From 4261e9ff6f73bf055836e3805ca07af12485ce8b Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 9 Feb 2024 17:33:27 -0500
Subject: [PATCH] fix(plugins): avoid converting array to object when tracking
 atomics within a transaction

Re: #14340
---
 lib/plugins/trackTransaction.js | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/lib/plugins/trackTransaction.js b/lib/plugins/trackTransaction.js
index 1a409a026eb..5920555324c 100644
--- a/lib/plugins/trackTransaction.js
+++ b/lib/plugins/trackTransaction.js
@@ -85,7 +85,12 @@ function mergeAtomics(destination, source) {
     destination.$addToSet = (destination.$addToSet || []).concat(source.$addToSet);
   }
   if (source.$set != null) {
-    destination.$set = Object.assign(destination.$set || {}, source.$set);
+    if (Array.isArray(destination.$set || []) && Array.isArray(source.$set || [])) {
+      destination.$set = (destination.$set || []).concat(source.$set);
+    } else {
+      destination.$set = Object.assign(destination.$set || {}, source.$set);
+    }
+
   }
 
   return destination;