1 files changed, 6 insertions, 0 deletions
diff --git a/activemodel/test/cases/errors_test.rb b/activemodel/test/cases/errors_test.rb
index 8cb8f7ba44..a24cac40ad 100644
--- a/activemodel/test/cases/errors_test.rb
+++ b/activemodel/test/cases/errors_test.rb
@@ -27,6 +27,12 @@ class ErrorsTest < ActiveModel::TestCase
     end
   end
 
+  def test_include?
+    errors = ActiveModel::Errors.new(self)
+    errors[:foo] = 'omg'
+    assert errors.include?(:foo), 'errors should include :foo'
+  end
+
   test "should return true if no errors" do
     person = Person.new
     person.errors[:foo]