From 19f01691d525f92642c184b9b4921857729a6034 Mon Sep 17 00:00:00 2001
From: Kausthubh J Rao <105716675+Exgene@users.noreply.github.com>
Date: Thu, 7 May 2026 07:33:08 +0530
Subject: [PATCH] fix(api): return 409 message instead of empty JSON for wrong
 commit id (#37572)

## Issue
Closes #37217

The error string was getting lost while returning due to `ctx.JSON()`
which cannot serialize the `error` object.

## Fix

Use `ctx.APIError()` to return proper error messages back to the client.
---
 routers/api/v1/repo/pull.go | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/routers/api/v1/repo/pull.go b/routers/api/v1/repo/pull.go
index 2426a6b3c2..2702f6864f 100644
--- a/routers/api/v1/repo/pull.go
+++ b/routers/api/v1/repo/pull.go
@@ -996,7 +996,7 @@ func MergePullRequest(ctx *context.APIContext) {
 				return
 			}
 			if strings.Contains(err.Error(), "Wrong commit ID") {
-				ctx.JSON(http.StatusConflict, err)
+				ctx.APIError(http.StatusConflict, err)
 				return
 			}
 			ctx.APIErrorInternal(err)