From 4e20cbb4d6f70d62b0bcfce3abffa47a9e55b94c Mon Sep 17 00:00:00 2001
From: Huang-404-Q <129407632+Huang-404-Q@users.noreply.github.com>
Date: Fri, 23 Oct 2026 20:03:17 +0800
Subject: [PATCH] fix(uploads): treat a missing message as an empty one (#7342)

The unsuccessful-upload branch called result.message.trim() directly. A
gateway or proxy that omits message turns a handled upload failure into a
TypeError while handling it, losing the clean "Upload failed" path.

Coerce a non-string message to an empty string before trimming.

The regression test sends success:false without a message and expects
"Upload failed"; it throws a TypeError on main.

Co-authored-by: Willem Jiang <willem.jiang@gmail.com>
---
 frontend/src/core/uploads/api.ts             |  5 ++++-
 frontend/tests/unit/core/uploads/api.test.ts | 12 ++++++++++++
 2 files changed, 16 insertions(+), 1 deletion(-)

diff --git a/frontend/src/core/uploads/api.ts b/frontend/src/core/uploads/api.ts
index 501cfe8c04..769f314979 100644
--- a/frontend/src/core/uploads/api.ts
+++ b/frontend/src/core/uploads/api.ts
@@ -147,7 +147,10 @@ export async function uploadFiles(
 
   const result = (await response.json()) as UploadResponse;
   if (result.success === false) {
-    const message = result.message.trim();
+    // A gateway or proxy may omit `message`; treat it like an empty one
+    // instead of throwing a TypeError while handling the failure.
+    const message =
+      typeof result.message === "string" ? result.message.trim() : "";
     throw new Error(
       message ? `Upload incomplete: ${message}` : "Upload failed",
     );
diff --git a/frontend/tests/unit/core/uploads/api.test.ts b/frontend/tests/unit/core/uploads/api.test.ts
index 105d307e7d..7b7fe19d6f 100644
--- a/frontend/tests/unit/core/uploads/api.test.ts
+++ b/frontend/tests/unit/core/uploads/api.test.ts
@@ -94,6 +94,18 @@ describe("uploads api", () => {
     expect(error.message).toBe("Upload failed");
   });
 
+  test("uses the upload fallback when an unsuccessful response omits the message", async () => {
+    const error = await uploadError(
+      jsonResponse(200, {
+        success: false,
+        files: [],
+        skipped_files: ["report.pdf"],
+      }),
+    );
+
+    expect(error.message).toBe("Upload failed");
+  });
+
   test("preserves string error details", async () => {
     const error = await uploadError(
       jsonResponse(413, { detail: "File exceeds the upload limit" }),