Merge "Fix --memory-limit option to maintenance scripts"

diff --combined maintenance/Maintenance.php
index 4d0af5f,e3b5f72..9685177
--- 1/maintenance/Maintenance.php
--- 2/maintenance/Maintenance.php
+++ b/maintenance/Maintenance.php
@@@ -25,7 -25,6 +25,7 @@@
  require_once __DIR__ . '/../includes/PHPVersionCheck.php';
  wfEntryPointCheck( 'cli' );
  
 +use MediaWiki\Shell\Shell;
  use Wikimedia\Rdbms\DBReplicationWaitError;
  
  /**
@@@ -509,7 -508,9 +509,9 @@@ abstract class Maintenance 
                $this->addOption(
                        'memory-limit',
                        'Set a specific memory limit for the script, '
-                               . '"max" for no limit or "default" to avoid changing it'
+                               . '"max" for no limit or "default" to avoid changing it',
+                       false,
+                       true
                );
                $this->addOption( 'server', "The protocol and server name to use in URLs, e.g. " .
                        "http://en.wikipedia.org. This is sometimes necessary because " .
@@@ -1593,12 -1594,12 +1595,12 @@@
                // something that can do the relevant syscalls. There are a few
                // options. Linux and Mac OS X both have "stty size" which does the
                // job directly.
 -              $retval = false;
 -              $size = wfShellExec( 'stty size', $retval );
 -              if ( $retval !== 0 ) {
 +              $result = Shell::command( 'stty', 'size' )
 +                      ->execute();
 +              if ( $result->getExitCode() !== 0 ) {
                        return $default;
                }
 -              if ( !preg_match( '/^(\d+) (\d+)$/', $size, $m ) ) {
 +              if ( !preg_match( '/^(\d+) (\d+)$/', $result->getStdout(), $m ) ) {
                        return $default;
                }
                return [ intval( $m[2] ), intval( $m[1] ) ];