1.2.1050. Results May Be Missing

preg_match() may return empty values, if the search fails. It is important to check for the existence of results before assigning them to another variable, or using it. Since PHP 7.2, it is possible to use the PREG_UNMATCHED_AS_NULL constant in the flag parameter to avoid this.

<?php
    preg_match('/PHP ([0-9\.]+) /', $res, $r);
    $s = $r[1];
    // $s may end up null if preg_match fails.
?>

1.2.1050.1. Suggestions

  • Use a final always capturing parenthesis to avoid this

  • Use the PREG_UNMATCHED_AS_NULL option (PHP 7.2)

1.2.1050.2. Specs

Short name

Structures/ResultMayBeMissing

Rulesets

All, Analyze, CE, CI-checks, Changed Behavior

Exakat since

0.8.4

PHP Version

All

Severity

Major

Time To Fix

Quick (30 mins)

Precision

Very high

Available in

Entreprise Edition, Community Edition, Exakat Cloud