Only set token if bind is True

Author: aclark4life

pymongo/asynchronous/client_session.py

@@ -548,7 +548,8 @@ def _check_ended(self) -> None:
             raise InvalidOperation("Cannot use ended session")
 
     async def __aenter__(self) -> AsyncClientSession:
-        self._token = _SESSION.set(self)
+        if self._options._bind:
+            self._token = _SESSION.set(self)
         return self
 
     async def __aexit__(self, exc_type: Any, exc_val: Any, exc_tb: Any) -> None:

pymongo/synchronous/client_session.py

@@ -547,7 +547,8 @@ def _check_ended(self) -> None:
             raise InvalidOperation("Cannot use ended session")
 
     def __enter__(self) -> ClientSession:
-        self._token = _SESSION.set(self)
+        if self._options._bind:
+            self._token = _SESSION.set(self)
         return self
 
     def __exit__(self, exc_type: Any, exc_val: Any, exc_tb: Any) -> None: