Cloning objects should also clone their behaviors

[brandonkelly]

Currently, Component::__clone() will null-out the $_behaviors array:

yii2/framework/base/Component.php

Lines 307 to 312 in 3d96a45

	public function __clone()
	{
	$this->_events = [];
	$this->_eventWildcards = [];
	$this->_behaviors = null;
	}

I can see why this is better than leaving $_behaviors alone (those behaviors contain a reference to the original component instance), but I think it would be better if those behaviors were cloned to the new instance as well.

public function __clone()
{
    $this->_events = [];
    $this-> _eventWildcards = [];

    if ($this->_behaviors !== null) {
        $behaviors = array_merge($this->_behaviors);
        $this->_behaviors = null;
        foreach ($behaviors as $name => $behavior) {
            $this->attachBehavior($name, clone $behavior);
        }
}

That way any property values set on the behavior will be maintained on the cloned instance, just like normal properties.

$obj = new MyClassWithBehavior();
$obj->myBehaviorProperty = 'bar';
$obj2 = clone $obj;
echo $obj2->myBehaviorProperty; // should output 'bar'

(related: craftcms/cms#2857)

[samdark]

Yes. It's not backwards compatible and could be done in 2.1. Would you like to send a pull request?

[brandonkelly]

I figured it would be more of a 2.1 thing. Happy to submit a PR.

[brandonkelly]

@samdark ICYMI a PR was submitted for this (#16291).