cmd.txt

$ phpcs --standard=WordPress-Core test.php

--------------------------------------------------------------------------------
FOUND 0 ERRORS AND 2 WARNINGS AFFECTING 2 LINES
--------------------------------------------------------------------------------
 5 | WARNING | Array keys should be surrounded by spaces unless they contain a
   |         | string or an integer.
 6 | WARNING | Array keys should NOT be surrounded by spaces if they only
   |         | contain a string or an integer.
--------------------------------------------------------------------------------

Time: 13ms; Memory: 2.5Mb

test.php

<?php

$arr = array( 1, 2, 3 );
$i = 0;
$x = $arr[$i];
$y = $arr[ 1 ];