fix: handle dangling symlink when linking node binary (#10972)

existsSync() follows symlinks and returns false for broken symlinks,
so a dangling symlink from a previous node install would not be removed
before creating the new symlink, causing an EEXIST error.

Use rimraf unconditionally instead, which handles both existing files
and non-existent paths gracefully.

.changeset/fix-link-bin-dangling-symlink.md

@@ -0,0 +1,6 @@
+---
+"@pnpm/link-bins": patch
+"pnpm": patch
+---
+
+Fixed `EEXIST` error when globally installing `node` while a dangling symlink exists from a previous installation.

pkg-manager/link-bins/src/index.ts

@@ -310,13 +310,10 @@ async function linkBin (cmd: CommandInfo, binsDir: string, opts?: LinkBinOptions
   } else if (cmd.name === 'node') {
     // On non-Windows, node should be symlinked directly to the binary
     // instead of wrapped in a shell shim.
-    try {
-      if (existsSync(externalBinPath)) {
-        await rimraf(externalBinPath)
-      }
-    } catch (err: unknown) {
-      if ((err as NodeJS.ErrnoException).code !== 'ENOENT') throw err
-    }
+    // Use rimraf unconditionally instead of existsSync check, because
+    // existsSync follows symlinks and returns false for broken symlinks,
+    // causing EEXIST when the dangling symlink still exists on disk.
+    await rimraf(externalBinPath)
     await fs.symlink(cmd.path, externalBinPath, 'file')
     return
   }

pkg-manager/link-bins/test/index.ts

@@ -630,6 +630,43 @@ describe('node binary linking', () => {
       expect(stat.isSymbolicLink()).toBe(true)
       expect(fs.realpathSync(binLocation)).toBe(path.join(nodeBinDir, 'node'))
     })
+
+    test('linkBinsOfPackages() replaces a dangling symlink when linking node binary', async () => {
+      const binTarget = temporaryDirectory()
+      const nodeDir = temporaryDirectory()
+
+      const nodeBinDir = path.join(nodeDir, 'bin')
+      fs.mkdirSync(nodeBinDir, { recursive: true })
+      fs.writeFileSync(path.join(nodeBinDir, 'node'), 'fake-node-binary', 'utf8')
+
+      // Create a dangling symlink at the target path (simulates a previous
+      // node install whose store entry was removed).
+      const binLocation = path.join(binTarget, 'node')
+      fs.mkdirSync(binTarget, { recursive: true })
+      const danglingTarget = path.join(temporaryDirectory(), 'non-existent-target')
+      fs.symlinkSync(danglingTarget, binLocation)
+      // Verify it's dangling: lstat succeeds but existsSync returns false
+      expect(fs.lstatSync(binLocation).isSymbolicLink()).toBe(true)
+      expect(fs.existsSync(binLocation)).toBe(false)
+
+      await linkBinsOfPackages(
+        [
+          {
+            location: nodeDir,
+            manifest: {
+              name: 'node',
+              version: '20.0.0',
+              bin: { node: 'bin/node' },
+            },
+          },
+        ],
+        binTarget
+      )
+
+      const stat = fs.lstatSync(binLocation)
+      expect(stat.isSymbolicLink()).toBe(true)
+      expect(fs.realpathSync(binLocation)).toBe(path.join(nodeBinDir, 'node'))
+    })
   }
 
   testOnWindows('linkBinsOfPackages() hardlinks node.exe instead of creating a cmd-shim', async () => {