use function

Author: baileympearson

src/mongo_client.ts

@@ -799,13 +799,28 @@ export class MongoClient extends TypedEventEmitter<MongoClientEvents> implements
     const areSessionsSupported = topologyDescription.logicalSessionTimeoutMinutes != null;
 
     if (areSessionsSupported) {
+      await endSessions(this);
+    }
+
+    // clear out references to old topology
+    const topology = this.topology;
+    this.topology = undefined;
+
+    topology.close();
+
+    const { encrypter } = this.options;
+    if (encrypter) {
+      await encrypter.close(this);
+    }
+
+    async function endSessions(client: MongoClient) {
       // If we would attempt to select a server and get nothing back we short circuit
       // to avoid the server selection timeout.
       const selector = readPreferenceServerSelector(ReadPreference.primaryPreferred);
       const serverDescriptions = Array.from(topologyDescription.servers.values());
       const servers = selector(topologyDescription, serverDescriptions);
       if (servers.length !== 0) {
-        const endSessions = Array.from(this.s.sessionPool.sessions, ({ id }) => id);
+        const endSessions = Array.from(client.s.sessionPool.sessions, ({ id }) => id);
         if (endSessions.length !== 0) {
           try {
             class EndSessionsOperation extends AbstractOperation<void> {
@@ -827,24 +842,13 @@ export class MongoClient extends TypedEventEmitter<MongoClientEvents> implements
                 return 'endSessions';
               }
             }
-            await executeOperation(this, new EndSessionsOperation());
+            await executeOperation(client, new EndSessionsOperation());
           } catch (error) {
             squashError(error);
           }
         }
       }
     }
-
-    // clear out references to old topology
-    const topology = this.topology;
-    this.topology = undefined;
-
-    topology.close();
-
-    const { encrypter } = this.options;
-    if (encrypter) {
-      await encrypter.close(this);
-    }
   }
 
   /**