rspec/rules/S6323/php/rule.adoc

== Why is this an issue?

include::../description.adoc[]

=== Noncompliant code example
[source,php]
----
preg_match("/Jack|Peter|/", "John"); // Noncompliant - returns 1
preg_match("/Jack||Peter/", "John"); // Noncompliant - returns 1
----
=== Compliant solution
[source,php]
----
preg_match("/Jack|Peter/", "John"); // returns 0
----

=== Exceptions

One could use an empty alternation to make a regular expression group optional. Note that the empty alternation should be the first or the last within the group, or else the rule will still report.

[source,php]
----
preg_match("/mandatory(|-optional)/", "mandatory"); // returns 1
preg_match("/mandatory(-optional|)/", "mandatory-optional"); // returns 1
----

However, if there is a quantifier after the group the issue will be reported as using both `|` and quantifier is redundant.

[source,php]
----
preg_match("/mandatory(-optional|)?/", "mandatory-optional"); // Noncompliant - using both `|` inside the group and `?` for the group.
----

include::../implementation.adoc[]