Add config.generators.fallbacks.

railties/lib/rails/configuration.rb

@@ -88,11 +88,12 @@ module Rails
     end
 
     class Generators #:nodoc:
-      attr_accessor :aliases, :options, :colorize_logging
+      attr_accessor :aliases, :options, :fallbacks, :colorize_logging
 
       def initialize
         @aliases = Hash.new { |h,k| h[k] = {} }
         @options = Hash.new { |h,k| h[k] = {} }
+        @fallbacks = {}
         @colorize_logging = true
       end
 

railties/lib/rails/generators.rb

@@ -67,6 +67,7 @@ module Rails
       no_color! unless config.colorize_logging
       aliases.deep_merge! config.aliases
       options.deep_merge! config.options
+      fallbacks.merge! config.fallbacks
     end
 
     def self.aliases #:nodoc:

railties/test/application/generators_test.rb

@@ -30,6 +30,7 @@ module ApplicationTests
         assert_equal(true, c.generators.colorize_logging)
         assert_equal({}, c.generators.aliases)
         assert_equal({}, c.generators.options)
+        assert_equal({}, c.generators.fallbacks)
       end
     end
 
@@ -51,11 +52,20 @@ module ApplicationTests
       end
     end
 
-    test "generators aliases and options on initialization" do
+    test "generators set rails fallbacks" do
+      with_config do |c|
+        c.generators.fallbacks[:shoulda] = :test_unit
+        expected = { :shoulda => :test_unit }
+        assert_equal expected, c.generators.fallbacks
+      end
+    end
+
+    test "generators aliases, options and fallbacks on initialization" do
       add_to_config <<-RUBY
         config.generators.rails :aliases => { :test_framework => "-w" }
         config.generators.orm :datamapper
         config.generators.test_framework :rspec
+        config.generators.fallbacks[:shoulda] = :test_unit
       RUBY
 
       # Initialize the application
@@ -65,6 +75,7 @@ module ApplicationTests
 
       assert_equal :rspec, Rails::Generators.options[:rails][:test_framework]
       assert_equal "-w", Rails::Generators.aliases[:rails][:test_framework]
+      assert_equal :test_unit, Rails::Generators.fallbacks[:shoulda]
     end
 
     test "generators no color on initialization" do