framework/behaviors/AttributesBehavior.php
public function evaluateAttributes($event)
    {
        if ($this->skipUpdateOnClean
            && $event->name === ActiveRecord::EVENT_BEFORE_UPDATE
            && empty($this->owner->dirtyAttributes)
        ) {
            return;
        }
        $attributes = array_keys(array_filter($this->attributes, function ($carry) use ($event) {
            return array_key_exists($event->name, $carry);
        }));
        if (!empty($this->order[$event->name])) {
            $attributes = array_merge(
                array_intersect((array) $this->order[$event->name], $attributes),
                array_diff($attributes, (array) $this->order[$event->name]));
        }
        foreach ($attributes as $attribute) {
            if ($this->preserveNonEmptyValues && !empty($this->owner->$attribute)) {
                continue;
            }
            $this->owner->$attribute = $this->getValue($attribute, $event);
        }
    }
public function evaluateAttributes($event)
    {
        if ($this->skipUpdateOnClean
            && $event->name === ActiveRecord::EVENT_BEFORE_UPDATE
            && empty($this->owner->dirtyAttributes)
        ) {
            return;
        }
        $attributes = array_keys(array_filter($this->attributes, function ($carry) use ($event) {
            return array_key_exists($event->name, $carry);
        }));
        if (!empty($this->order[$event->name])) {
            $attributes = array_merge(
                array_intersect((array) $this->order[$event->name], $attributes),
                array_diff($attributes, (array) $this->order[$event->name]));
        }
        foreach ($attributes as $attribute) {
            if ($this->preserveNonEmptyValues && !empty($this->owner->$attribute)) {
                continue;
            }
            $this->owner->$attribute = $this->getValue($attribute, $event);
        }
    }
Evaluates the attributes values and assigns it to the current attributes.
@param Event $event