<?php
/*
* This file is part of PHPUnit.
*
* (c) Sebastian Bergmann <sebastian@phpunit.de>
*
* For the full copyright and license information, please view the LICENSE
* file that was distributed with this source code.
*/
namespace PHPUnit\Framework\Constraint;
/**
* Constraint that accepts null.
*/
class IsNull extends Constraint
{
/**
* Evaluates the constraint for parameter $other. Returns true if the
* constraint is met, false otherwise.
*
* @param mixed $other Value or object to evaluate.
*
* @return bool
*/
protected function matches($other)
{
return $other === null;
}
/**
* Returns a string representation of the constraint.
*
* @return string
*/
public function toString()
{
return 'is null';
}
}