Magento 2 - where is method declaration of $this->getAddress() in Magento\Directory\Helper\Data line146

Question

where is method declaration of $this->getAddress() in https://github.com/magento/magento2/blob/develop/app/code/Magento/Directory/Helper/Data.php#L146

public function getRegionCollection()
{
    if (!$this->_regionCollection) {
        $this->_regionCollection = $this->_regCollectionFactory->create();
        $this->_regionCollection->addCountryFilter($this->getAddress()->getCountryId())->load();
    }
    return $this->_regionCollection;
}

i don't know where is method come from, but if i search "function getAddress()", i fount it in Magento\module-customer\Block\Address\Edit https://github.com/magento/magento2/blob/develop/app/code/Magento/Customer/Block/Address/Edit.php#L211

/**
 * Return the associated address.
 *
 * @return \Magento\Customer\Api\Data\AddressInterface
 */
public function getAddress()
{
    return $this->_address;
}

i don't think that class is related

Answer 1

It does not exist. Since it is not derived from the Data Object class there are also no magic methods available here.

The only reason this is not raising an error seems to be that this method is not used anywhere: https://github.com/magento/magento2/search?utf8=%E2%9C%93&q=getRegionCollection