invoke

# File railties/lib/rails/generators.rb, line 257
      def invoke(namespace, args = ARGV, config = {})
        names = namespace.to_s.split(":")
        if klass = find_by_namespace(names.pop, names.any? && names.join(":"))
          args << "--help" if args.empty? && klass.arguments.any?(&:required?)
          klass.start(args, config)
          run_after_generate_callback if config[:behavior] == :invoke
        else
          options = sorted_groups.flat_map(&:last)
          error = Command::CorrectableNameError.new("Could not find generator '#{namespace}'.", namespace, options)

          puts <<~MSG
            #{error.detailed_message}
            Run `bin/rails generate --help` for more options.
          MSG
        end
      end

      def add_generated_file(file) # :nodoc:
        (@@generated_files ||= []) << file
        file
      end

      private
        def print_list(base, namespaces) # :doc:
          namespaces = namespaces.reject { |n| hidden_namespaces.include?(n) }
          super
        end

        # Try fallbacks for the given base.
        def invoke_fallbacks_for(name, base)
          return nil unless base && fallbacks[base.to_sym]
          invoked_fallbacks = []

          Array(fallbacks[base.to_sym]).each do |fallback|
            next if invoked_fallbacks.include?(fallback)
            invoked_fallbacks << fallback

            klass = find_by_namespace(name, fallback)
            return klass if klass
          end

          nil
        end

        def command_type # :doc:
          @command_type ||= "generator"
        end

        def lookup_paths # :doc:
          @lookup_paths ||= %( rails/generators generators )
        end

        def file_lookup_paths # :doc:
          @file_lookup_paths ||= [ "{#{lookup_paths.join(',')}}", "**", "*_generator.rb" ]
        end

        def run_after_generate_callback
          if defined?(@@generated_files) && !@@generated_files.empty?
            @after_generate_callbacks.each do |callback|
              callback.call(@@generated_files)
            end
            @@generated_files = []
          end
        end
    end