Method setupUninstall

/**
 * Method to do any prechecks and setup the uninstall job
 *
 * @return  void
 *
 * @since   4.0.0
 */
protected function setupUninstall()
{
    $manifestFile = JPATH_MANIFESTS . '/packages/' . $this->extension->element . '.xml';
    $manifest = new PackageManifest($manifestFile);
    // Set the package root path
    $this->parent->setPath('extension_root', JPATH_MANIFESTS . '/packages/' . $manifest->packagename);
    // Set the source path for compatibility with the API
    $this->parent->setPath('source', $this->parent->getPath('extension_root'));
    // Because packages may not have their own folders we cannot use the standard method of finding an installation manifest
    if (!file_exists($manifestFile)) {
        throw new \RuntimeException(Text::_('JLIB_INSTALLER_ERROR_PACK_UNINSTALL_MISSINGMANIFEST'));
    }
    $xml = simplexml_load_file($manifestFile);
    if (!$xml) {
        throw new \RuntimeException(Text::_('JLIB_INSTALLER_ERROR_PACK_UNINSTALL_LOAD_MANIFEST'));
    }
    // Check for a valid XML root tag.
    if ($xml->getName() !== 'extension') {
        throw new \RuntimeException(Text::_('JLIB_INSTALLER_ERROR_PACK_UNINSTALL_INVALID_MANIFEST'));
    }
    $this->setManifest($xml);
    // Attempt to load the language file; might have uninstall strings
    $this->loadLanguage(JPATH_SITE);
}