From 827ac3a61a5879987619a5d3143bec6132e91231 Mon Sep 17 00:00:00 2001
From: Ry Anderson <60347977+Omnicpie@users.noreply.github.com>
Date: Thu, 17 Jul 2025 11:04:26 +0100
Subject: [PATCH 1/2] fix(NODE-4763): tryNext not updating resumeToken for a
 given update

---
 src/change_stream.ts | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/change_stream.ts b/src/change_stream.ts
index ed847519e8a..ce90464e9d5 100644
--- a/src/change_stream.ts
+++ b/src/change_stream.ts
@@ -809,7 +809,8 @@ export class ChangeStream<
       while (true) {
         try {
           const change = await this.cursor.tryNext();
-          return change ?? null;
+          const processedChange = this._processChange(change ?? null);
+          return processedChange;
         } catch (error) {
           try {
             await this._processErrorIteratorMode(error, this.cursor.id != null);

From a9ab3c5cb73b62e45a3578a044bfe846661eed3b Mon Sep 17 00:00:00 2001
From: Ry Anderson <60347977+Omnicpie@users.noreply.github.com>
Date: Fri, 18 Jul 2025 13:45:15 +0100
Subject: [PATCH 2/2] fix(NODE-4763): Tweak logic to handle null changes
 without errors

---
 src/change_stream.ts | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/src/change_stream.ts b/src/change_stream.ts
index ce90464e9d5..a4718efc931 100644
--- a/src/change_stream.ts
+++ b/src/change_stream.ts
@@ -809,7 +809,13 @@ export class ChangeStream<
       while (true) {
         try {
           const change = await this.cursor.tryNext();
-          const processedChange = this._processChange(change ?? null);
+
+          // Prevent _processChange from producing an error due to a `null` change
+          if (!change) {
+            return null;
+          }
+
+          const processedChange = this._processChange(change);
           return processedChange;
         } catch (error) {
           try {