1.2.264. Could Be Protected Class Constant

Class constant may use ‘protected’ visibility.

Since PHP 7.1, constants may also have a public/protected/private visibility. This restrict their usage to anywhere, class and children or class.

As a general rule, it is recommended to make constant ‘private’ by default, and to relax this restriction as needed. PHP makes them public by default.

<?php

class foo {
    // pre-7.1 style
    const PRE_71_CONSTANT = 1;

    // post-7.1 style
    protected const PROTECTED_CONSTANT = 2;
    public const PUBLIC_CONSTANT = 3;
}

class foo2 extends foo {
    function bar() {
        // PROTECTED_CONSTANT may only be used in its class or its children
        echo self::PROTECTED_CONSTANT;
    }
}

class foo3 extends foo {
    function bar() {
        // PROTECTED_CONSTANT may only be used in its class or any of its children
        echo self::PROTECTED_CONSTANT;
    }
}

// Other constants may be used anywhere
function x($a = foo::PUBLIC_CONSTANT) {
    echo $a.' '.foo:PRE_71_CONSTANT;
}

?>

1.2.264.1. Connex PHP features

• visibility

• class-constant

1.2.264.1.1. Suggestions

• Use protected visibility with the reported constants.

1.2.264.1.2. Specs

Short name	Classes/CouldBeProtectedConstant
Rulesets	All, Changed Behavior, Class Review
Exakat since	0.12.11
PHP Version	All
Severity	Minor
Time To Fix	Quick (30 mins)
Precision	Very high
Available in	Entreprise Edition, Exakat Cloud