From 3e4ac54fc3ac95a3c566fff5b2d80ea8c046a26a Mon Sep 17 00:00:00 2001
From: Hai <haijie0619@gmail.com>
Date: Tue, 22 Sep 2026 15:56:54 +0800
Subject: [PATCH] perf: skip source map composition for a single minimizer

---
 src/minify.js | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/src/minify.js b/src/minify.js
index 425c0299..1d792cc7 100644
--- a/src/minify.js
+++ b/src/minify.js
@@ -545,7 +545,9 @@ async function minify(options) {
       // the final map points back to the original sources. Bytes carry none.
       lastMap = Buffer.isBuffer(result.code)
         ? undefined
-        : composeSourceMaps(result.map, currentMap, name);
+        : implementations.length === 1
+          ? result.map
+          : composeSourceMaps(result.map, currentMap, name);
     }
   }