Upgrade mypy to version 0.931 (#12030)

Upgrade mypy to 0.931, mypy-zope to 0.3.5 and fix new complaints.

synapse/util/daemonize.py

@@ -20,7 +20,7 @@ import os
 import signal
 import sys
 from types import FrameType, TracebackType
-from typing import NoReturn, Type
+from typing import NoReturn, Optional, Type
 
 
 def daemonize_process(pid_file: str, logger: logging.Logger, chdir: str = "/") -> None:
@@ -100,7 +100,9 @@ def daemonize_process(pid_file: str, logger: logging.Logger, chdir: str = "/") -
     # also catch any other uncaught exceptions before we get that far.)
 
     def excepthook(
-        type_: Type[BaseException], value: BaseException, traceback: TracebackType
+        type_: Type[BaseException],
+        value: BaseException,
+        traceback: Optional[TracebackType],
     ) -> None:
         logger.critical("Unhanded exception", exc_info=(type_, value, traceback))
 
@@ -123,7 +125,7 @@ def daemonize_process(pid_file: str, logger: logging.Logger, chdir: str = "/") -
         sys.exit(1)
 
     # write a log line on SIGTERM.
-    def sigterm(signum: signal.Signals, frame: FrameType) -> NoReturn:
+    def sigterm(signum: int, frame: Optional[FrameType]) -> NoReturn:
         logger.warning("Caught signal %s. Stopping daemon." % signum)
         sys.exit(0)
 

synapse/util/patch_inline_callbacks.py

@@ -14,7 +14,7 @@
 
 import functools
 import sys
-from typing import Any, Callable, Generator, List, TypeVar
+from typing import Any, Callable, Generator, List, TypeVar, cast
 
 from twisted.internet import defer
 from twisted.internet.defer import Deferred
@@ -174,7 +174,9 @@ def _check_yield_points(
                         )
                     )
                     changes.append(err)
-                return getattr(e, "value", None)
+                # The `StopIteration` or `_DefGen_Return` contains the return value from the
+                # generator.
+                return cast(T, e.value)
 
             frame = gen.gi_frame