From fd5ad38f3819d032e980f5297b36b4f5937d3929 Mon Sep 17 00:00:00 2001
From: Leon Sorokin <leeoniya@gmail.com>
Date: Wed, 25 Oct 2023 19:05:03 -0500
Subject: [PATCH] Transformers: Avoid mutating field.values in Concatenate
 transformation (#77179)

---
 .../grafana-data/src/transformations/transformers/concat.ts     | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/packages/grafana-data/src/transformations/transformers/concat.ts b/packages/grafana-data/src/transformations/transformers/concat.ts
index a8cb3794e20..af7eed772d4 100644
--- a/packages/grafana-data/src/transformations/transformers/concat.ts
+++ b/packages/grafana-data/src/transformations/transformers/concat.ts
@@ -89,7 +89,7 @@ export function concatenateFields(data: DataFrame[], opts: ConcatenateTransforme
       if (f.values.length === maxLength) {
         return f;
       }
-      const values = f.values;
+      const values = f.values.slice();
       values.length = maxLength;
       return {
         ...f,