1--TEST-- 2Return type cannot add nullability (contravariance) 3--FILE-- 4<?php 5 6interface A { 7 function method(): int; 8} 9 10interface B extends A { 11 function method(): ?int; 12} 13--EXPECTF-- 14Fatal error: Declaration of B::method(): ?int must be compatible with A::method(): int in %s on line %d 15