On a PHP functions and methods, create a var without use it raise a "unnused" highlight on the editor, but this feature does not cat highlight variables ununsed but the publisher has not find cases of variables that were not used, but were used on allocations in a more than once time.

Examples:

<?php
function a()
{
  $test = 1; //highlight unnused var
}

function b()
{
  $test = 1;
  $test ++; //do not highlight $test
}
 
in practice, this variable is not being used because the assignment it is not serving.