False positive: local scope static variables are mislabled as undefined when accessed

[ikari7789]

• PHPMD version: 2.10.2
• PHP Version: 7.2.34
• Installation type: composer
• Operating System / Distribution & Version: macOS 11.6

Current Behavior

The clean code UndefinedVariable rule reports a violation on local scope static variables.

FILE: /path/to/example.php
--------------------------------------------------------------------------------------------------------
 7   | VIOLATION | Avoid using undefined variables such as '$variable' which will lead to PHP notices.

Expected Behavior

Variable should be seen as defined and not report any violations.

Steps To Reproduce:

<?xml version="1.0"?>
<ruleset name="PHP Mess Detector Ruleset"
    xmlns="http://pmd.sf.net/ruleset/1.0.0"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://pmd.sf.net/ruleset/1.0.0 http://pmd.sf.net/ruleset_xml_schema.xsd"
    xsi:noNamespaceSchemaLocation="http://pmd.sf.net/ruleset_xml_schema.xsd">

    <rule ref="rulesets/cleancode.xml/UndefinedVariable" />
</ruleset>

<?php

function staticVariableUndefined()
{
    static $variable = 0;

    ++$variable;
}

phpmd example.php ansi example.xml

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