Merge pull request #23078 from y-yagi/add_application_mailer_rb_to_mountable_engine

add application_mailer.rb to template of mountable engine

railties/lib/rails/generators/rails/plugin/plugin_generator.rb

@@ -337,7 +337,7 @@ def modules
       end
 
       def wrap_in_modules(unwrapped_code)
-        unwrapped_code = "#{unwrapped_code}".strip.gsub(/\W$\n/, '')
+        unwrapped_code = "#{unwrapped_code}".strip.gsub(/\s$\n/, '')
         modules.reverse.inject(unwrapped_code) do |content, mod|
           str = "module #{mod}\n"
           str += content.lines.map { |line| "  #{line}" }.join

railties/lib/rails/generators/rails/plugin/templates/app/mailers/%namespaced_name%/application_mailer.rb.tt

+<%= wrap_in_modules <<-rb.strip_heredoc
+  class ApplicationMailer < ActionMailer::Base
+    default from: 'from@example.com'
+    layout 'mailer'
+  end
+rb
+%>

railties/test/generators/plugin_generator_test.rb

@@ -309,6 +309,7 @@ def test_create_mountable_application_with_mountable_option
     assert_file "app/controllers/bukkits/application_controller.rb", /module Bukkits\n  class ApplicationController < ActionController::Base/
     assert_file "app/models/bukkits/application_record.rb", /module Bukkits\n  class ApplicationRecord < ActiveRecord::Base/
     assert_file "app/jobs/bukkits/application_job.rb", /module Bukkits\n  class ApplicationJob < ActiveJob::Base/
+    assert_file "app/mailers/bukkits/application_mailer.rb", /module Bukkits\n  class ApplicationMailer < ActionMailer::Base\n    default from: 'from@example.com'\n    layout 'mailer'\n/
     assert_file "app/helpers/bukkits/application_helper.rb", /module Bukkits\n  module ApplicationHelper/
     assert_file "app/views/layouts/bukkits/application.html.erb" do |contents|
       assert_match "<title>Bukkits</title>", contents
@@ -337,6 +338,7 @@ def test_create_mountable_application_with_mountable_option_and_hypenated_name
     assert_file "hyphenated-name/app/controllers/hyphenated/name/application_controller.rb", /module Hyphenated\n  module Name\n    class ApplicationController < ActionController::Base\n    end\n  end\nend/
     assert_file "hyphenated-name/app/models/hyphenated/name/application_record.rb",          /module Hyphenated\n  module Name\n    class ApplicationRecord < ActiveRecord::Base\n      self\.abstract_class = true\n    end\n  end\nend/
     assert_file "hyphenated-name/app/jobs/hyphenated/name/application_job.rb",               /module Hyphenated\n  module Name\n    class ApplicationJob < ActiveJob::Base/
+    assert_file "hyphenated-name/app/mailers/hyphenated/name/application_mailer.rb",         /module Hyphenated\n  module Name\n    class ApplicationMailer < ActionMailer::Base\n      default from: 'from@example.com'\n      layout 'mailer'\n    end\n  end\nend/
     assert_file "hyphenated-name/app/helpers/hyphenated/name/application_helper.rb",         /module Hyphenated\n  module Name\n    module ApplicationHelper\n    end\n  end\nend/
     assert_file "hyphenated-name/app/views/layouts/hyphenated/name/application.html.erb" do |contents|
       assert_match "<title>Hyphenated name</title>", contents
@@ -358,6 +360,7 @@ def test_create_mountable_application_with_mountable_option_and_hypenated_and_un
     assert_file "my_hyphenated-name/app/controllers/my_hyphenated/name/application_controller.rb", /module MyHyphenated\n  module Name\n    class ApplicationController < ActionController::Base\n    end\n  end\nend/
     assert_file "my_hyphenated-name/app/models/my_hyphenated/name/application_record.rb",          /module MyHyphenated\n  module Name\n    class ApplicationRecord < ActiveRecord::Base\n      self\.abstract_class = true\n    end\n  end\nend/
     assert_file "my_hyphenated-name/app/jobs/my_hyphenated/name/application_job.rb",               /module MyHyphenated\n  module Name\n    class ApplicationJob < ActiveJob::Base/
+    assert_file "my_hyphenated-name/app/mailers/my_hyphenated/name/application_mailer.rb",         /module MyHyphenated\n  module Name\n    class ApplicationMailer < ActionMailer::Base\n      default from: 'from@example.com'\n      layout 'mailer'\n    end\n  end\nend/
     assert_file "my_hyphenated-name/app/helpers/my_hyphenated/name/application_helper.rb",         /module MyHyphenated\n  module Name\n    module ApplicationHelper\n    end\n  end\nend/
     assert_file "my_hyphenated-name/app/views/layouts/my_hyphenated/name/application.html.erb" do |contents|
       assert_match "<title>My hyphenated name</title>", contents
@@ -379,6 +382,7 @@ def test_create_mountable_application_with_mountable_option_and_multiple_hypenat
     assert_file "deep-hyphenated-name/app/controllers/deep/hyphenated/name/application_controller.rb", /module Deep\n  module Hyphenated\n    module Name\n      class ApplicationController < ActionController::Base\n      end\n    end\n  end\nend/
     assert_file "deep-hyphenated-name/app/models/deep/hyphenated/name/application_record.rb",          /module Deep\n  module Hyphenated\n    module Name\n      class ApplicationRecord < ActiveRecord::Base\n        self\.abstract_class = true\n      end\n    end\n  end\nend/
     assert_file "deep-hyphenated-name/app/jobs/deep/hyphenated/name/application_job.rb",               /module Deep\n  module Hyphenated\n    module Name\n      class ApplicationJob < ActiveJob::Base/
+    assert_file "deep-hyphenated-name/app/mailers/deep/hyphenated/name/application_mailer.rb",         /module Deep\n  module Hyphenated\n    module Name\n      class ApplicationMailer < ActionMailer::Base\n        default from: 'from@example.com'\n        layout 'mailer'\n      end\n    end\n  end\nend/
     assert_file "deep-hyphenated-name/app/helpers/deep/hyphenated/name/application_helper.rb",         /module Deep\n  module Hyphenated\n    module Name\n      module ApplicationHelper\n      end\n    end\n  end\nend/
     assert_file "deep-hyphenated-name/app/views/layouts/deep/hyphenated/name/application.html.erb" do |contents|
       assert_match "<title>Deep hyphenated name</title>", contents