An preg_replace call always performs an evaluation of the first argument as a regular expression, even if no regular expression
features were used. This has a significant performance cost and therefore should be used with care.
When preg_replace is used, the first argument should be a real regular expression. If it’s not the case, str_replace does
exactly the same thing as preg_replace without the performance drawback of the regex.
This rule raises an issue for each preg_replace used with a simple string as first argument which doesn’t contains special regex
character or pattern.
Noncompliant code example
$str = "Bob is a Bird... Bob is a Plane... Bob is Superman!";
$changed = preg_replace("/Bob is/", "It's", $str); // Noncompliant
$changed = preg_replace("/\.\.\./", ";", $changed); // Noncompliant
Compliant solution
$str = "Bob is a Bird... Bob is a Plane... Bob is Superman!";
$changed = str_replace("Bob is", "It's", $str);
$changed = str_replace("...", ";", $changed);
Or, with a regex:
$str = "Bob is a Bird... Bob is a Plane... Bob is Superman!";
$changed = preg_replace("/\w*\sis/", "It's", $str);
$changed = preg_replace("/\.{3}/", ";", $changed);
