From 2714c83de89e5c2dccf9f98937e14f2bcafee5fc Mon Sep 17 00:00:00 2001
From: w287346141 <57440615+w287346141@users.noreply.github.com>
Date: Mon, 1 Jun 2026 11:46:08 +0800
Subject: [PATCH] Fix npm update prefix for symlinked bins

---
 src/version.ts        |  8 +++++++-
 tests/version.test.ts | 27 +++++++++++++++++++++++++++
 2 files changed, 34 insertions(+), 1 deletion(-)

diff --git a/src/version.ts b/src/version.ts
index 0816ac2..11d5b8b 100644
--- a/src/version.ts
+++ b/src/version.ts
@@ -172,7 +172,13 @@ export function isNpxInstall(): boolean {
 export function detectNpmInstallPrefix(bin?: string): string | null {
   const raw = bin ?? process.argv[1] ?? "";
   if (!raw) return null;
-  const norm = raw.replace(/\\/g, "/");
+  let resolved = raw;
+  try {
+    resolved = realpathSync(raw);
+  } catch {
+    /* synthetic / nonexistent path (e.g. in tests) -- keep the literal argv */
+  }
+  const norm = resolved.replace(/\\/g, "/");
   const posix = norm.match(/^(.+?)\/lib\/node_modules\/@carboncode\/cli(?:\/|$)/i);
   if (posix) return posix[1] ?? null;
   const win = norm.match(/^(.+?)\/node_modules\/@carboncode\/cli(?:\/|$)/i);
diff --git a/tests/version.test.ts b/tests/version.test.ts
index e160cf7..06c3444 100644
--- a/tests/version.test.ts
+++ b/tests/version.test.ts
@@ -209,6 +209,33 @@ describe("detectNpmInstallPrefix", () => {
     ).toBe("C:/Users/me/AppData/Roaming/npm");
   });
 
+  it("resolves a bin symlink before extracting the npm prefix", () => {
+    const dir = mkdtempSync(join(tmpdir(), "cc-prefix-"));
+    try {
+      const target = join(
+        dir,
+        "lib",
+        "node_modules",
+        "@carboncode",
+        "cli",
+        "dist",
+        "cli",
+        "index.js",
+      );
+      mkdirSync(join(dir, "lib", "node_modules", "@carboncode", "cli", "dist", "cli"), {
+        recursive: true,
+      });
+      writeFileSync(target, "#!/usr/bin/env node\n");
+      mkdirSync(join(dir, "bin"));
+      const link = join(dir, "bin", "carboncode");
+      symlinkSync(target, link);
+
+      expect(detectNpmInstallPrefix(link)).toBe(dir.replace(/\\/g, "/"));
+    } finally {
+      rmSync(dir, { recursive: true, force: true });
+    }
+  });
+
   it("returns null when no @carboncode/cli node_modules segment is present", () => {
     expect(detectNpmInstallPrefix("/opt/custom/bin/carboncode")).toBeNull();
   });