From 7df00bc3db392afa5211c60fb16c1237741c2bb3 Mon Sep 17 00:00:00 2001
From: Zoltan Kochan <z@kochan.io>
Date: Tue, 24 Mar 2026 15:57:06 +0100
Subject: [PATCH] fix: use ENOENT check instead of which.sync for
 command-not-found on Windows (#11004)

Cherry-picked from main (e9318ce974).
---
 .../fix-windows-exec-command-not-found.md     |  6 +++++
 .../src/exec.ts                               | 23 ++++++++++---------
 2 files changed, 18 insertions(+), 11 deletions(-)
 create mode 100644 .changeset/fix-windows-exec-command-not-found.md

diff --git a/.changeset/fix-windows-exec-command-not-found.md b/.changeset/fix-windows-exec-command-not-found.md
new file mode 100644
index 0000000000..f9e818f500
--- /dev/null
+++ b/.changeset/fix-windows-exec-command-not-found.md
@@ -0,0 +1,6 @@
+---
+"@pnpm/plugin-commands-script-runners": patch
+"pnpm": patch
+---
+
+Fixed false "Command not found" errors on Windows when a command exists in PATH but exits with a non-zero code. Also fixed path resolution for `--filter` contexts where the command runs in a different package directory.
diff --git a/exec/plugin-commands-script-runners/src/exec.ts b/exec/plugin-commands-script-runners/src/exec.ts
index 3f66fc5283..694d8965c0 100644
--- a/exec/plugin-commands-script-runners/src/exec.ts
+++ b/exec/plugin-commands-script-runners/src/exec.ts
@@ -304,7 +304,7 @@ export async function handler (
           result[prefix].status = 'passed'
           result[prefix].duration = getExecutionDuration(startTime)
         } catch (err: any) { // eslint-disable-line
-          if (isErrorCommandNotFound(params[0], err, prependPaths)) {
+          if (isErrorCommandNotFound(params[0], err, prefix, prependPaths)) {
             err.message = `Command "${params[0]}" not found`
             err.hint = await createExecCommandNotFoundHint(params[0], {
               implicitlyFellbackFromRun: opts.implicitlyFellbackFromRun ?? false,
@@ -398,19 +398,20 @@ interface CommandError extends Error {
   shortMessage: string
 }
 
-function isErrorCommandNotFound (command: string, error: CommandError, prependPaths: string[]): boolean {
-  // Mac/Linux
-  if (process.platform === 'linux' || process.platform === 'darwin') {
-    return error.originalMessage === `spawn ${command} ENOENT`
+function isErrorCommandNotFound (command: string, error: CommandError, prefix: string, prependPaths: string[]): boolean {
+  if (error.originalMessage === `spawn ${command} ENOENT`) {
+    return true
   }
 
-  // Windows
+  // On Windows, execa 9.x uses cross-spawn only for command parsing (not spawning),
+  // so cross-spawn's ENOENT hook never fires. Non-existent commands get wrapped as
+  // `cmd.exe /c <command>` which exits with code 1 instead of emitting ENOENT.
+  // Fall back to checking if the command exists in PATH, resolving relative paths
+  // against the exec prefix to correctly handle --filter contexts.
   if (process.platform === 'win32') {
-    const { value: path } = prependDirsToPath(prependPaths)
-    return !which.sync(command, {
-      nothrow: true,
-      path,
-    })
+    const absolutePrependPaths = prependPaths.map(p => path.resolve(prefix, p))
+    const { value: searchPath } = prependDirsToPath(absolutePrependPaths)
+    return !which.sync(command, { nothrow: true, path: searchPath })
   }
 
   return false