AppGenerator: allow both 'rake' and 'rails'

This commit comes from the comments made by @matthewd at https://github.com/rails/rails/pull/23795/files#r54469637
and by @rafaelfranca at https://github.com/rails/rails/pull/23795/files#r54609364

The idea is that if you type (for example) "rake db:migrate" in an AppGenerator,
then this should actually invoke `rake db:migrate` on the command line, whereas
if you type "rails_command db:migrate", this should invoke `rails db:migrate`.

Author: claudiob

railties/lib/rails/generators/actions.rb

@@ -207,18 +207,23 @@ def generate(what, *args)
         in_root { run_ruby_script("bin/rails generate #{what} #{argument}", verbose: false) }
       end
 
-      # Runs the supplied rake task
+      # Runs the supplied rake task (invoked with 'rake ...')
       #
       #   rake("db:migrate")
       #   rake("db:migrate", env: "production")
       #   rake("gems:install", sudo: true)
       def rake(command, options={})
-        log :rake, command
-        env  = options[:env] || ENV["RAILS_ENV"] || 'development'
-        sudo = options[:sudo] && RbConfig::CONFIG['host_os'] !~ /mswin|mingw/ ? 'sudo ' : ''
-        in_root { run("#{sudo}#{extify(:rails)} #{command} RAILS_ENV=#{env}", verbose: false) }
+        execute_command :rake, command, options
+      end
+
+      # Runs the supplied rake task (invoked with 'rails ...')
+      #
+      #   rails("db:migrate")
+      #   rails("db:migrate", env: "production")
+      #   rails("gems:install", sudo: true)
+      def rails_command(command, options={})
+        execute_command :rails, command, options
       end
-      alias :rails_command :rake
 
       # Just run the capify command in root
       #
@@ -271,6 +276,16 @@ def log(*args)
           end
         end
 
+
+        # Runs the supplied command using either "rake ..." or "rails ..."
+        # based on the executor parameter provided.
+        def execute_command(executor, command, options={})
+          log executor, command
+          env  = options[:env] || ENV["RAILS_ENV"] || 'development'
+          sudo = options[:sudo] && RbConfig::CONFIG['host_os'] !~ /mswin|mingw/ ? 'sudo ' : ''
+          in_root { run("#{sudo}#{extify(executor)} #{command} RAILS_ENV=#{env}", verbose: false) }
+        end
+
         # Add an extension to the given name based on the platform.
         def extify(name)
           if RbConfig::CONFIG['host_os'] =~ /mswin|mingw/

railties/test/generators/actions_test.rb

@@ -202,37 +202,37 @@ def test_generate_should_run_script_generate_with_argument_and_options
   end
 
   def test_rails_should_run_rake_command_with_default_env
-    assert_called_with(generator, :run, ["rails log:clear RAILS_ENV=development", verbose: false]) do
+    assert_called_with(generator, :run, ["rake log:clear RAILS_ENV=development", verbose: false]) do
       with_rails_env nil do
         action :rake, 'log:clear'
       end
     end
   end
 
   def test_rails_with_env_option_should_run_rake_command_in_env
-    assert_called_with(generator, :run, ['rails log:clear RAILS_ENV=production', verbose: false]) do
+    assert_called_with(generator, :run, ['rake log:clear RAILS_ENV=production', verbose: false]) do
       action :rake, 'log:clear', env: 'production'
     end
   end
 
   test "rails command with RAILS_ENV variable should run rake command in env" do
-    assert_called_with(generator, :run, ['rails log:clear RAILS_ENV=production', verbose: false]) do
+    assert_called_with(generator, :run, ['rake log:clear RAILS_ENV=production', verbose: false]) do
       with_rails_env "production" do
         action :rake, 'log:clear'
       end
     end
   end
 
   test "env option should win over RAILS_ENV variable when running rake" do
-    assert_called_with(generator, :run, ['rails log:clear RAILS_ENV=production', verbose: false]) do
+    assert_called_with(generator, :run, ['rake log:clear RAILS_ENV=production', verbose: false]) do
       with_rails_env "staging" do
         action :rake, 'log:clear', env: 'production'
       end
     end
   end
 
   test "rails command with sudo option should run rake command with sudo" do
-    assert_called_with(generator, :run, ["sudo rails log:clear RAILS_ENV=development", verbose: false]) do
+    assert_called_with(generator, :run, ["sudo rake log:clear RAILS_ENV=development", verbose: false]) do
       with_rails_env nil do
         action :rake, 'log:clear', sudo: true
       end