Use mypy 1.0

changelog.d/15052.misc

@@ -0,0 +1 @@
+Improve type hints.

synapse/__init__.py

@@ -64,7 +64,9 @@
 try:
     from canonicaljson import set_json_library
 
-    set_json_library(json)
+    # type-ignore: I think there has been a regression in mypy 1.0.0 in how it checks
+    # modules against Protocols.
+    set_json_library(json)  # type: ignore[arg-type]
 except ImportError:
     pass
 

synapse/handlers/ui_auth/checkers.py

@@ -39,6 +39,7 @@ def is_enabled(self) -> bool:
         Returns:
             True if this login type is enabled.
         """
+        raise NotImplementedError()
 
     async def check_auth(self, authdict: dict, clientip: str) -> Any:
         """Given the authentication dict from the client, attempt to check this step

synapse/http/matrixfederationclient.py

@@ -1267,7 +1267,7 @@ async def get_file(
 def _flatten_response_never_received(e: BaseException) -> str:
     if hasattr(e, "reasons"):
         reasons = ", ".join(
-            _flatten_response_never_received(f.value) for f in e.reasons  # type: ignore[attr-defined]
+            _flatten_response_never_received(f.value) for f in e.reasons
         )
 
         return "%s:[%s]" % (type(e).__name__, reasons)

synapse/logging/opentracing.py

@@ -188,7 +188,7 @@ def set_fates(clotho, lachesis, atropos, father="Zues", mother="Themis"):
 )
 
 import attr
-from typing_extensions import ParamSpec
+from typing_extensions import Concatenate, ParamSpec
 
 from twisted.internet import defer
 from twisted.web.http import Request
@@ -445,7 +445,7 @@ def init_tracer(hs: "HomeServer") -> None:
         opentracing = None  # type: ignore[assignment]
         return
 
-    if not opentracing or not JaegerConfig:
+    if opentracing is None or JaegerConfig is None:
         raise ConfigError(
             "The server has been configured to use opentracing but opentracing is not "
             "installed."
@@ -864,7 +864,7 @@ def extract_text_map(carrier: Dict[str, str]) -> Optional["opentracing.SpanConte
 
 def _custom_sync_async_decorator(
     func: Callable[P, R],
-    wrapping_logic: Callable[[Callable[P, R], Any, Any], ContextManager[None]],
+    wrapping_logic: Callable[Concatenate[Callable[P, R], P], ContextManager[None]],
 ) -> Callable[P, R]:
     """
     Decorates a function that is sync or async (coroutines), or that returns a Twisted
@@ -964,7 +964,10 @@ def _decorator(func: Callable[P, R]) -> Callable[P, R]:
         if not opentracing:
             return func
 
-        return _custom_sync_async_decorator(func, _wrapping_logic)
+        # type-ignore: mypy seems to be confused by the ParamSpecs here.
+        return _custom_sync_async_decorator(
+            func, _wrapping_logic  # type: ignore[arg-type]
+        )
 
     return _decorator
 
@@ -1010,7 +1013,8 @@ def _wrapping_logic(
         set_tag(SynapseTags.FUNC_KWARGS, str(kwargs))
         yield
 
-    return _custom_sync_async_decorator(func, _wrapping_logic)
+    # type-ignore: mypy seems to be confused by the ParamSpecs here.
+    return _custom_sync_async_decorator(func, _wrapping_logic)  # type: ignore[arg-type]
 
 
 @contextlib.contextmanager

synapse/rest/media/v1/_base.py

@@ -300,6 +300,7 @@ def write_to_consumer(self, consumer: IConsumer) -> Awaitable:
         Returns:
             Resolves once the response has finished being written
         """
+        raise NotImplementedError()
 
     def __enter__(self) -> None:
         pass

synapse/storage/engines/__init__.py

@@ -25,7 +25,7 @@
 except ImportError:
 
     class PostgresEngine(BaseDatabaseEngine):  # type: ignore[no-redef]
-        def __new__(cls, *args: object, **kwargs: object) -> NoReturn:  # type: ignore[misc]
+        def __new__(cls, *args: object, **kwargs: object) -> NoReturn:
             raise RuntimeError(
                 f"Cannot create {cls.__name__} -- psycopg2 module is not installed"
             )
@@ -36,7 +36,7 @@ def __new__(cls, *args: object, **kwargs: object) -> NoReturn:  # type: ignore[m
 except ImportError:
 
     class Sqlite3Engine(BaseDatabaseEngine):  # type: ignore[no-redef]
-        def __new__(cls, *args: object, **kwargs: object) -> NoReturn:  # type: ignore[misc]
+        def __new__(cls, *args: object, **kwargs: object) -> NoReturn:
             raise RuntimeError(
                 f"Cannot create {cls.__name__} -- sqlite3 module is not installed"
             )

synapse/storage/engines/postgres.py

@@ -22,7 +22,7 @@
     IncorrectDatabaseSetup,
     IsolationLevel,
 )
-from synapse.storage.types import Cursor
+from synapse.storage.types import Cursor, DBAPI2Module
 
 if TYPE_CHECKING:
     from synapse.storage.database import LoggingDatabaseConnection
@@ -35,7 +35,9 @@ class PostgresEngine(
     BaseDatabaseEngine[psycopg2.extensions.connection, psycopg2.extensions.cursor]
 ):
     def __init__(self, database_config: Mapping[str, Any]):
-        super().__init__(psycopg2, database_config)
+        # Cast: mypy 1.0.0 doesn't seem to think that the module implements the protocol.
+        # AFAICS this is a false positive.
+        super().__init__(cast(DBAPI2Module, psycopg2), database_config)
         psycopg2.extensions.register_type(psycopg2.extensions.UNICODE)
 
         # Disables passing `bytes` to txn.execute, c.f. #6186. If you do

synapse/storage/engines/sqlite.py

@@ -15,18 +15,20 @@
 import sqlite3
 import struct
 import threading
-from typing import TYPE_CHECKING, Any, List, Mapping, Optional
+from typing import TYPE_CHECKING, Any, List, Mapping, Optional, cast
 
 from synapse.storage.engines import BaseDatabaseEngine
-from synapse.storage.types import Cursor
+from synapse.storage.types import Cursor, DBAPI2Module
 
 if TYPE_CHECKING:
     from synapse.storage.database import LoggingDatabaseConnection
 
 
 class Sqlite3Engine(BaseDatabaseEngine[sqlite3.Connection, sqlite3.Cursor]):
     def __init__(self, database_config: Mapping[str, Any]):
-        super().__init__(sqlite3, database_config)
+        # Cast: mypy 1.0.0 doesn't seem to think that the module implements the protocol.
+        # AFAICS this is a false positive.
+        super().__init__(cast(DBAPI2Module, sqlite3), database_config)
 
         database = database_config.get("args", {}).get("database")
         self._is_in_memory = database in (

synapse/streams/__init__.py

@@ -32,4 +32,4 @@ async def get_new_events(
         is_guest: bool,
         explicit_room_id: Optional[str] = None,
     ) -> Tuple[List[R], K]:
-        ...
+        raise NotImplementedError()

tests/handlers/test_register.py

@@ -62,7 +62,7 @@ async def check_registration_for_spam(
         request_info: Collection[Tuple[str, str]],
         auth_provider_id: Optional[str],
     ) -> RegistrationBehaviour:
-        pass
+        return RegistrationBehaviour.ALLOW
 
 
 class DenyAll(TestSpamChecker):
@@ -111,7 +111,7 @@ async def check_registration_for_spam(
         username: Optional[str],
         request_info: Collection[Tuple[str, str]],
     ) -> RegistrationBehaviour:
-        pass
+        return RegistrationBehaviour.ALLOW
 
 
 class LegacyAllowAll(TestLegacyRegistrationSpamChecker):

tests/http/federation/test_matrix_federation_agent.py

@@ -63,7 +63,7 @@
     get_test_ca_cert_file,
 )
 from tests.server import FakeTransport, ThreadedMemoryReactorClock
-from tests.utils import default_config
+from tests.utils import checked_cast, default_config
 
 logger = logging.getLogger(__name__)
 
@@ -146,8 +146,10 @@ def _make_connection(
         #
         # Normally this would be done by the TCP socket code in Twisted, but we are
         # stubbing that out here.
-        client_protocol = client_factory.buildProtocol(dummy_address)
-        assert isinstance(client_protocol, _WrappingProtocol)
+        # NB: we use a checked_cast here to workaround https://github.com/Shoobx/mypy-zope/issues/91)
+        client_protocol = checked_cast(
+            _WrappingProtocol, client_factory.buildProtocol(dummy_address)
+        )
         client_protocol.makeConnection(
             FakeTransport(server_protocol, self.reactor, client_protocol)
         )
@@ -446,7 +448,6 @@ def _do_get_via_proxy(
         server_ssl_protocol = _wrap_server_factory_for_tls(
             _get_test_protocol_factory()
         ).buildProtocol(dummy_address)
-        assert isinstance(server_ssl_protocol, TLSMemoryBIOProtocol)
 
         # Tell the HTTP server to send outgoing traffic back via the proxy's transport.
         proxy_server_transport = proxy_server.transport
@@ -1529,7 +1530,7 @@ def _check_logcontext(context: LoggingContextOrSentinel) -> None:
 
 def _wrap_server_factory_for_tls(
     factory: IProtocolFactory, sanlist: Optional[List[bytes]] = None
-) -> IProtocolFactory:
+) -> TLSMemoryBIOFactory:
     """Wrap an existing Protocol Factory with a test TLSMemoryBIOFactory
     The resultant factory will create a TLS server which presents a certificate
     signed by our test CA, valid for the domains in `sanlist`