diff --git a/letsencrypt/client/tests/client_authenticator_test.py b/letsencrypt/client/tests/client_authenticator_test.py
index 83a7d50d8..c79f26e0a 100644
--- a/letsencrypt/client/tests/client_authenticator_test.py
+++ b/letsencrypt/client/tests/client_authenticator_test.py
@@ -41,6 +41,10 @@ class PerformTest(unittest.TestCase):
         self.assertRaises(
             errors.LetsEncryptClientAuthError, self.auth.perform, [unexpected])
 
+    def test_chall_pref(self):
+        self.assertEqual(
+            self.auth.get_chall_pref("example.com"), ["recoveryToken"])
+
 
 class CleanupTest(unittest.TestCase):
     """Test the Authenticator cleanup function."""
diff --git a/letsencrypt/client/tests/recovery_token_test.py b/letsencrypt/client/tests/recovery_token_test.py
index 94445a798..0a49137d8 100644
--- a/letsencrypt/client/tests/recovery_token_test.py
+++ b/letsencrypt/client/tests/recovery_token_test.py
@@ -42,6 +42,11 @@ class RecoveryTokenTest(unittest.TestCase):
         # Shouldn't throw an error
         self.rec_token.cleanup(challenge_util.RecTokenChall("example4.com"))
 
+        # SHOULD throw an error (OSError other than nonexistent file)
+        self.assertRaises(
+            OSError, self.rec_token.cleanup,
+            challenge_util.RecTokenChall("a"+"r"*10000+".com"))
+
     def test_perform_stored(self):
         self.rec_token.store_token("example4.com", 444)
         response = self.rec_token.perform(