1.2.1300. Unused Trait In Class

A trait has been summoned in a class, but is not used. Traits may be used as a copy/paste of code, bringing a batch of methods and properties to a class. In the current case, the imported trait is never called. As such, it may be removed.

Currently, the analysis covers only traits that are used in the class where they are imported. Also, the properties are not covered yet.

There are some sneaky situations, where a trait falls into decay : for example, creating a method in the importing class, with the name of a trait class, will exclude the trait method, as the class method has priority. Other precedence rules may lead to the same effect.

<?php

trait t {
    function foo() { return 1;}
}

// this class imports and uses the trait
class UsingTrait {
    use t;

    function bar() {
        return $this->foo() + 1;
    }
}

// this class imports but doesn't uses the trait
class UsingTrait {
    use t;

    function bar() {
        return 1;
    }
}

?>

See also Traits.

1.2.1300.1. Suggestions

• Remove the trait from the class

• Actually use the trait, at least in the importing class

• Use conflict resolution to make the trait accessible

1.2.1300.2. Specs

Short name	Traits/UnusedClassTrait
Rulesets	All, Changed Behavior, Class Review
Exakat since	2.1.1
PHP Version	All
Severity	Minor
Time To Fix	Quick (30 mins)
Precision	High
Features	trait
Available in	Entreprise Edition, Exakat Cloud