4 files changed, 23 insertions, 4 deletions
diff --git a/railties/CHANGELOG.md b/railties/CHANGELOG.md
index 5a4ad2ff99..f3da431b09 100644
--- a/railties/CHANGELOG.md
+++ b/railties/CHANGELOG.md
@@ -1,3 +1,8 @@
+*   The tasks in the rails task namespace is deprecated in favor of app namespace.
+    (e.g. `rails:update` and `rails:template` tasks is renamed to `app:update` and `app:template`.)
+
+    *Ryo Hashimoto*
+
 *  Enable HSTS with IncludeSudomains header for new applications.
 
    *Egor Homakov*, *Prathamesh Sonpatki*
diff --git a/railties/lib/rails/app_loader.rb b/railties/lib/rails/app_loader.rb
index a9fe21824e..af004d85bf 100644
--- a/railties/lib/rails/app_loader.rb
+++ b/railties/lib/rails/app_loader.rb
@@ -16,7 +16,7 @@ like any other source code, rather than stubs that are generated on demand.
 Here's how to upgrade:
 
   bundle config --delete bin    # Turn off Bundler's stub generator
-  rake rails:update:bin         # Use the new Rails 4 executables
+  rails app:update:bin          # Use the new Rails 5 executables
   git add bin                   # Add bin/ to source control
 
 You may need to remove bin/ from your .gitignore as well.
diff --git a/railties/lib/rails/tasks/framework.rake b/railties/lib/rails/tasks/framework.rake
index 7601836809..ae92836407 100644
--- a/railties/lib/rails/tasks/framework.rake
+++ b/railties/lib/rails/tasks/framework.rake
@@ -1,4 +1,6 @@
-namespace :rails do
+require 'active_support/deprecation'
+
+namespace :app do
   desc "Update configs and some other initially generated files (or use just update:configs or update:bin)"
   task update: [ "update:configs", "update:bin" ]
 
@@ -66,3 +68,15 @@ namespace :rails do
     end
   end
 end
+
+namespace :rails do
+  %i(update template templates:copy update:configs update:bin).each do |task_name|
+    task "#{task_name}" do
+      ActiveSupport::Deprecation.warn(<<-MSG.squish)
+        Running #{task_name} with the rails: namespace is deprecated in favor of app.
+        Run e.g. bin/rails app:#{task_name} instead."
+      MSG
+      Rake.application.invoke_task("app:#{task_name}")
+    end
+  end
+end
diff --git a/railties/test/application/rake_test.rb b/railties/test/application/rake_test.rb
index 3db467256e..92ae3edc08 100644
--- a/railties/test/application/rake_test.rb
+++ b/railties/test/application/rake_test.rb
@@ -369,7 +369,7 @@ module ApplicationTests
 
     def test_copy_templates
       Dir.chdir(app_path) do
-        `bin/rails rails:templates:copy`
+        `bin/rails app:templates:copy`
         %w(controller mailer scaffold).each do |dir|
           assert File.exist?(File.join(app_path, 'lib', 'templates', 'erb', dir))
         end
@@ -384,7 +384,7 @@ module ApplicationTests
       app_file "template.rb", ""
 
       output = Dir.chdir(app_path) do
-        `bin/rails rails:template LOCATION=template.rb`
+        `bin/rails app:template LOCATION=template.rb`
       end
 
       assert_match(/Hello, World!/, output)