TestUnit, you have a home.

railties/bin/gen

@@ -22,7 +22,7 @@ end
 
 name = ARGV.shift
 
-if klass = Thor::Util.find_by_namespace("rails:generators:#{name}")
+if klass = Thor::Util.find_by_namespace("rails:#{name}")
   klass.start
 elsif klass = Thor::Util.find_by_namespace(name)
   klass.start

railties/lib/generators/base.rb

@@ -2,6 +2,7 @@
 
 module Rails
   module Generators
+
     class Error < Thor::Error
     end
 
@@ -12,7 +13,7 @@ class Base < Thor::Group
       # Automatically sets the source root based on the class name.
       #
       def self.source_root
-        @source_root ||= File.expand_path(File.join(File.dirname(__FILE__), 'rails', generator_name, 'templates'))
+        @source_root ||= File.expand_path(File.join(File.dirname(__FILE__), base_name, generator_name, 'templates'))
       end
 
       # Convenience method to get the namespace from the class name.
@@ -21,50 +22,63 @@ def self.namespace(name=nil)
         if name
           super
         else
-          @namespace ||= "rails:generators:#{generator_name}"
+          @namespace ||= "#{base_name}:#{generator_name}"
         end
       end
 
-    protected
+      protected
 
-      # Use Rails default banner.
-      #
-      def self.banner
-        "#{$0} #{generator_name} #{self.arguments.map(&:usage).join(' ')} [options]"
-      end
+        # Use Rails default banner.
+        #
+        def self.banner
+          "#{$0} #{generator_name} #{self.arguments.map(&:usage).join(' ')} [options]"
+        end
 
-      # Removes the namespaces and get the generator name. For example,
-      # Rails::Generators::MetalGenerator will return "metal" as generator name.
-      #
-      # The name is used to set the namespace (in this case "rails:generators:metal")
-      # and to set the source root ("generators/metal/templates").
-      #
-      def self.generator_name
-        @generator_name ||= begin
-          klass_name = self.name.gsub(/^Rails::Generators::/, '')
-          klass_name.gsub!(/Generator$/, '')
-          klass_name.underscore
+        # Sets the base_name. Overwriten by test unit generators.
+        #
+        def self.base_name
+          'rails'
         end
-      end
 
-      # Small macro to add ruby as an option to the generator with proper
-      # default value plus an instance helper method called shebang.
-      #
-      def self.add_shebang_option!
-        require 'rbconfig'
-        default = File.join(Config::CONFIG['bindir'], Config::CONFIG['ruby_install_name'])
+        # Removes the namespaces and get the generator name. For example,
+        # Rails::Generators::MetalGenerator will return "metal" as generator name.
+        #
+        # The name is used to set the namespace (in this case "rails:metal")
+        # and to set the source root ("rails/metal/templates").
+        #
+        def self.generator_name
+          @generator_name ||= begin
+            klass_name = self.name.gsub(/^Rails::Generators::/, '')
+            klass_name.gsub!(/Generator$/, '')
+            klass_name.underscore
+          end
+        end
 
-        class_option :ruby, :type => :string, :aliases => "-r", :default => default,
-                            :desc => "Path to the Ruby binary of your choice"
+        # Small macro to add ruby as an option to the generator with proper
+        # default value plus an instance helper method called shebang.
+        #
+        def self.add_shebang_option!
+          require 'rbconfig'
+          default = File.join(Config::CONFIG['bindir'], Config::CONFIG['ruby_install_name'])
 
-        class_eval do
-          protected
-          def shebang
-            "#!#{options[:ruby] || "/usr/bin/env ruby"}"
+          class_option :ruby, :type => :string, :aliases => "-r", :default => default,
+                              :desc => "Path to the Ruby binary of your choice"
+
+          class_eval do
+            protected
+            def shebang
+              "#!#{options[:ruby] || "/usr/bin/env ruby"}"
+            end
           end
         end
-      end
+    end
 
+    class TestUnit < Base
+      protected
+        def self.base_name
+          'testunit'
+        end
     end
+
   end
 end