lib/roda.rb in roda-3.28.0 vs lib/roda.rb in roda-3.29.0

@@ -267,9 +267,10 @@
         #   Roda.plugin PluginModule
         #   Roda.plugin :csrf
         def plugin(plugin, *args, &block)
           raise RodaError, "Cannot add a plugin to a frozen Roda class" if frozen?
           plugin = RodaPlugins.load_plugin(plugin) if plugin.is_a?(Symbol)
+          raise RodaError, "Invalid plugin type: #{plugin.class.inspect}" unless plugin.is_a?(Module)
           plugin.load_dependencies(self, *args, &block) if plugin.respond_to?(:load_dependencies)
           include(plugin::InstanceMethods) if defined?(plugin::InstanceMethods)
           extend(plugin::ClassMethods) if defined?(plugin::ClassMethods)
           self::RodaRequest.send(:include, plugin::RequestMethods) if defined?(plugin::RequestMethods)
           self::RodaRequest.extend(plugin::RequestClassMethods) if defined?(plugin::RequestClassMethods)