Rename exception type

Thanks @leplatrem for the suggestion.

Author: glasserc

autograph_utils/__init__.py

@@ -169,7 +169,7 @@ def detail(self):
         )
 
 
-class CertificateUnknownPublicKey(BadCertificate):
+class CertificateUnsupportedKeyType(BadCertificate):
     """An internal error indicating that support for some type of key is missing."""
 
     def __init__(self, cert, key):
@@ -415,7 +415,7 @@ def _verify_cert_link(self, current_cert, next_cert):
             except cryptography.exceptions.InvalidSignature:
                 raise CertificateChainBroken(current_cert, next_cert)
         else:
-            raise CertificateUnknownPublicKey(current_cert, key)
+            raise CertificateUnsupportedKeyType(current_cert, key)
 
     def _check_name_constraints(self, current_cert, next_cert):
         try:

tests/test_autograph_utils.py

@@ -321,7 +321,7 @@ async def test_unknown_key(aiohttp_session, mock_with_x5u, cache, now_fixed):
     with mock.patch("cryptography.x509.load_pem_x509_certificate") as load_cert_mock:
         load_cert_mock.side_effect = lambda *args, **kwargs: certs.pop(0)
         s = SignatureVerifier(aiohttp_session, cache, DEV_ROOT_HASH)
-        with pytest.raises(autograph_utils.CertificateUnknownPublicKey) as excinfo:
+        with pytest.raises(autograph_utils.CertificateUnsupportedKeyType) as excinfo:
             await s.verify_x5u(FAKE_CERT_URL)
 
     assert excinfo.value.cert == mock_intermediate