PhpCsFixer\Fixer\ReturnNotation\SimplifiedNullReturnFixer::getDefinition PHP Method

    public function getDefinition()
    {
        return new FixerDefinition('A return statement wishing to return "void" should not return "null".', array(new CodeSample('<?php return null;')), null, null, null, 'Risky as of PHP 7.1 as since than a difference between returning "null" and "void" can be hinted as return type.');
    }