[10.x] Mark commands as isolatable (laravel#46925)

* Ability to set default for --isolated option

* set default exit code

* Update Command.php

---------

Co-authored-by: Taylor Otwell <taylor@laravel.com>

src/Illuminate/Console/Command.php

@@ -61,6 +61,20 @@ class Command extends SymfonyCommand
      */
     protected $hidden = false;
 
+    /**
+     * Indicates whether only one instance of the command can run at any given time.
+     *
+     * @var bool
+     */
+    protected $isolated = false;
+
+    /**
+     * The default exit code for isolated commands.
+     *
+     * @var int
+     */
+    protected $isolatedExitCode = self::SUCCESS;
+
     /**
      * The console command name aliases.
      *
@@ -140,7 +154,7 @@ protected function configureIsolation()
             null,
             InputOption::VALUE_OPTIONAL,
             'Do not run the command if another instance of the command is already running',
-            false
+            $this->isolated
         ));
     }
 
@@ -185,7 +199,7 @@ protected function execute(InputInterface $input, OutputInterface $output)
 
             return (int) (is_numeric($this->option('isolated'))
                         ? $this->option('isolated')
-                        : self::SUCCESS);
+                        : $this->isolatedExitCode);
         }
 
         $method = method_exists($this, 'handle') ? 'handle' : '__invoke';