diff --git a/railties/lib/rails/generators/test_case.rb b/railties/lib/rails/generators/test_case.rb
index 6b97c69d8d9c1ded0a281492cdabfe9047e0131a..24b57aabf92c5c3bb626b92951447ecba2dc4d07 100644
--- a/railties/lib/rails/generators/test_case.rb
+++ b/railties/lib/rails/generators/test_case.rb
@@ -189,6 +189,18 @@ def assert_instance_method(method, content)
       end
       alias :assert_method :assert_instance_method
 
+      # Asserts the given field name gets translated to an attribute type 
+      # properly.
+      #
+      #   assert_attribute_type 'date', :date_select
+      #
+      def assert_attribute_type(name, attribute_type)
+        assert_equal(
+          Rails::Generators::GeneratedAttribute.new('test', name).field_type,
+          attribute_type
+        )
+      end
+      
       # Runs the generator configured for this class. The first argument is an array like
       # command line arguments:
       #
diff --git a/railties/test/generators/generated_attribute_test.rb b/railties/test/generators/generated_attribute_test.rb
new file mode 100644
index 0000000000000000000000000000000000000000..ccd0c6590537656a7ca95f6e00e1852fae1fd7f9
--- /dev/null
+++ b/railties/test/generators/generated_attribute_test.rb
@@ -0,0 +1,40 @@
+require 'generators/generators_test_helper'
+require 'rails/generators/generated_attribute'
+
+class GeneratedAttributeTest < Rails::Generators::TestCase
+  include GeneratorsTestHelper
+
+  def test_field_type_returns_text_field
+    %w(integer float decimal string).each do |name|
+      assert_attribute_type name, :text_field
+    end
+  end
+
+  def test_field_type_returns_datetime_select
+    %w(datetime timestamp).each do |name|
+      assert_attribute_type name, :datetime_select
+    end
+  end
+
+  def test_field_type_returns_time_select
+    assert_attribute_type 'time', :time_select
+  end
+
+  def test_field_type_returns_date_select
+    assert_attribute_type 'date', :date_select
+  end
+
+  def test_field_type_returns_text_area
+    assert_attribute_type 'text', :text_area
+  end
+
+  def test_field_type_returns_check_box
+    assert_attribute_type 'boolean', :check_box
+  end
+
+  def test_field_type_with_unknown_type_returns_text_field
+    %w(foo bar baz).each do |name|
+      assert_attribute_type name, :text_field
+    end
+  end
+end