From 21d2553c35d0ef2db3f7a3afaabf5d6b0f2aef94 Mon Sep 17 00:00:00 2001
From: Donna Belsey <5080993+donnabelsey@users.noreply.github.com>
Date: Wed, 15 Oct 2025 15:38:54 +0100
Subject: [PATCH 1/2] fix: Handle location header array with a single value
 without emitting warning

Co-authored with @brunns
Related to #977
---
 packages/open-next/src/http/util.ts          |  2 +-
 packages/tests-unit/tests/http/utils.test.ts | 16 ++++++++++++++++
 2 files changed, 17 insertions(+), 1 deletion(-)

diff --git a/packages/open-next/src/http/util.ts b/packages/open-next/src/http/util.ts
index de3b07de6..19f479b97 100644
--- a/packages/open-next/src/http/util.ts
+++ b/packages/open-next/src/http/util.ts
@@ -23,7 +23,7 @@ export const parseHeaders = (
      * and https://github.com/opennextjs/opennextjs-aws/pull/977#issuecomment-3261763114
      */
     if (keyLower === "location" && Array.isArray(value)) {
-      if (value[0] === value[1]) {
+      if (value.length === 1 || value[0] === value[1]) {
         result[keyLower] = value[0];
       } else {
         logger.warn(
diff --git a/packages/tests-unit/tests/http/utils.test.ts b/packages/tests-unit/tests/http/utils.test.ts
index 34f0717dc..79670c555 100644
--- a/packages/tests-unit/tests/http/utils.test.ts
+++ b/packages/tests-unit/tests/http/utils.test.ts
@@ -65,4 +65,20 @@ describe("parseHeaders", () => {
       "x-opennext": "is-so-cool",
     });
   });
+
+  it("handles location header array with a single value", () => {
+    const headers = parseHeaders({
+      location: ["/target"],
+      "x-custom-header": "customValue",
+      "x-multiple-values": ["value1", "value2"],
+      "x-undefined-header": undefined,
+      "x-opennext": "is-so-cool",
+    } as unknown as http.OutgoingHttpHeaders);
+    expect(headers).toEqual({
+      location: "/target",
+      "x-custom-header": "customValue",
+      "x-multiple-values": "value1,value2",
+      "x-opennext": "is-so-cool",
+    });
+  });
 });

From c8959c0f9e6e02d7f2707b510ecee67f3068400a Mon Sep 17 00:00:00 2001
From: Donna Belsey <5080993+donnabelsey@users.noreply.github.com>
Date: Wed, 15 Oct 2025 16:00:52 +0100
Subject: [PATCH 2/2] Add changeset

Co-authored with @brunns
---
 .changeset/slimy-squids-juggle.md | 5 +++++
 1 file changed, 5 insertions(+)
 create mode 100644 .changeset/slimy-squids-juggle.md

diff --git a/.changeset/slimy-squids-juggle.md b/.changeset/slimy-squids-juggle.md
new file mode 100644
index 000000000..b610db5cb
--- /dev/null
+++ b/.changeset/slimy-squids-juggle.md
@@ -0,0 +1,5 @@
+---
+"@opennextjs/aws": patch
+---
+
+fix: Handle location header array with a single value without emitting warning