Add `app:update` task to engines

Occasionally we update the file generated by engine.
Therefore, I think that there is a task for updating as well as
application in the engine, it is convenient for updating.

1 files changed, 16 insertions, 0 deletions

diff --git a/railties/test/generators/plugin_generator_test.rb b/railties/test/generators/plugin_generator_test.rb
index 8ec096e5c6..afb37b6a99 100644
--- a/railties/test/generators/plugin_generator_test.rb
+++ b/railties/test/generators/plugin_generator_test.rb
@@ -1,6 +1,7 @@
 require "generators/generators_test_helper"
 require "rails/generators/rails/plugin/plugin_generator"
 require "generators/shared_generator_tests"
+require "rails/engine/updater"
 
 DEFAULT_PLUGIN_FILES = %w(
   .gitignore
@@ -731,6 +732,21 @@ class PluginGeneratorTest < Rails::Generators::TestCase
     end
   end
 
+  def test_app_update_generates_bin_file
+    run_generator [destination_root, "--mountable"]
+
+    Object.const_set("ENGINE_ROOT", destination_root)
+    FileUtils.rm("#{destination_root}/bin/rails")
+
+    quietly { Rails::Engine::Updater.run(:create_bin_files) }
+
+    assert_file "#{destination_root}/bin/rails" do |content|
+      assert_match(%r|APP_PATH = File\.expand_path\('\.\./\.\./test/dummy/config/application', __FILE__\)|, content)
+    end
+  ensure
+    Object.send(:remove_const, "ENGINE_ROOT")
+  end
+
   private
 
     def action(*args, &block)