Formalize typing for server specifications (#376)

This also drops support for passing None as a server spec, which is
something many tests were doing out of lazy convenience. I can't think
of a reason why we'd want to support that for real world usage.

3 files changed, 31 insertions, 31 deletions

diff --git a/pymemcache/client/base.py b/pymemcache/client/base.py
index d1392d4..bcfce10 100644
--- a/pymemcache/client/base.py
+++ b/pymemcache/client/base.py
@@ -11,9 +11,11 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
+
 import errno
 import platform
 import socket
+from typing import Tuple, Union
 
 from pymemcache import pool
 
@@ -49,6 +51,8 @@ STORE_RESULTS_VALUE = {
     b"EXISTS": False,
 }
 
+ServerSpec = Union[Tuple[str, int], str]
+
 
 # Some of the values returned by the "stats" command
 # need mapping into native Python types
@@ -116,13 +120,11 @@ def check_key_helper(key, allow_unicode_keys, key_prefix=b""):
     return key
 
 
-def normalize_server_spec(server):
-    if isinstance(server, tuple) or server is None:
+def normalize_server_spec(server: ServerSpec) -> ServerSpec:
+    if isinstance(server, tuple):
         return server
-    if isinstance(server, list):
-        return tuple(server)  # Assume [host, port] provided.
     if not isinstance(server, str):
-        raise ValueError("Unknown server provided: %r" % server)
+        raise ValueError(f"Unsupported server specification: {server!r}")
     if server.startswith("unix:"):
         return server[5:]
     if server.startswith("/"):
@@ -130,8 +132,8 @@ def normalize_server_spec(server):
     if ":" not in server or server.endswith("]"):
         host, port = server, 11211
     else:
-        host, port = server.rsplit(":", 1)
-        port = int(port)
+        parts = server.rsplit(":", 1)
+        host, port = parts[0], int(parts[1])
     if host.startswith("["):
         host = host.strip("[]")
     return (host, port)
@@ -267,7 +269,7 @@ class Client:
 
     def __init__(
         self,
-        server,
+        server: ServerSpec,
         serde=None,
         serializer=None,
         deserializer=None,
@@ -376,7 +378,6 @@ class Client:
         if not isinstance(self.server, tuple):
             sockaddr = self.server
             sock = s.socket(s.AF_UNIX, s.SOCK_STREAM)
-
         else:
             sock = None
             error = None
@@ -1191,7 +1192,7 @@ class PooledClient:
 
     def __init__(
         self,
-        server,
+        server: ServerSpec,
         serde=None,
         serializer=None,
         deserializer=None,
diff --git a/pymemcache/test/test_client.py b/pymemcache/test/test_client.py
index 56f3895..421d923 100644
--- a/pymemcache/test/test_client.py
+++ b/pymemcache/test/test_client.py
@@ -178,7 +178,7 @@ class CustomizedClient(Client):
 @pytest.mark.unit()
 class ClientTestMixin:
     def make_client(self, mock_socket_values, **kwargs):
-        client = Client(None, **kwargs)
+        client = Client("localhost", **kwargs)
         # mock out client._connect() rather than hard-setting client.sock to
         # ensure methods are checking whether self.sock is None before
         # attempting to use it
@@ -189,7 +189,7 @@ class ClientTestMixin:
         return client
 
     def make_customized_client(self, mock_socket_values, **kwargs):
-        client = CustomizedClient(None, **kwargs)
+        client = CustomizedClient("localhost", **kwargs)
         # mock out client._connect() rather than hard-setting client.sock to
         # ensure methods are checking whether self.sock is None before
         # attempting to use it
@@ -1290,9 +1290,9 @@ class TestClientSocketConnect(unittest.TestCase):
 
 class TestPooledClient(ClientTestMixin, unittest.TestCase):
     def make_client(self, mock_socket_values, **kwargs):
-        mock_client = Client(None, **kwargs)
+        mock_client = Client("localhost", **kwargs)
         mock_client.sock = MockSocket(list(mock_socket_values))
-        client = PooledClient(None, **kwargs)
+        client = PooledClient("localhost", **kwargs)
         client.client_pool = pool.ObjectPool(lambda: mock_client)
         return client
 
@@ -1360,9 +1360,9 @@ class TestPooledClient(ClientTestMixin, unittest.TestCase):
 
 class TestPooledClientIdleTimeout(ClientTestMixin, unittest.TestCase):
     def make_client(self, mock_socket_values, **kwargs):
-        mock_client = Client(None, **kwargs)
+        mock_client = Client("localhost", **kwargs)
         mock_client.sock = MockSocket(list(mock_socket_values))
-        client = PooledClient(None, pool_idle_timeout=60, **kwargs)
+        client = PooledClient("localhost", pool_idle_timeout=60, **kwargs)
         client.client_pool = pool.ObjectPool(lambda: mock_client)
         return client
 
@@ -1392,7 +1392,7 @@ class TestPooledClientIdleTimeout(ClientTestMixin, unittest.TestCase):
 
 class TestMockClient(ClientTestMixin, unittest.TestCase):
     def make_client(self, mock_socket_values, **kwargs):
-        client = MockMemcacheClient(None, **kwargs)
+        client = MockMemcacheClient("localhost", **kwargs)
         client.sock = MockSocket(list(mock_socket_values))
         return client
 
@@ -1440,7 +1440,7 @@ class TestMockClient(ClientTestMixin, unittest.TestCase):
 
 class TestPrefixedClient(ClientTestMixin, unittest.TestCase):
     def make_client(self, mock_socket_values, **kwargs):
-        client = Client(None, key_prefix=b"xyz:", **kwargs)
+        client = Client("localhost", key_prefix=b"xyz:", **kwargs)
         client.sock = MockSocket(list(mock_socket_values))
         return client
 
@@ -1487,9 +1487,9 @@ class TestPrefixedClient(ClientTestMixin, unittest.TestCase):
 
 class TestPrefixedPooledClient(TestPrefixedClient):
     def make_client(self, mock_socket_values, **kwargs):
-        mock_client = Client(None, key_prefix=b"xyz:", **kwargs)
+        mock_client = Client("localhost", key_prefix=b"xyz:", **kwargs)
         mock_client.sock = MockSocket(list(mock_socket_values))
-        client = PooledClient(None, key_prefix=b"xyz:", **kwargs)
+        client = PooledClient("localhost", key_prefix=b"xyz:", **kwargs)
         client.client_pool = pool.ObjectPool(lambda: mock_client)
         return client
 
@@ -1497,7 +1497,7 @@ class TestPrefixedPooledClient(TestPrefixedClient):
 @pytest.mark.unit()
 class TestRetryOnEINTR(unittest.TestCase):
     def make_client(self, values):
-        client = Client(None)
+        client = Client("localhost")
         client.sock = MockSocket(list(values))
         return client
 
@@ -1518,9 +1518,7 @@ class TestRetryOnEINTR(unittest.TestCase):
 class TestNormalizeServerSpec(unittest.TestCase):
     def test_normalize_server_spec(self):
         f = normalize_server_spec
-        assert f(None) is None
         assert f(("127.0.0.1", 12345)) == ("127.0.0.1", 12345)
-        assert f(["127.0.0.1", 12345]) == ("127.0.0.1", 12345)
         assert f("unix:/run/memcached/socket") == "/run/memcached/socket"
         assert f("/run/memcached/socket") == "/run/memcached/socket"
         assert f("localhost") == ("localhost", 11211)
@@ -1530,13 +1528,14 @@ class TestNormalizeServerSpec(unittest.TestCase):
         assert f("127.0.0.1") == ("127.0.0.1", 11211)
         assert f("127.0.0.1:12345") == ("127.0.0.1", 12345)
 
-        with pytest.raises(ValueError) as excinfo:
-            f({"host": 12345})
-        assert str(excinfo.value) == "Unknown server provided: {'host': 12345}"
+        with pytest.raises(ValueError, match="Unsupported server specification"):
+            f(None)  # type: ignore
 
-        with pytest.raises(ValueError) as excinfo:
-            f(12345)
-        assert str(excinfo.value) == "Unknown server provided: 12345"
+        with pytest.raises(ValueError, match="Unsupported server specification"):
+            f({"host": 12345})  # type: ignore
+
+        with pytest.raises(ValueError, match="Unsupported server specification"):
+            f(12345)  # type: ignore
 
 
 @pytest.mark.unit()
diff --git a/pymemcache/test/test_client_retry.py b/pymemcache/test/test_client_retry.py
index bcf5396..293270f 100644
--- a/pymemcache/test/test_client_retry.py
+++ b/pymemcache/test/test_client_retry.py
@@ -15,7 +15,7 @@ from pymemcache.exceptions import MemcacheUnknownError, MemcacheClientError
 # Test pure passthroughs with no retry action.
 class TestRetryingClientPassthrough(ClientTestMixin, unittest.TestCase):
     def make_base_client(self, mock_socket_values, **kwargs):
-        base_client = Client(None, **kwargs)
+        base_client = Client("localhost", **kwargs)
         # mock out client._connect() rather than hard-setting client.sock to
         # ensure methods are checking whether self.sock is None before
         # attempting to use it
@@ -41,7 +41,7 @@ class TestRetryingClientPassthrough(ClientTestMixin, unittest.TestCase):
 class TestRetryingClient(object):
     def make_base_client(self, mock_socket_values, **kwargs):
         """Creates a regular mock client to wrap in the RetryClient."""
-        base_client = Client(None, **kwargs)
+        base_client = Client("localhost", **kwargs)
         # mock out client._connect() rather than hard-setting client.sock to
         # ensure methods are checking whether self.sock is None before
         # attempting to use it