Command: fail() should show a readable message

fixes #2567

doc/82-Changelog.md

@@ -28,6 +28,7 @@ v1.10.0 (unreleased)
 * FIX: config deploy doesn't try to wait in case of no deployment (#2522)
 * FEATURE: improved wording for deployment error messages (#2523)
 * FEATURE: JSON can now be shipped via STDIN (#1570)
+* FEATURE: improved readability for some error messages (#2567)
 
 1.9.1
 -----

library/Director/Cli/Command.php

@@ -38,6 +38,10 @@ class Command extends CliCommand
         }
     }
 
+    /**
+     * @param string $msg
+     * @return never-return
+     */
     public function fail($msg)
     {
         $args = func_get_args();
@@ -45,8 +49,8 @@ class Command extends CliCommand
         if (count($args)) {
             $msg = vsprintf($msg, $args);
         }
-
-        throw new RuntimeException($msg);
+        echo $this->screen->colorize("ERROR", 'red') . ": $msg\n";
+        exit(1);
     }
 
     /**