fix: fix PowerShell completion argument parsing

.changeset/curvy-clouds-hide.md

@@ -0,0 +1,5 @@
+---
+'@bomb.sh/tab': patch
+---
+
+Fix PowerShell completion argument parsing

bin/cli.ts

@@ -9,6 +9,11 @@ const shells = ['zsh', 'bash', 'fish', 'powershell'];
 
 async function main() {
   const args = process.argv.slice(2);
+  const isPowerShell = process.platform === 'win32' && process.env.PSModulePath;
+
+  if (process.env.TAB_DEBUG) {
+    console.error('RAW ARGS:', process.argv);
+  }
 
   // <packageManager> complete -- <args>
   if (args.length >= 2 && args[1] === 'complete') {
@@ -23,16 +28,27 @@ async function main() {
     }
 
     const dashIndex = process.argv.indexOf('--');
-    if (dashIndex !== -1) {
-      const completion = new PackageManagerCompletion(packageManager);
-      await setupCompletionForPackageManager(packageManager, completion);
-      const toComplete = process.argv.slice(dashIndex + 1);
-      await completion.parse(toComplete);
-      process.exit(0);
-    } else {
+    // PowerShell's argument parsing can normalize or drop a `--`
+    // our "<pm> complete -- <query>" POSIX-style contract doesn't work the same way.
+    // so we need to handle the PowerShell case separately.
+    // gh issue discussion: https://github.com/bombshell-dev/tab/issues/82
+
+    const completionArgs =
+      dashIndex !== -1 && (!isPowerShell || dashIndex < process.argv.length - 1)
+        ? process.argv.slice(dashIndex + 1)
+        : isPowerShell
+          ? args.slice(2)
+          : null;
+
+    if (!completionArgs) {
       console.error(`Error: Expected '--' followed by command to complete`);
       process.exit(1);
     }
+
+    const completion = new PackageManagerCompletion(packageManager);
+    await setupCompletionForPackageManager(packageManager, completion);
+    await completion.parse(completionArgs);
+    process.exit(0);
   }
 
   // <packageManager> <shell>