diff --git a/test/unit/repository_cvs_test.rb b/test/unit/repository_cvs_test.rb
index 207121ca2..393945ace 100644
--- a/test/unit/repository_cvs_test.rb
+++ b/test/unit/repository_cvs_test.rb
@@ -148,6 +148,9 @@ class RepositoryCvsTest < ActiveSupport::TestCase
       assert_equal '1.1', ann.revisions[0].revision
       assert_equal 'LANG', ann.revisions[0].author
       assert_equal 'CVS test repository', ann.lines[0]
+
+     # invalid revision
+     assert_nil @repository.annotate('README', '123')
    end
 
   else