load_plugin

# File railties/lib/initializer.rb, line 380
      def load_plugin(directory)
        name = File.basename(directory)
        return false if loaded_plugins.include?(name)

        # Catch nonexistent and empty plugins.
        raise LoadError, "No such plugin: #{directory}" unless plugin_path?(directory)

        lib_path  = File.join(directory, 'lib')
        init_path = File.join(directory, 'init.rb')
        has_lib   = File.directory?(lib_path)
        has_init  = File.file?(init_path)

        # Add lib to load path *after* the application lib, to allow
        # application libraries to override plugin libraries.
        if has_lib
          application_lib_index = $LOAD_PATH.index(File.join(RAILS_ROOT, "lib")) || 0
          $LOAD_PATH.insert(application_lib_index + 1, lib_path)
          Dependencies.load_paths << lib_path
          Dependencies.load_once_paths << lib_path
        end

        # Allow plugins to reference the current configuration object
        config = configuration
        
        # Add to set of loaded plugins before 'name' collapsed in eval.
        loaded_plugins << name

        # Evaluate init.rb.
        silence_warnings { eval(IO.read(init_path), binding, init_path) } if has_init

        true
      end