src/TaggableBehavior.php
protected function ownerHasTagAttribute()
    {
        if ($this->_hasTagAttribute === null) {
            $this->_hasTagAttribute = $this->owner->hasAttribute('tags');
        }
        return $this->_hasTagAttribute;
    }
protected function ownerHasTagAttribute()
    {
        if ($this->_hasTagAttribute === null) {
            $this->_hasTagAttribute = $this->owner->hasAttribute('tags');
        }
        return $this->_hasTagAttribute;
    }
check that the owner has the attribute `tags`
@return bool