1 files changed, 12 insertions, 2 deletions
diff --git a/tests/hazmat/primitives/test_hmac.py b/tests/hazmat/primitives/test_hmac.py
index 992bcb1a..124c4377 100644
--- a/tests/hazmat/primitives/test_hmac.py
+++ b/tests/hazmat/primitives/test_hmac.py
@@ -19,12 +19,18 @@ import pytest
 
 import six
 
-from cryptography.exceptions import AlreadyFinalized
-from cryptography.hazmat.primitives import hashes, hmac
+from cryptography import utils
+from cryptography.exceptions import AlreadyFinalized, UnsupportedAlgorithm
+from cryptography.hazmat.primitives import hashes, hmac, interfaces
 
 from .utils import generate_base_hmac_test
 
 
+@utils.register_interface(interfaces.HashAlgorithm)
+class UnsupportedDummyHash(object):
+        name = "unsupported-dummy-hash"
+
+
 class TestHMAC(object):
     test_copy = generate_base_hmac_test(
         hashes.MD5(),
@@ -63,3 +69,7 @@ class TestHMAC(object):
 
         with pytest.raises(AlreadyFinalized):
             h.finalize()
+
+    def test_unsupported_hash(self, backend):
+        with pytest.raises(UnsupportedAlgorithm):
+            hmac.HMAC(b"key", UnsupportedDummyHash(), backend)