'
+        GemfileEntry.new('spring', nil, comment, group: :development)
+      end
+
       def bundle_command(command)
         say_status :run, "bundle #{command}"
 
@@ -388,8 +398,22 @@ module Rails
         end
       end
 
+      def bundle_install?
+        !(options[:skip_gemfile] || options[:skip_bundle] || options[:pretend])
+      end
+
+      def spring_install?
+        !options[:skip_spring] && Process.respond_to?(:fork)
+      end
+
       def run_bundle
-        bundle_command('install') unless options[:skip_gemfile] || options[:skip_bundle] || options[:pretend]
+        bundle_command('install') if bundle_install?
+      end
+
+      def generate_spring_binstubs
+        if bundle_install? && spring_install?
+          bundle_command("exec spring binstub --all")
+        end
       end
 
       def empty_directory_with_keep_file(destination, config = {})
diff --git a/railties/lib/rails/generators/rails/app/app_generator.rb b/railties/lib/rails/generators/rails/app/app_generator.rb
index a2023886cd..87556bd609 100644
--- a/railties/lib/rails/generators/rails/app/app_generator.rb
+++ b/railties/lib/rails/generators/rails/app/app_generator.rb
@@ -237,6 +237,7 @@ module Rails
 
       public_task :run_bundle
       public_task :replay_template
+      public_task :generate_spring_binstubs
 
     protected