<?php
/*
* This file is part of the Symfony package.
*
* (c) Fabien Potencier <fabien@symfony.com>
*
* For the full copyright and license information, please view the LICENSE
* file that was distributed with this source code.
*/
namespace Symfony\Component\CssSelector\XPath\Extension;
use Symfony\Component\CssSelector\Exception\ExpressionErrorException;
use Symfony\Component\CssSelector\XPath\XPathExpr;
/**
* XPath expression translator pseudo-class extension.
*
* This component is a port of the Python cssselect library,
* which is copyright Ian Bicking, @see https://github.com/SimonSapin/cssselect.
*
* @author Jean-François Simon <jeanfrancois.simon@sensiolabs.com>
*
* @internal
*/
class PseudoClassExtension extends AbstractExtension
{
/**
* {@inheritdoc}
*/
public function getPseudoClassTranslators()
{
return [
'root' => [$this, 'translateRoot'],
'first-child' => [$this, 'translateFirstChild'],
'last-child' => [$this, 'translateLastChild'],
'first-of-type' => [$this, 'translateFirstOfType'],
'last-of-type' => [$this, 'translateLastOfType'],
'only-child' => [$this, 'translateOnlyChild'],
'only-of-type' => [$this, 'translateOnlyOfType'],
'empty' => [$this, 'translateEmpty'],
];
}
/**
* @return XPathExpr
*/
public function translateRoot(XPathExpr $xpath)
{
return $xpath->addCondition('not(parent::*)');
}
/**
* @return XPathExpr
*/
public function translateFirstChild(XPathExpr $xpath)
{
return $xpath
->addStarPrefix()
->addNameTest()
->addCondition('position() = 1');
}
/**
* @return XPathExpr
*/
public function translateLastChild(XPathExpr $xpath)
{
return $xpath
->addStarPrefix()
->addNameTest()
->addCondition('position() = last()');
}
/**
* @return XPathExpr
*
* @throws ExpressionErrorException
*/
public function translateFirstOfType(XPathExpr $xpath)
{
if ('*' === $xpath->getElement()) {
throw new ExpressionErrorException('"*:first-of-type" is not implemented.');
}
return $xpath
->addStarPrefix()
->addCondition('position() = 1');
}
/**
* @return XPathExpr
*
* @throws ExpressionErrorException
*/
public function translateLastOfType(XPathExpr $xpath)
{
if ('*' === $xpath->getElement()) {
throw new ExpressionErrorException('"*:last-of-type" is not implemented.');
}
return $xpath
->addStarPrefix()
->addCondition('position() = last()');
}
/**
* @return XPathExpr
*/
public function translateOnlyChild(XPathExpr $xpath)
{
return $xpath
->addStarPrefix()
->addNameTest()
->addCondition('last() = 1');
}
/**
* @return XPathExpr
*
* @throws ExpressionErrorException
*/
public function translateOnlyOfType(XPathExpr $xpath)
{
$element = $xpath->getElement();
if ('*' === $element) {
throw new ExpressionErrorException('"*:only-of-type" is not implemented.');
}
return $xpath->addCondition(sprintf('count(preceding-sibling::%s)=0 and count(following-sibling::%s)=0', $element, $element));
}
/**
* @return XPathExpr
*/
public function translateEmpty(XPathExpr $xpath)
{
return $xpath->addCondition('not(*) and not(string-length())');
}
/**
* {@inheritdoc}
*/
public function getName()
{
return 'pseudo-class';
}
}