Merge branch 'master' into laurocaetano-fix_send_file

* master: (536 commits)
  doc, API example on how to use `Model#exists?` with multiple IDs. [ci skip]
  Restore DATABASE_URL even if it's nil in connection_handler test
  [ci skip] - error_messages_for has been deprecated since 2.3.8 - lets reduce any confusion for users
  Ensure Active Record connection consistency
  Revert "ask the fixture set for the sql statements"
  Check `respond_to` before delegation due to: https://github.com/ruby/ruby/commit/d781caaf313b8649948c107bba277e5ad7307314
  Adding Hash#compact and Hash#compact! methods
  MySQL version 4.1 was EOL on December 31, 2009 We should at least recommend modern versions of MySQL to users.
  clear cache on body close so that cache remains during rendering
  add a more restricted codepath for templates fixes #13390
  refactor generator tests to use block form of Tempfile
  Fix typo [ci skip]
  Move finish_template as the last public method in the generator
  Minor typos fix [ci skip]
  make `change_column_null` reversible. Closes #13576.
  create/drop test and development databases only if RAILS_ENV is nil
  Revert "Speedup String#to"
  typo fix in test name. [ci skip].
  `core_ext/string/access.rb` test what we are documenting.
  Fix typo in image_tag documentation
  ...

Conflicts:
	actionpack/CHANGELOG.md

30 files changed, 209 insertions, 76 deletions

diff --git a/railties/lib/rails/generators/actions.rb b/railties/lib/rails/generators/actions.rb
index 366c72ebaa..afdbf5c241 100644
--- a/railties/lib/rails/generators/actions.rb
+++ b/railties/lib/rails/generators/actions.rb
@@ -9,7 +9,7 @@ module Rails
         @in_group = nil
       end
 
-      # Adds an entry into Gemfile for the supplied gem.
+      # Adds an entry into +Gemfile+ for the supplied gem.
       #
       #   gem "rspec", group: :test
       #   gem "technoweenie-restful-authentication", lib: "restful-authentication", source: "http://gems.github.com/"
@@ -61,7 +61,7 @@ module Rails
         end
       end
 
-      # Add the given source to Gemfile
+      # Add the given source to +Gemfile+
       #
       #   add_source "http://gems.github.com/"
       def add_source(source, options={})
@@ -72,10 +72,10 @@ module Rails
         end
       end
 
-      # Adds a line inside the Application class for config/application.rb.
+      # Adds a line inside the Application class for <tt>config/application.rb</tt>.
       #
-      # If options :env is specified, the line is appended to the corresponding
-      # file in config/environments.
+      # If options <tt>:env</tt> is specified, the line is appended to the corresponding
+      # file in <tt>config/environments</tt>.
       #
       #   environment do
       #     "config.autoload_paths += %W(#{config.root}/extras)"
@@ -116,7 +116,7 @@ module Rails
         end
       end
 
-      # Create a new file in the vendor/ directory. Code can be specified
+      # Create a new file in the <tt>vendor/</tt> directory. Code can be specified
       # in a block or a data string can be given.
       #
       #   vendor("sekrit.rb") do
@@ -143,7 +143,7 @@ module Rails
         create_file("lib/#{filename}", data, verbose: false, &block)
       end
 
-      # Create a new Rakefile with the provided code (either in a block or a string).
+      # Create a new +Rakefile+ with the provided code (either in a block or a string).
       #
       #   rakefile("bootstrap.rake") do
       #     project = ask("What is the UNIX name of your project?")
@@ -213,7 +213,7 @@ module Rails
         in_root { run("#{extify(:capify)} .", verbose: false) }
       end
 
-      # Make an entry in Rails routing file config/routes.rb
+      # Make an entry in Rails routing file <tt>config/routes.rb</tt>
       #
       #   route "root 'welcome#index'"
       def route(routing_code)
diff --git a/railties/lib/rails/generators/app_base.rb b/railties/lib/rails/generators/app_base.rb
index 2022b4ed3d..4988602aea 100644
--- a/railties/lib/rails/generators/app_base.rb
+++ b/railties/lib/rails/generators/app_base.rb
@@ -14,6 +14,7 @@ module Rails
       DATABASES.concat(JDBC_DATABASES)
 
       attr_accessor :rails_template
+      attr_accessor :app_template
       add_shebang_option!
 
       argument :app_path, type: :string
@@ -26,6 +27,9 @@ module Rails
         class_option :template,           type: :string, aliases: '-m',
                                           desc: "Path to some #{name} template (can be a filesystem path or URL)"
 
+        class_option :app_template,       type: :string, aliases: '-n',
+                                          desc: "Path to some #{name} template (can be a filesystem path or URL)"
+
         class_option :skip_gemfile,       type: :boolean, default: false,
                                           desc: "Don't create a Gemfile"
 
@@ -47,6 +51,9 @@ 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 +116,7 @@ module Rails
           jbuilder_gemfile_entry,
           sdoc_gemfile_entry,
           platform_dependent_gemfile_entry,
+          spring_gemfile_entry,
           @extra_entries].flatten.find_all(&@gem_filter)
       end
 
@@ -118,6 +126,10 @@ module Rails
         }.curry[@gem_filter]
       end
 
+      def remove_gem(name)
+        add_gem_entry_filter { |gem| gem.name != name }
+      end
+
       def builder
         @builder ||= begin
           builder_class = get_builder_class
@@ -158,6 +170,10 @@ module Rails
           @target.send :add_gem_entry_filter, *args, &block
         end
 
+        def remove_gem(*args, &block)
+          @target.send :remove_gem, *args, &block
+        end
+
         def method_missing(name, *args, &block)
           @commands << [name, args, block]
         end
@@ -176,7 +192,8 @@ module Rails
       def apply_rails_template
         @recorder = TemplateRecorder.new self
 
-        apply(rails_template, target: @recorder) if rails_template
+        apply(rails_template, target: self) if rails_template
+        apply(app_template, target: @recorder) if app_template
       rescue Thor::Error, LoadError, Errno::ENOENT => e
         raise Error, "The template [#{rails_template}] could not be loaded. Error: #{e}"
       end
@@ -206,13 +223,18 @@ module Rails
 
       def set_default_accessors!
         self.destination_root = File.expand_path(app_path, destination_root)
-        self.rails_template = case options[:template]
-          when /^https?:\/\//
-            options[:template]
-          when String
-            File.expand_path(options[:template], Dir.pwd)
-          else
-            options[:template]
+        self.rails_template = expand_template options[:template]
+        self.app_template = expand_template options[:app_template]
+      end
+
+      def expand_template(name)
+        case name
+        when /^https?:\/\//
+          name
+        when String
+          File.expand_path(name, Dir.pwd)
+        else
+          name
         end
       end
 
@@ -304,7 +326,7 @@ module Rails
                                     'Use SCSS for stylesheets')
         else
           gems << GemfileEntry.version('sass-rails',
-                                     '~> 4.0.0.rc1',
+                                     '~> 4.0.1',
                                      'Use SCSS for stylesheets')
         end
 
@@ -325,7 +347,7 @@ module Rails
 
       def jbuilder_gemfile_entry
         comment = 'Build JSON APIs with ease. Read more: https://github.com/rails/jbuilder'
-        GemfileEntry.version('jbuilder', '~> 1.2', comment)
+        GemfileEntry.version('jbuilder', '~> 2.0', comment)
       end
 
       def sdoc_gemfile_entry
@@ -365,6 +387,12 @@ 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 +416,22 @@ 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/base.rb b/railties/lib/rails/generators/base.rb
index cf33b13fd8..67bab96a22 100644
--- a/railties/lib/rails/generators/base.rb
+++ b/railties/lib/rails/generators/base.rb
@@ -296,7 +296,7 @@ module Rails
           end
         end
 
-        # Return the default value for the option name given doing a lookup in
+        # Returns the default value for the option name given doing a lookup in
         # Rails::Generators.options.
         def self.default_value_for_option(name, options)
           default_for_option(Rails::Generators.options, name, options, options[:default])
diff --git a/railties/lib/rails/generators/erb.rb b/railties/lib/rails/generators/erb.rb
index 73e986ee7f..cfd77097d5 100644
--- a/railties/lib/rails/generators/erb.rb
+++ b/railties/lib/rails/generators/erb.rb
@@ -5,6 +5,10 @@ module Erb # :nodoc:
     class Base < Rails::Generators::NamedBase #:nodoc:
       protected
 
+      def formats
+        format
+      end
+
       def format
         :html
       end
@@ -13,7 +17,7 @@ module Erb # :nodoc:
         :erb
       end
 
-      def filename_with_extensions(name)
+      def filename_with_extensions(name, format)
         [name, format, handler].compact.join(".")
       end
     end
diff --git a/railties/lib/rails/generators/erb/controller/controller_generator.rb b/railties/lib/rails/generators/erb/controller/controller_generator.rb
index 5f06734ab8..e62aece7c5 100644
--- a/railties/lib/rails/generators/erb/controller/controller_generator.rb
+++ b/railties/lib/rails/generators/erb/controller/controller_generator.rb
@@ -11,8 +11,10 @@ module Erb # :nodoc:
 
         actions.each do |action|
           @action = action
-          @path = File.join(base_path, filename_with_extensions(action))
-          template filename_with_extensions(:view), @path
+          Array(formats).each do |format|
+            @path = File.join(base_path, filename_with_extensions(action, format))
+            template filename_with_extensions(:view, format), @path
+          end
         end
       end
     end
diff --git a/railties/lib/rails/generators/erb/mailer/mailer_generator.rb b/railties/lib/rails/generators/erb/mailer/mailer_generator.rb
index 7bcac30dde..66b17bd10e 100644
--- a/railties/lib/rails/generators/erb/mailer/mailer_generator.rb
+++ b/railties/lib/rails/generators/erb/mailer/mailer_generator.rb
@@ -5,8 +5,8 @@ module Erb # :nodoc:
     class MailerGenerator < ControllerGenerator # :nodoc:
       protected
 
-      def format
-        :text
+      def formats
+        [:text, :html]
       end
     end
   end
diff --git a/railties/lib/rails/generators/erb/mailer/templates/view.html.erb b/railties/lib/rails/generators/erb/mailer/templates/view.html.erb
new file mode 100644
index 0000000000..8bb7c2b768
--- /dev/null
+++ b/railties/lib/rails/generators/erb/mailer/templates/view.html.erb
@@ -0,0 +1,5 @@
+<h1><%= class_name %>#<%= @action %></h1>
+
+<p>
+  <%%= @greeting %>, find me in app/views/<%= @path %>
+</p>
diff --git a/railties/lib/rails/generators/erb/scaffold/scaffold_generator.rb b/railties/lib/rails/generators/erb/scaffold/scaffold_generator.rb
index bacbc2d280..b219f459ac 100644
--- a/railties/lib/rails/generators/erb/scaffold/scaffold_generator.rb
+++ b/railties/lib/rails/generators/erb/scaffold/scaffold_generator.rb
@@ -14,8 +14,10 @@ module Erb # :nodoc:
 
       def copy_view_files
         available_views.each do |view|
-          filename = filename_with_extensions(view)
-          template filename, File.join("app/views", controller_file_path, filename)
+          Array(formats).each do |format|
+            filename = filename_with_extensions(view, format)
+            template filename, File.join("app/views", controller_file_path, filename)
+          end
         end
       end
 
diff --git a/railties/lib/rails/generators/rails/app/app_generator.rb b/railties/lib/rails/generators/rails/app/app_generator.rb
index a2023886cd..d2eca5b2fb 100644
--- a/railties/lib/rails/generators/rails/app/app_generator.rb
+++ b/railties/lib/rails/generators/rails/app/app_generator.rb
@@ -78,6 +78,7 @@ module Rails
         template "routes.rb"
         template "application.rb"
         template "environment.rb"
+        template "secrets.yml"
 
         directory "environments"
         directory "initializers"
@@ -225,18 +226,19 @@ module Rails
         build(:vendor)
       end
 
-      def finish_template
-        build(:leftovers)
-      end
-
       def delete_js_folder_skipping_javascript
         if options[:skip_javascript]
           remove_dir 'app/assets/javascripts'
         end
       end
 
+      def finish_template
+        build(:leftovers)
+      end
+
       public_task :run_bundle
       public_task :replay_template
+      public_task :generate_spring_binstubs
 
     protected
 
diff --git a/railties/lib/rails/generators/rails/app/templates/config/application.rb b/railties/lib/rails/generators/rails/app/templates/config/application.rb
index ac41a0cadb..16fe50bab8 100644
--- a/railties/lib/rails/generators/rails/app/templates/config/application.rb
+++ b/railties/lib/rails/generators/rails/app/templates/config/application.rb
@@ -15,7 +15,7 @@ require "action_mailer/railtie"
 
 # Require the gems listed in Gemfile, including any gems
 # you've limited to :test, :development, or :production.
-Bundler.require(:default, Rails.env)
+Bundler.require(*Rails.groups)
 
 module <%= app_const_base %>
   class Application < Rails::Application
@@ -30,10 +30,5 @@ module <%= app_const_base %>
     # The default locale is :en and all translations from config/locales/*.rb,yml are auto loaded.
     # config.i18n.load_path += Dir[Rails.root.join('my', 'locales', '*.{rb,yml}').to_s]
     # config.i18n.default_locale = :de
-<% if options.skip_sprockets? -%>
-
-    # Disable the asset pipeline.
-    config.assets.enabled = false
-<% end -%>
   end
 end
diff --git a/railties/lib/rails/generators/rails/app/templates/config/databases/frontbase.yml b/railties/lib/rails/generators/rails/app/templates/config/databases/frontbase.yml
index c6dfd50d40..138e3a8664 100644
--- a/railties/lib/rails/generators/rails/app/templates/config/databases/frontbase.yml
+++ b/railties/lib/rails/generators/rails/app/templates/config/databases/frontbase.yml
@@ -23,6 +23,7 @@ test:
   <<: *default
   database: <%= app_name %>_test
 
+# Do not keep production credentials in the repository,
+# instead read the configuration from the environment.
 production:
-  <<: *default
-  database: <%= app_name %>_production
+  url: <%%= ENV["DATABASE_URL"] %>
diff --git a/railties/lib/rails/generators/rails/app/templates/config/databases/ibm_db.yml b/railties/lib/rails/generators/rails/app/templates/config/databases/ibm_db.yml
index fe53cd0ea2..2cdb592eeb 100644
--- a/railties/lib/rails/generators/rails/app/templates/config/databases/ibm_db.yml
+++ b/railties/lib/rails/generators/rails/app/templates/config/databases/ibm_db.yml
@@ -61,6 +61,7 @@ test:
   <<: *default
   database: <%= app_name[0,4] %>_tst
 
+# Do not keep production credentials in the repository,
+# instead read the configuration from the environment.
 production:
-  <<: *default
-  database: <%= app_name[0,8] %>
+  url: <%%= ENV["DATABASE_URL"] %>
diff --git a/railties/lib/rails/generators/rails/app/templates/config/databases/jdbc.yml b/railties/lib/rails/generators/rails/app/templates/config/databases/jdbc.yml
index be1dae332f..cefd30d519 100644
--- a/railties/lib/rails/generators/rails/app/templates/config/databases/jdbc.yml
+++ b/railties/lib/rails/generators/rails/app/templates/config/databases/jdbc.yml
@@ -53,6 +53,7 @@ test:
   <<: *default
   url: jdbc:db://localhost/<%= app_name %>_test
 
+# Do not keep production credentials in the repository,
+# instead read the configuration from the environment.
 production:
-  <<: *default
-  url: jdbc:db://localhost/<%= app_name %>_production
+  url: <%%= ENV["DATABASE_URL"] %>
diff --git a/railties/lib/rails/generators/rails/app/templates/config/databases/jdbcmysql.yml b/railties/lib/rails/generators/rails/app/templates/config/databases/jdbcmysql.yml
index 26e2a5976c..d31761349c 100644
--- a/railties/lib/rails/generators/rails/app/templates/config/databases/jdbcmysql.yml
+++ b/railties/lib/rails/generators/rails/app/templates/config/databases/jdbcmysql.yml
@@ -26,6 +26,6 @@ test:
   <<: *default
   database: <%= app_name %>_test
 
-production:
-  <<: *default
-  database: <%= app_name %>_production
+# Do not keep production credentials in the repository,
+# instead read the configuration from the environment.
+production: <%%= ENV["DATABASE_URL"] %>
diff --git a/railties/lib/rails/generators/rails/app/templates/config/databases/jdbcpostgresql.yml b/railties/lib/rails/generators/rails/app/templates/config/databases/jdbcpostgresql.yml
index ccd44cf54b..0d248dc197 100644
--- a/railties/lib/rails/generators/rails/app/templates/config/databases/jdbcpostgresql.yml
+++ b/railties/lib/rails/generators/rails/app/templates/config/databases/jdbcpostgresql.yml
@@ -6,13 +6,20 @@
 default: &default
   adapter: postgresql
   encoding: unicode
-  username: <%= app_name %>
-  password:
 
 development:
   <<: *default
   database: <%= app_name %>_development
 
+  # The specified database role being used to connect to postgres.
+  # To create additional roles in postgres see `$ createuser --help`.
+  # When left blank, postgres will use the default role. This is
+  # the same name as the operating system user that initialized the database.
+  #username: <%= app_name %>
+
+  # The password associated with the postgres role (username).
+  #password:
+
   # Connect on a TCP socket. Omitted by default since the client uses a
   # domain socket that doesn't need configuration. Windows does not have
   # domain sockets, so uncomment these lines.
@@ -35,6 +42,7 @@ test:
   <<: *default
   database: <%= app_name %>_test
 
+# Do not keep production credentials in the repository,
+# instead read the configuration from the environment.
 production:
-  <<: *default
-  database: <%= app_name %>_production
+  url: <%%= ENV["DATABASE_URL"] %>
diff --git a/railties/lib/rails/generators/rails/app/templates/config/databases/jdbcsqlite3.yml b/railties/lib/rails/generators/rails/app/templates/config/databases/jdbcsqlite3.yml
index 28c36eb82f..66eba3bf0d 100644
--- a/railties/lib/rails/generators/rails/app/templates/config/databases/jdbcsqlite3.yml
+++ b/railties/lib/rails/generators/rails/app/templates/config/databases/jdbcsqlite3.yml
@@ -18,6 +18,7 @@ test:
   <<: *default
   database: db/test.sqlite3
 
+# Do not keep production credentials in the repository,
+# instead read the configuration from the environment.
 production:
-  <<: *default
-  database: db/production.sqlite3
+  url: <%%= ENV["DATABASE_URL"] %>
diff --git a/railties/lib/rails/generators/rails/app/templates/config/databases/mysql.yml b/railties/lib/rails/generators/rails/app/templates/config/databases/mysql.yml
index 3fc7ce28a1..d618fc28a6 100644
--- a/railties/lib/rails/generators/rails/app/templates/config/databases/mysql.yml
+++ b/railties/lib/rails/generators/rails/app/templates/config/databases/mysql.yml
@@ -1,4 +1,4 @@
-# MySQL.  Versions 4.1 and 5.0 are recommended.
+# MySQL.  Versions 5.0+ are recommended.
 #
 # Install the MYSQL driver
 #   gem install mysql2
@@ -32,6 +32,11 @@ test:
   <<: *default
   database: <%= app_name %>_test
 
+# Avoid production credentials in the repository,
+# instead read the configuration from the environment.
+#
+# Example:
+#   mysql2://myuser:mypass@localhost/somedatabase
+#
 production:
-  <<: *default
-  database: <%= app_name %>_production
+  url: <%%= ENV["DATABASE_URL"] %>
diff --git a/railties/lib/rails/generators/rails/app/templates/config/databases/oracle.yml b/railties/lib/rails/generators/rails/app/templates/config/databases/oracle.yml
index d5b52c969b..d469ec0f99 100644
--- a/railties/lib/rails/generators/rails/app/templates/config/databases/oracle.yml
+++ b/railties/lib/rails/generators/rails/app/templates/config/databases/oracle.yml
@@ -32,6 +32,7 @@ test:
   <<: *default
   database: <%= app_name %>_test
 
+# Do not keep production credentials in the repository,
+# instead read the configuration from the environment.
 production:
-  <<: *default
-  database: <%= app_name %>_production
+  url: <%%= ENV["DATABASE_URL"] %>
diff --git a/railties/lib/rails/generators/rails/app/templates/config/databases/postgresql.yml b/railties/lib/rails/generators/rails/app/templates/config/databases/postgresql.yml
index eaeb82bddd..93f48656b2 100644
--- a/railties/lib/rails/generators/rails/app/templates/config/databases/postgresql.yml
+++ b/railties/lib/rails/generators/rails/app/templates/config/databases/postgresql.yml
@@ -17,16 +17,23 @@
 default: &default
   adapter: postgresql
   encoding: unicode
-  # For details on connection pooling, see rails configration guide
+  # For details on connection pooling, see rails configuration guide
   # http://guides.rubyonrails.org/configuring.html#database-pooling
   pool: 5
-  username: <%= app_name %>
-  password:
 
 development:
   <<: *default
   database: <%= app_name %>_development
 
+  # The specified database role being used to connect to postgres.
+  # To create additional roles in postgres see `$ createuser --help`.
+  # When left blank, postgres will use the default role. This is
+  # the same name as the operating system user that initialized the database.
+  #username: <%= app_name %>
+
+  # The password associated with the postgres role (username).
+  #password:
+
   # Connect on a TCP socket. Omitted by default since the client uses a
   # domain socket that doesn't need configuration. Windows does not have
   # domain sockets, so uncomment these lines.
@@ -52,6 +59,11 @@ test:
   <<: *default
   database: <%= app_name %>_test
 
+# Do not keep production credentials in the repository,
+# instead read the configuration from the environment.
+#
+# Example:
+#   postgres://myuser:mypass@localhost/somedatabase
+#
 production:
-  <<: *default
-  database: <%= app_name %>_production
+  url: <%%= ENV["DATABASE_URL"] %>
diff --git a/railties/lib/rails/generators/rails/app/templates/config/databases/sqlite3.yml b/railties/lib/rails/generators/rails/app/templates/config/databases/sqlite3.yml
index 1c1a37ca8d..7312ddb6cd 100644
--- a/railties/lib/rails/generators/rails/app/templates/config/databases/sqlite3.yml
+++ b/railties/lib/rails/generators/rails/app/templates/config/databases/sqlite3.yml
@@ -20,6 +20,11 @@ test:
   <<: *default
   database: db/test.sqlite3
 
+# Do not keep production credentials in the repository,
+# instead read the configuration from the environment.
+#
+# Example:
+#   sqlite3://myuser:mypass@localhost/full/path/to/somedatabase
+#
 production:
-  <<: *default
-  database: db/production.sqlite3
+  url: <%%= ENV["DATABASE_URL"] %>
diff --git a/railties/lib/rails/generators/rails/app/templates/config/databases/sqlserver.yml b/railties/lib/rails/generators/rails/app/templates/config/databases/sqlserver.yml
index 4855f66c0d..aa960e493e 100644
--- a/railties/lib/rails/generators/rails/app/templates/config/databases/sqlserver.yml
+++ b/railties/lib/rails/generators/rails/app/templates/config/databases/sqlserver.yml
@@ -42,6 +42,7 @@ test:
   <<: *default
   database: <%= app_name %>_test
 
+# Do not keep production credentials in the repository,
+# instead read the configuration from the environment.
 production:
-  <<: *default
-  database: <%= app_name %>_production
+  url: <%%= ENV["DATABASE_URL"] %>
diff --git a/railties/lib/rails/generators/rails/app/templates/config/environments/development.rb.tt b/railties/lib/rails/generators/rails/app/templates/config/environments/development.rb.tt
index b724d468a2..cce4743a33 100644
--- a/railties/lib/rails/generators/rails/app/templates/config/environments/development.rb.tt
+++ b/railties/lib/rails/generators/rails/app/templates/config/environments/development.rb.tt
@@ -29,5 +29,10 @@ Rails.application.configure do
   # This option may cause significant delays in view rendering with a large
   # number of complex assets.
   config.assets.debug = true
+
+  # Adds additional error checking when serving assets at runtime.
+  # Checks for improperly declared sprockets dependencies.
+  # Raises helpful error messages.
+  config.assets.raise_runtime_errors = true
   <%- end -%>
 end
diff --git a/railties/lib/rails/generators/rails/app/templates/config/environments/production.rb.tt b/railties/lib/rails/generators/rails/app/templates/config/environments/production.rb.tt
index 1dfc9f136b..3baa382bd6 100644
--- a/railties/lib/rails/generators/rails/app/templates/config/environments/production.rb.tt
+++ b/railties/lib/rails/generators/rails/app/templates/config/environments/production.rb.tt
@@ -70,7 +70,7 @@ Rails.application.configure do
   # config.action_mailer.raise_delivery_errors = false
 
   # Enable locale fallbacks for I18n (makes lookups for any locale fall back to
-  # the I18n.default_locale when a translation can not be found).
+  # the I18n.default_locale when a translation cannot be found).
   config.i18n.fallbacks = true
 
   # Send deprecation notices to registered listeners.
diff --git a/railties/lib/rails/generators/rails/app/templates/config/initializers/secret_token.rb.tt b/railties/lib/rails/generators/rails/app/templates/config/secrets.yml
index f3cc6098a3..6e2c45e119 100644
--- a/railties/lib/rails/generators/rails/app/templates/config/initializers/secret_token.rb.tt
+++ b/railties/lib/rails/generators/rails/app/templates/config/secrets.yml
@@ -7,6 +7,16 @@
 # no regular words or you'll be exposed to dictionary attacks.
 # You can use `rake secret` to generate a secure secret key.
 
-# Make sure your secret_key_base is kept private
+# Make sure the secrets in this file are kept private
 # if you're sharing your code publicly.
-Rails.application.config.secret_key_base = '<%= app_secret %>'
+
+development:
+  secret_key_base: <%= app_secret %>
+
+test:
+  secret_key_base: <%= app_secret %>
+
+# Do not keep production secrets in the repository,
+# instead read values from the environment.
+production:
+  secret_key_base: <%%= ENV["RAILS_SECRET_KEY_BASE"] %>
diff --git a/railties/lib/rails/generators/rails/app/templates/test/test_helper.rb b/railties/lib/rails/generators/rails/app/templates/test/test_helper.rb
index 4fd060341e..4ade1a0bdc 100644
--- a/railties/lib/rails/generators/rails/app/templates/test/test_helper.rb
+++ b/railties/lib/rails/generators/rails/app/templates/test/test_helper.rb
@@ -4,8 +4,6 @@ require 'rails/test_help'
 
 class ActiveSupport::TestCase
 <% unless options[:skip_active_record] -%>
-  ActiveRecord::Migration.check_pending!
-
   # Setup all fixtures in test/fixtures/*.yml for all tests in alphabetical order.
   #
   # Note: You'll currently still have to declare fixtures explicitly in integration tests
diff --git a/railties/lib/rails/generators/rails/plugin/templates/Gemfile b/railties/lib/rails/generators/rails/plugin/templates/Gemfile
index d576784415..88ec4e6354 100644
--- a/railties/lib/rails/generators/rails/plugin/templates/Gemfile
+++ b/railties/lib/rails/generators/rails/plugin/templates/Gemfile
@@ -39,5 +39,7 @@ end
 <% end -%>
 
 <% end -%>
+<% unless defined?(JRUBY_VERSION) -%>
 # To use debugger
 # gem 'debugger'
+<% end -%>
diff --git a/railties/lib/rails/generators/rails/resource_route/resource_route_generator.rb b/railties/lib/rails/generators/rails/resource_route/resource_route_generator.rb
index a0e5553e44..e4a2bc2b0f 100644
--- a/railties/lib/rails/generators/rails/resource_route/resource_route_generator.rb
+++ b/railties/lib/rails/generators/rails/resource_route/resource_route_generator.rb
@@ -9,7 +9,7 @@ module Rails
       # should give you
       #
       #   namespace :admin do
-      #     namespace :users
+      #     namespace :users do
       #       resources :products
       #     end
       #   end
diff --git a/railties/lib/rails/generators/test_unit/mailer/mailer_generator.rb b/railties/lib/rails/generators/test_unit/mailer/mailer_generator.rb
index 3334b189bf..85dee1a066 100644
--- a/railties/lib/rails/generators/test_unit/mailer/mailer_generator.rb
+++ b/railties/lib/rails/generators/test_unit/mailer/mailer_generator.rb
@@ -4,11 +4,18 @@ module TestUnit # :nodoc:
   module Generators # :nodoc:
     class MailerGenerator < Base # :nodoc:
       argument :actions, type: :array, default: [], banner: "method method"
-      check_class_collision suffix: "Test"
+
+      def check_class_collision
+        class_collisions "#{class_name}Test", "#{class_name}Preview"
+      end
 
       def create_test_files
         template "functional_test.rb", File.join('test/mailers', class_path, "#{file_name}_test.rb")
       end
+
+      def create_preview_files
+        template "preview.rb", File.join('test/mailers/previews', class_path, "#{file_name}_preview.rb")
+      end
     end
   end
 end
diff --git a/railties/lib/rails/generators/test_unit/mailer/templates/preview.rb b/railties/lib/rails/generators/test_unit/mailer/templates/preview.rb
new file mode 100644
index 0000000000..3bfd5426e8
--- /dev/null
+++ b/railties/lib/rails/generators/test_unit/mailer/templates/preview.rb
@@ -0,0 +1,13 @@
+<% module_namespacing do -%>
+# Preview all emails at http://localhost:3000/rails/mailers/<%= file_path %>
+class <%= class_name %>Preview < ActionMailer::Preview
+<% actions.each do |action| -%>
+
+  # Preview this email at http://localhost:3000/rails/mailers/<%= file_path %>/<%= action %>
+  def <%= action %>
+    <%= class_name %>.<%= action %>
+  end
+<% end -%>
+
+end
+<% end -%>
diff --git a/railties/lib/rails/generators/testing/behaviour.rb b/railties/lib/rails/generators/testing/behaviour.rb
index 7576eba6e0..8e9028a3fb 100644
--- a/railties/lib/rails/generators/testing/behaviour.rb
+++ b/railties/lib/rails/generators/testing/behaviour.rb
@@ -61,9 +61,11 @@ module Rails
         # You can provide a configuration hash as second argument. This method returns the output
         # printed by the generator.
         def run_generator(args=self.default_arguments, config={})
-          capture(:stdout) do
-            args += ['--skip-bundle'] unless args.include? '--dev'
-            self.generator_class.start(args, config.reverse_merge(destination_root: destination_root))
+          without_thor_debug do
+            capture(:stdout) do
+              args += ['--skip-bundle'] unless args.include? '--dev'
+              self.generator_class.start(args, config.reverse_merge(destination_root: destination_root))
+            end
           end
         end
 
@@ -100,6 +102,14 @@ module Rails
             dirname, file_name = File.dirname(absolute), File.basename(absolute).sub(/\.rb$/, '')
             Dir.glob("#{dirname}/[0-9]*_*.rb").grep(/\d+_#{file_name}.rb$/).first
           end
+
+          # TODO: remove this once Bundler 1.5.2 is released
+          def without_thor_debug # :nodoc:
+            thor_debug, ENV['THOR_DEBUG'] = ENV['THOR_DEBUG'], nil
+            yield
+          ensure
+            ENV['THOR_DEBUG'] = thor_debug
+          end
       end
     end
   end