Enhance PKey.from_path and test it better

5 files changed, 40 insertions, 23 deletions

diff --git a/tests/_support/ed448.key b/tests/_support/ed448.key
new file mode 100644
index 00000000..887b51c6
--- /dev/null
+++ b/tests/_support/ed448.key
@@ -0,0 +1,4 @@
+-----BEGIN PRIVATE KEY-----
+MEcCAQAwBQYDK2VxBDsEOcvcl9IoD0ktR5RWtW84NM7O2e4LmD2cWfRg7Wht/OA9
+POkmRW12VNvlP6BsXKir5yygumIjD91SQQ==
+-----END PRIVATE KEY-----
diff --git a/tests/conftest.py b/tests/conftest.py
index beef87c2..f3dc2d61 100644
--- a/tests/conftest.py
+++ b/tests/conftest.py
@@ -136,7 +136,7 @@ for datum in key_data:
 
 
 @pytest.fixture(scope="session", params=key_data, ids=lambda x: x[0])
-def key(request):
+def keys(request):
     """
     Yield an object for each known type of key, with attributes:
 
diff --git a/tests/pkey.py b/tests/pkey.py
index b1cba825..9c8fe8fc 100644
--- a/tests/pkey.py
+++ b/tests/pkey.py
@@ -1,13 +1,38 @@
-from paramiko import PKey
+from pytest import raises
+
+from cryptography.hazmat.primitives.asymmetric.ed448 import Ed448PrivateKey
+from paramiko import PKey, UnknownKeyType, RSAKey
+
+from ._util import _support
 
 
 class PKey_:
     class from_type_string:
-        def loads_from_type_and_bytes(self, key):
-            obj = PKey.from_type_string(key.full_type, key.pkey.asbytes())
-            assert obj == key.pkey
+        def loads_from_type_and_bytes(self, keys):
+            obj = PKey.from_type_string(keys.full_type, keys.pkey.asbytes())
+            assert obj == keys.pkey
 
     class from_path:
-        def loads_from_file_path(self, key):
-            obj = PKey.from_path(key.path)
-            assert obj == key.pkey
+        def loads_from_Path(self, keys):
+            obj = PKey.from_path(keys.path)
+            assert obj == keys.pkey
+
+        def loads_from_str(self):
+            key = PKey.from_path(str(_support("rsa.key")))
+            assert isinstance(key, RSAKey)
+
+        def raises_UnknownKeyType_for_unknown_types(self):
+            # I.e. a real, becomes a useful object via cryptography.io, key
+            # class that we do NOT support. Chose Ed448 randomly as OpenSSH
+            # doesn't seem to support it either, going by ssh-keygen...
+            keypath = _support("ed448.key")
+            with raises(UnknownKeyType) as exc:
+                PKey.from_path(keypath)
+            assert issubclass(exc.value.key_type, Ed448PrivateKey)
+            with open(keypath, "rb") as fd:
+                assert exc.value.key_bytes == fd.read()
+
+        def leaves_cryptography_exceptions_untouched(self):
+            # a Python file is not a private key!
+            with raises(ValueError):
+                PKey.from_path(__file__)
diff --git a/tests/test_client.py b/tests/test_client.py
index 564cda00..ea7396d9 100644
--- a/tests/test_client.py
+++ b/tests/test_client.py
@@ -194,9 +194,7 @@ class ClientTest(unittest.TestCase):
             run_kwargs[key] = kwargs.pop(key, None)
         # Server setup
         threading.Thread(target=self._run, kwargs=run_kwargs).start()
-        host_key = paramiko.RSAKey.from_private_key_file(
-            _support("rsa.key")
-        )
+        host_key = paramiko.RSAKey.from_private_key_file(_support("rsa.key"))
         public_host_key = paramiko.RSAKey(data=host_key.asbytes())
 
         # Client setup
@@ -415,9 +413,7 @@ class SSHClientTest(ClientTest):
         """
         warnings.filterwarnings("ignore", "tempnam.*")
 
-        host_key = paramiko.RSAKey.from_private_key_file(
-            _support("rsa.key")
-        )
+        host_key = paramiko.RSAKey.from_private_key_file(_support("rsa.key"))
         public_host_key = paramiko.RSAKey(data=host_key.asbytes())
         fd, localname = mkstemp()
         os.close(fd)
@@ -517,9 +513,7 @@ class SSHClientTest(ClientTest):
         """
         # Start the thread with a 1 second wait.
         threading.Thread(target=self._run, kwargs={"delay": 1}).start()
-        host_key = paramiko.RSAKey.from_private_key_file(
-            _support("rsa.key")
-        )
+        host_key = paramiko.RSAKey.from_private_key_file(_support("rsa.key"))
         public_host_key = paramiko.RSAKey(data=host_key.asbytes())
 
         self.tc = SSHClient()
diff --git a/tests/test_pkey.py b/tests/test_pkey.py
index c5b20f91..47e19945 100644
--- a/tests/test_pkey.py
+++ b/tests/test_pkey.py
@@ -138,12 +138,6 @@ TEST_KEY_BYTESTR = "\x00\x00\x00\x07ssh-rsa\x00\x00\x00\x01#\x00\x00\x00\x00ӏV\
 
 
 class KeyTest(unittest.TestCase):
-    def setUp(self):
-        pass
-
-    def tearDown(self):
-        pass
-
     def assert_keyfile_is_encrypted(self, keyfile):
         """
         A quick check that filename looks like an encrypted key.