diff --git a/railties/lib/generators/base.rb b/railties/lib/generators/base.rb
index e5e2c03b48..5fa6c72f43 100644
--- a/railties/lib/generators/base.rb
+++ b/railties/lib/generators/base.rb
@@ -3,15 +3,17 @@ require 'generators/actions'
 module Rails
   module Generators
     DEFAULTS = {
-      :orm => 'active_record',
+      :fixture => true,
       :helper => true,
+      :orm => 'active_record',
       :test_framework => 'test_unit',
       :template_engine => 'erb'
     }
 
     ALIASES = {
+      :fixture_replacement => '-r',
+      :helper => '-l',
       :orm => '-o',
-      :helper => '-v',
       :test_framework => '-t',
       :template_engine => '-e'
     }
@@ -70,11 +72,13 @@ module Rails
       #
       #   ruby script/generate controller Account --test-framework=test_unit
       #
-      # The controller generator will then invoke "test_unit:generators:controller".
-      # If it can't be found it then tries to invoke only "test_unit".
+      # The controller generator will then try to invoke the following generators:
       #
-      # This allows any test framework to hook into Rails as long as it
-      # provides a "test_framework:generators:controller" generator.
+      #   "rails:generators:test_unit", "test_unit:generators:controller", "test_unit"
+      #
+      # In this case, the "test_unit:generators:controller" is available and is
+      # invoked. This allows any test framework to hook into Rails as long as it
+      # provides any of the hooks above.
       #
       # Finally, if the user don't want to use any test framework, he can do:
       #
@@ -84,12 +88,35 @@ module Rails
       #
       #   ruby script/generate controller Account --no-test-framework
       #
+      # ==== Another example
+      #
+      # Another example of invoke_for hooks is fixture replacement tools.
+      # Consider this TestUnit model generator:
+      #
+      #   class ModelGenerator < TestUnit::Generators::Base
+      #     invoke_for :fixture_replacement, :aliases => "-r"
+      #   end
+      #
+      # When invoked as:
+      #
+      #   ruby script/generate test_unit:model Account -r fixjour
+      #
+      # It will lookup for any of these generators:
+      #
+      #   "test_unit:generators:fixjour", "fixjour:generators:model", "fixjour"
+      #
+      # Fixjour can choose any of these hooks to implement. For example, if
+      # Fixjour has different output for rspec and test_unit, it will likely
+      # implement the first hook. However if the output is the same for both,
+      # it will implement the second or the third depending on the number of
+      # generators it has.
+      #
       def self.invoke_for(*names)
         default_options = names.extract_options!
 
         names.each do |name|
           options = default_options.dup
-          options[:desc]    ||= "#{name.to_s.humanize} to be used"
+          options[:desc]    ||= "#{name.to_s.humanize} to be invoked"
           options[:banner]  ||= "NAME"
           options[:aliases] ||= ALIASES[name]
 
@@ -100,13 +127,12 @@ module Rails
               return unless options[#{name.inspect}]
 
               klass = Rails::Generators.find_by_namespace(options[#{name.inspect}],
-                                                          nil, self.class.generator_name)
+                                                          self.class.base_name, self.class.generator_name)
 
               if klass
                 invoke klass
               else
-                task = "\#{options[#{name.inspect}]}:generators:\#{self.class.generator_name}"
-                say "Could not find and invoke '\#{task}'."
+                say "Could not find and invoke '\#{options[#{name.inspect}]}'."
               end
             end
           METHOD
@@ -140,11 +166,7 @@ module Rails
         default_options = names.extract_options!
 
         names.each do |name|
-          options = default_options.dup
-          options[:desc] ||= "Indicates when to use #{name.to_s.humanize}"
-
-          # TODO Reverse --name to --skip-name if default is given.
-          class_option name, options.merge!(:type => :boolean, :default => DEFAULTS[name] || false)
+          conditional_class_option name, default_options.dup
 
           class_eval <<-METHOD, __FILE__, __LINE__
             def invoke_if_#{name}
@@ -156,7 +178,7 @@ module Rails
               if klass
                 invoke klass
               else
-                say "Could not find and invoke '#{name.inspect}'."
+                say "Could not find and invoke '#{name}'."
               end
             end
           METHOD
@@ -220,6 +242,14 @@ module Rails
           end
         end
 
+        # Creates a conditional class option with type boolean, default value
+        # lookup and default description.
+        #
+        def self.conditional_class_option(name, options={})
+          options[:desc] ||= "Indicates when to generate #{name.to_s.humanize.downcase}"
+          class_option name, options.merge!(:type => :boolean, :default => DEFAULTS[name] || false)
+        end
+
         # Small macro to add ruby as an option to the generator with proper
         # default value plus an instance helper method called shebang.
         #
diff --git a/railties/lib/generators/test_unit/model/model_generator.rb b/railties/lib/generators/test_unit/model/model_generator.rb
index 901ed70468..6aff027107 100644
--- a/railties/lib/generators/test_unit/model/model_generator.rb
+++ b/railties/lib/generators/test_unit/model/model_generator.rb
@@ -4,18 +4,16 @@ module TestUnit
       argument :attributes, :type => :hash, :default => {}, :banner => "field:type, field:type"
 
       check_class_collision :suffix => "Test"
-
-      # TODO Add DEFAULTS support
-      class_option :skip_fixture, :type => :boolean, :default => false,
-                   :desc => "Don't generate a fixture file"
+      conditional_class_option :fixture
 
       def create_test_file
         template 'unit_test.rb', File.join('test/unit', class_path, "#{file_name}_test.rb")
       end
 
-      # TODO Add fixture replacement support
+      invoke_for :fixture_replacement
+
       def create_fixture_file
-        unless options[:skip_fixture]
+        if options[:fixture] && options[:fixture_replacement].nil?
           template 'fixtures.yml', File.join('test/fixtures', "#{table_name}.yml")
         end
       end
diff --git a/railties/test/generators/helper_generator_test.rb b/railties/test/generators/helper_generator_test.rb
index b2533e5315..41e1e1dce2 100644
--- a/railties/test/generators/helper_generator_test.rb
+++ b/railties/test/generators/helper_generator_test.rb
@@ -20,7 +20,7 @@ class HelperGeneratorTest < GeneratorsTestCase
 
   def test_logs_if_the_test_framework_cannot_be_found
     content = run_generator ["admin", "--test-framework=unknown"]
-    assert_match /Could not find and invoke 'unknown:generators:helper'/, content
+    assert_match /Could not find and invoke 'unknown'/, content
   end
 
   def test_check_class_collision
diff --git a/railties/test/generators/mailer_generator_test.rb b/railties/test/generators/mailer_generator_test.rb
index 3e5dc60361..5d21da3dd1 100644
--- a/railties/test/generators/mailer_generator_test.rb
+++ b/railties/test/generators/mailer_generator_test.rb
@@ -36,7 +36,7 @@ class MailerGeneratorTest < GeneratorsTestCase
 
   def test_logs_if_the_template_engine_cannot_be_found
     content = run_generator ["notifier", "foo", "bar", "--template-engine=unknown"]
-    assert_match /Could not find and invoke 'unknown:generators:mailer'/, content
+    assert_match /Could not find and invoke 'unknown'/, content
   end
 
   def test_actions_are_turned_into_methods
diff --git a/railties/test/generators/model_generator_test.rb b/railties/test/generators/model_generator_test.rb
index 425c4f581a..904f77242d 100644
--- a/railties/test/generators/model_generator_test.rb
+++ b/railties/test/generators/model_generator_test.rb
@@ -22,6 +22,12 @@ class ModelGeneratorTest < GeneratorsTestCase
     assert_no_file "test/fixtures/accounts.yml"
   end
 
+  def test_fixtures_are_skipped_if_fixture_replacement_is_given
+    content = run_generator ["account", "-r", "fixjour"]
+    assert_match /Could not find and invoke 'fixjour'/, content
+    assert_no_file "test/fixtures/accounts.yml"
+  end
+
   def test_check_class_collision
     content = capture(:stderr){ run_generator ["object"] }
     assert_match /The name 'Object' is either already used in your application or reserved/, content
diff --git a/railties/test/generators/observer_generator_test.rb b/railties/test/generators/observer_generator_test.rb
index e2b027028a..3707b70c7e 100644
--- a/railties/test/generators/observer_generator_test.rb
+++ b/railties/test/generators/observer_generator_test.rb
@@ -23,7 +23,7 @@ class ObserverGeneratorTest < GeneratorsTestCase
 
   def test_logs_if_the_test_framework_cannot_be_found
     content = run_generator ["account", "--test-framework=unknown"]
-    assert_match /Could not find and invoke 'unknown:generators:observer'/, content
+    assert_match /Could not find and invoke 'unknown'/, content
   end
 
   protected
diff --git a/railties/test/generators/plugin_generator_test.rb b/railties/test/generators/plugin_generator_test.rb
index 3f2b27c518..9e7b597739 100644
--- a/railties/test/generators/plugin_generator_test.rb
+++ b/railties/test/generators/plugin_generator_test.rb
@@ -27,7 +27,7 @@ class PluginGeneratorTest < GeneratorsTestCase
 
   def test_logs_if_the_test_framework_cannot_be_found
     content = run_generator ["plugin_fu", "--test-framework=unknown"]
-    assert_match /Could not find and invoke 'unknown:generators:plugin'/, content
+    assert_match /Could not find and invoke 'unknown'/, content
   end
 
   def test_creates_tasks_if_required