To support readability, the equal signs may be aligned in block-related assignments:
<?php
$short = foo($bar);
$longer = foo($baz);
?>
The rule can be broken when the length of the variable name is at least 8 characters longer/shorter than the previous one:
<?php
$short = foo($bar);
$thisVariableNameIsVeeeeeeeeeeryLong = foo($baz);
?>