Added check for XDebug mode as an additional requirement to enable Fr…

…ankenPHP worker mode to avoid performance issues.

See the discussion with Kévin Dunglas in the PR discussion for the reasoning: #932

Essentially, disabling worker mode comes with performance drawbacks, but it's still the only sensible way to use FrankenPHP with XDebug.
By automatically turning off worker mode if
 a) the amount of workers isn't set explicitly,
 b) we're running locally, and
 c) XDebug is not installed, or it's mode is set to "off",
we get both optimal performance and XDebug working out of the box.

bin/checkXdebugMode.php

@@ -0,0 +1,3 @@
+<?php
+
+exit((ini_get('xdebug.mode') ?: 'off') === 'off' ? 0 : 1);

src/Commands/StartFrankenPhpCommand.php

@@ -10,6 +10,10 @@
 use Symfony\Component\Console\Command\SignalableCommandInterface;
 use Symfony\Component\Process\Process;
 
+use function app;
+use function base_path;
+use function dirname;
+
 #[AsCommand(name: 'octane:frankenphp')]
 class StartFrankenPhpCommand extends Command implements SignalableCommandInterface
 {
@@ -85,6 +89,9 @@ public function handle(ServerProcessInspector $inspector, ServerStateFile $serve
             ? "https://$host:$port"
             : "http://:$port";
 
+        $debugEnabled = $this->debugModeEnabled($frankenphpBinary);
+        $workerModeEnabled = $this->workerCount() == 0 && app()->environment('local') && ! $debugEnabled;
+
         $process = tap(new Process([
             $frankenphpBinary,
             'run',
@@ -93,14 +100,14 @@ public function handle(ServerProcessInspector $inspector, ServerStateFile $serve
             'APP_ENV' => app()->environment(),
             'APP_BASE_PATH' => base_path(),
             'APP_PUBLIC_PATH' => public_path(),
-            'APP_INDEX_FILE' => $this->workerCount() == 0 && app()->environment('local') ? 'index.php' : 'frankenphp-worker.php',
+            'APP_INDEX_FILE' => $workerModeEnabled ? 'frankenphp-worker.php' : 'index.php',
             'LARAVEL_OCTANE' => 1,
             'MAX_REQUESTS' => $this->option('max-requests'),
             'REQUEST_MAX_EXECUTION_TIME' => $this->maxExecutionTime(),
             'CADDY_GLOBAL_OPTIONS' => ($https && $this->option('http-redirect')) ? '' : 'auto_https disable_redirects',
             'CADDY_SERVER_ADMIN_PORT' => $this->adminPort(),
             'CADDY_SERVER_ADMIN_HOST' => $this->option('admin-host'),
-            'CADDY_SERVER_FRANKENPHP_OPTIONS' => $this->workerCount() == 0 && app()->environment('local') ? '' : 'import worker',
+            'CADDY_SERVER_FRANKENPHP_OPTIONS' => $workerModeEnabled ? 'import worker' : '',
             'CADDY_SERVER_LOG_LEVEL' => $this->option('log-level') ?: (app()->environment('local') ? 'INFO' : 'WARN'),
             'CADDY_SERVER_LOGGER' => 'json',
             'CADDY_SERVER_SERVER_NAME' => $serverName,
@@ -143,6 +150,24 @@ protected function ensurePortIsAvailable()
         }
     }
 
+    /**
+     * Check if XDebug is installed and enabled.
+     *
+     * @param string $frankenPhpBinary
+     *
+     * @return bool
+     */
+    protected function debugModeEnabled($frankenPhpBinary)
+    {
+        $status = tap(new Process([
+            $frankenPhpBinary,
+            'php-cli',
+            dirname(__DIR__, 2).'/bin/checkXdebugMode.php',
+        ], base_path()))->run();
+
+        return $status > 0;
+    }
+
     /**
      * Get the path to the FrankenPHP configuration file.
      *