Stop using twisted.internet.defer.returnValue (#18020)

`defer.returnValue` was only needed in Python 2; in Python 3, a simple
`return` is fine.

`twisted.internet.defer.returnValue` is deprecated as of Twisted 24.7.0.

Most uses of `returnValue` in synapse were removed a while back; this
cleans up some remaining bits.

1 files changed, 1 insertions, 18 deletions

diff --git a/synapse/logging/scopecontextmanager.py b/synapse/logging/scopecontextmanager.py

index 581e6d6411..feaadc4d87 100644
--- a/synapse/logging/scopecontextmanager.py
+++ b/synapse/logging/scopecontextmanager.py
@@ -20,13 +20,10 @@
 #
 
 import logging
-from types import TracebackType
-from typing import Optional, Type
+from typing import Optional
 
 from opentracing import Scope, ScopeManager, Span
 
-import twisted
-
 from synapse.logging.context import (
     LoggingContext,
     current_context,
@@ -112,9 +109,6 @@ class _LogContextScope(Scope):
     """
     A custom opentracing scope, associated with a LogContext
 
-      * filters out _DefGen_Return exceptions which arise from calling
-        `defer.returnValue` in Twisted code
-
       * When the scope is closed, the logcontext's active scope is reset to None.
         and - if enter_logcontext was set - the logcontext is finished too.
     """
@@ -146,17 +140,6 @@ class _LogContextScope(Scope):
         self._finish_on_close = finish_on_close
         self._enter_logcontext = enter_logcontext
 
-    def __exit__(
-        self,
-        exc_type: Optional[Type[BaseException]],
-        value: Optional[BaseException],
-        traceback: Optional[TracebackType],
-    ) -> None:
-        if exc_type == twisted.internet.defer._DefGen_Return:
-            # filter out defer.returnValue() calls
-            exc_type = value = traceback = None
-        super().__exit__(exc_type, value, traceback)
-
     def __str__(self) -> str:
         return f"Scope<{self.span}>"