1 files changed, 18 insertions, 0 deletions
diff --git a/activesupport/test/test_test.rb b/activesupport/test/test_test.rb
index 26a45af255..dd1bc8d623 100644
--- a/activesupport/test/test_test.rb
+++ b/activesupport/test/test_test.rb
@@ -60,6 +60,24 @@ class AssertDifferenceTest < Test::Unit::TestCase
         @object.increment
       end
     end
+
+    def test_array_of_expressions_identify_failure
+      assert_difference ['@object.num', '1 + 1'] do
+        @object.increment
+      end
+      fail 'should not get to here'
+    rescue Test::Unit::AssertionFailedError => e
+      assert_equal "<1 + 1> was expression that failed.\n<3> expected but was\n<2>.", e.message
+    end
+
+    def test_array_of_expressions_identify_failure_when_message_provided
+      assert_difference ['@object.num', '1 + 1'], 1, 'something went wrong' do
+        @object.increment
+      end
+      fail 'should not get to here'
+    rescue Test::Unit::AssertionFailedError => e
+      assert_equal "something went wrong.\n<1 + 1> was expression that failed.\n<3> expected but was\n<2>.", e.message
+    end
   else
     def default_test; end
   end