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class Crawler in Zircon Profile 8

Same name and namespace in other branches
  1. 8.0 vendor/symfony/dom-crawler/Crawler.php \Symfony\Component\DomCrawler\Crawler

Crawler eases navigation of a list of \DOMElement objects.

@author Fabien Potencier <fabien@symfony.com>

Hierarchy

  • class \Symfony\Component\DomCrawler\Crawler extends \Symfony\Component\DomCrawler\SplObjectStorage

Expanded class hierarchy of Crawler

3 files declare their use of Crawler
BrowserKitDriver.php in vendor/behat/mink-browserkit-driver/src/BrowserKitDriver.php
Client.php in vendor/symfony/browser-kit/Client.php
CrawlerTest.php in vendor/symfony/dom-crawler/Tests/CrawlerTest.php

File

vendor/symfony/dom-crawler/Crawler.php, line 21

Namespace

Symfony\Component\DomCrawler
View source
class Crawler extends \SplObjectStorage {

  /**
   * @var string The current URI
   */
  protected $uri;

  /**
   * @var string The default namespace prefix to be used with XPath and CSS expressions
   */
  private $defaultNamespacePrefix = 'default';

  /**
   * @var array A map of manually registered namespaces
   */
  private $namespaces = array();

  /**
   * @var string The base href value
   */
  private $baseHref;

  /**
   * Constructor.
   *
   * @param mixed  $node       A Node to use as the base for the crawling
   * @param string $currentUri The current URI
   * @param string $baseHref   The base href value
   */
  public function __construct($node = null, $currentUri = null, $baseHref = null) {
    $this->uri = $currentUri;
    $this->baseHref = $baseHref ?: $currentUri;
    $this
      ->add($node);
  }

  /**
   * Removes all the nodes.
   */
  public function clear() {
    $this
      ->removeAll($this);
  }

  /**
   * Adds a node to the current list of nodes.
   *
   * This method uses the appropriate specialized add*() method based
   * on the type of the argument.
   *
   * @param \DOMNodeList|\DOMNode|array|string|null $node A node
   *
   * @throws \InvalidArgumentException When node is not the expected type.
   */
  public function add($node) {
    if ($node instanceof \DOMNodeList) {
      $this
        ->addNodeList($node);
    }
    elseif ($node instanceof \DOMNode) {
      $this
        ->addNode($node);
    }
    elseif (is_array($node)) {
      $this
        ->addNodes($node);
    }
    elseif (is_string($node)) {
      $this
        ->addContent($node);
    }
    elseif (null !== $node) {
      throw new \InvalidArgumentException(sprintf('Expecting a DOMNodeList or DOMNode instance, an array, a string, or null, but got "%s".', is_object($node) ? get_class($node) : gettype($node)));
    }
  }

  /**
   * Adds HTML/XML content.
   *
   * If the charset is not set via the content type, it is assumed
   * to be ISO-8859-1, which is the default charset defined by the
   * HTTP 1.1 specification.
   *
   * @param string      $content A string to parse as HTML/XML
   * @param null|string $type    The content type of the string
   */
  public function addContent($content, $type = null) {
    if (empty($type)) {
      $type = 0 === strpos($content, '<?xml') ? 'application/xml' : 'text/html';
    }

    // DOM only for HTML/XML content
    if (!preg_match('/(x|ht)ml/i', $type, $xmlMatches)) {
      return;
    }
    $charset = null;
    if (false !== ($pos = stripos($type, 'charset='))) {
      $charset = substr($type, $pos + 8);
      if (false !== ($pos = strpos($charset, ';'))) {
        $charset = substr($charset, 0, $pos);
      }
    }

    // http://www.w3.org/TR/encoding/#encodings
    // http://www.w3.org/TR/REC-xml/#NT-EncName
    if (null === $charset && preg_match('/\\<meta[^\\>]+charset *= *["\']?([a-zA-Z\\-0-9_:.]+)/i', $content, $matches)) {
      $charset = $matches[1];
    }
    if (null === $charset) {
      $charset = 'ISO-8859-1';
    }
    if ('x' === $xmlMatches[1]) {
      $this
        ->addXmlContent($content, $charset);
    }
    else {
      $this
        ->addHtmlContent($content, $charset);
    }
  }

  /**
   * Adds an HTML content to the list of nodes.
   *
   * The libxml errors are disabled when the content is parsed.
   *
   * If you want to get parsing errors, be sure to enable
   * internal errors via libxml_use_internal_errors(true)
   * and then, get the errors via libxml_get_errors(). Be
   * sure to clear errors with libxml_clear_errors() afterward.
   *
   * @param string $content The HTML content
   * @param string $charset The charset
   */
  public function addHtmlContent($content, $charset = 'UTF-8') {
    $internalErrors = libxml_use_internal_errors(true);
    $disableEntities = libxml_disable_entity_loader(true);
    $dom = new \DOMDocument('1.0', $charset);
    $dom->validateOnParse = true;
    set_error_handler(function () {
      throw new \Exception();
    });
    try {

      // Convert charset to HTML-entities to work around bugs in DOMDocument::loadHTML()
      if (function_exists('mb_convert_encoding')) {
        $content = mb_convert_encoding($content, 'HTML-ENTITIES', $charset);
      }
      elseif (function_exists('iconv')) {
        $content = preg_replace_callback('/[\\x80-\\xFF]+/', function ($m) {
          $m = unpack('C*', $m[0]);
          $i = 1;
          $entities = '';
          while (isset($m[$i])) {
            if (0xf0 <= $m[$i]) {
              $c = ($m[$i++] - 0xf0 << 18) + ($m[$i++] - 0x80 << 12) + ($m[$i++] - 0x80 << 6) + $m[$i++] - 0x80;
            }
            elseif (0xe0 <= $m[$i]) {
              $c = ($m[$i++] - 0xe0 << 12) + ($m[$i++] - 0x80 << 6) + $m[$i++] - 0x80;
            }
            else {
              $c = ($m[$i++] - 0xc0 << 6) + $m[$i++] - 0x80;
            }
            $entities .= '&#' . $c . ';';
          }
          return $entities;
        }, iconv($charset, 'UTF-8', $content));
      }
    } catch (\Exception $e) {
    }
    restore_error_handler();
    if ('' !== trim($content)) {
      @$dom
        ->loadHTML($content);
    }
    libxml_use_internal_errors($internalErrors);
    libxml_disable_entity_loader($disableEntities);
    $this
      ->addDocument($dom);
    $base = $this
      ->filterRelativeXPath('descendant-or-self::base')
      ->extract(array(
      'href',
    ));
    $baseHref = current($base);
    if (count($base) && !empty($baseHref)) {
      if ($this->baseHref) {
        $linkNode = $dom
          ->createElement('a');
        $linkNode
          ->setAttribute('href', $baseHref);
        $link = new Link($linkNode, $this->baseHref);
        $this->baseHref = $link
          ->getUri();
      }
      else {
        $this->baseHref = $baseHref;
      }
    }
  }

  /**
   * Adds an XML content to the list of nodes.
   *
   * The libxml errors are disabled when the content is parsed.
   *
   * If you want to get parsing errors, be sure to enable
   * internal errors via libxml_use_internal_errors(true)
   * and then, get the errors via libxml_get_errors(). Be
   * sure to clear errors with libxml_clear_errors() afterward.
   *
   * @param string $content The XML content
   * @param string $charset The charset
   */
  public function addXmlContent($content, $charset = 'UTF-8') {

    // remove the default namespace if it's the only namespace to make XPath expressions simpler
    if (!preg_match('/xmlns:/', $content)) {
      $content = str_replace('xmlns', 'ns', $content);
    }
    $internalErrors = libxml_use_internal_errors(true);
    $disableEntities = libxml_disable_entity_loader(true);
    $dom = new \DOMDocument('1.0', $charset);
    $dom->validateOnParse = true;
    if ('' !== trim($content)) {
      @$dom
        ->loadXML($content, LIBXML_NONET);
    }
    libxml_use_internal_errors($internalErrors);
    libxml_disable_entity_loader($disableEntities);
    $this
      ->addDocument($dom);
  }

  /**
   * Adds a \DOMDocument to the list of nodes.
   *
   * @param \DOMDocument $dom A \DOMDocument instance
   */
  public function addDocument(\DOMDocument $dom) {
    if ($dom->documentElement) {
      $this
        ->addNode($dom->documentElement);
    }
  }

  /**
   * Adds a \DOMNodeList to the list of nodes.
   *
   * @param \DOMNodeList $nodes A \DOMNodeList instance
   */
  public function addNodeList(\DOMNodeList $nodes) {
    foreach ($nodes as $node) {
      if ($node instanceof \DOMNode) {
        $this
          ->addNode($node);
      }
    }
  }

  /**
   * Adds an array of \DOMNode instances to the list of nodes.
   *
   * @param \DOMNode[] $nodes An array of \DOMNode instances
   */
  public function addNodes(array $nodes) {
    foreach ($nodes as $node) {
      $this
        ->add($node);
    }
  }

  /**
   * Adds a \DOMNode instance to the list of nodes.
   *
   * @param \DOMNode $node A \DOMNode instance
   */
  public function addNode(\DOMNode $node) {
    if ($node instanceof \DOMDocument) {
      $this
        ->attach($node->documentElement);
    }
    else {
      $this
        ->attach($node);
    }
  }

  // Serializing and unserializing a crawler creates DOM objects in a corrupted state. DOM elements are not properly serializable.
  public function unserialize($serialized) {
    throw new \BadMethodCallException('A Crawler cannot be serialized.');
  }
  public function serialize() {
    throw new \BadMethodCallException('A Crawler cannot be serialized.');
  }

  /**
   * Returns a node given its position in the node list.
   *
   * @param int $position The position
   *
   * @return Crawler A new instance of the Crawler with the selected node, or an empty Crawler if it does not exist.
   */
  public function eq($position) {
    foreach ($this as $i => $node) {
      if ($i == $position) {
        return $this
          ->createSubCrawler($node);
      }
    }
    return $this
      ->createSubCrawler(null);
  }

  /**
   * Calls an anonymous function on each node of the list.
   *
   * The anonymous function receives the position and the node wrapped
   * in a Crawler instance as arguments.
   *
   * Example:
   *
   *     $crawler->filter('h1')->each(function ($node, $i) {
   *         return $node->text();
   *     });
   *
   * @param \Closure $closure An anonymous function
   *
   * @return array An array of values returned by the anonymous function
   */
  public function each(\Closure $closure) {
    $data = array();
    foreach ($this as $i => $node) {
      $data[] = $closure($this
        ->createSubCrawler($node), $i);
    }
    return $data;
  }

  /**
   * Slices the list of nodes by $offset and $length.
   *
   * @param int $offset
   * @param int $length
   *
   * @return Crawler A Crawler instance with the sliced nodes
   */
  public function slice($offset = 0, $length = -1) {
    return $this
      ->createSubCrawler(iterator_to_array(new \LimitIterator($this, $offset, $length)));
  }

  /**
   * Reduces the list of nodes by calling an anonymous function.
   *
   * To remove a node from the list, the anonymous function must return false.
   *
   * @param \Closure $closure An anonymous function
   *
   * @return Crawler A Crawler instance with the selected nodes.
   */
  public function reduce(\Closure $closure) {
    $nodes = array();
    foreach ($this as $i => $node) {
      if (false !== $closure($this
        ->createSubCrawler($node), $i)) {
        $nodes[] = $node;
      }
    }
    return $this
      ->createSubCrawler($nodes);
  }

  /**
   * Returns the first node of the current selection.
   *
   * @return Crawler A Crawler instance with the first selected node
   */
  public function first() {
    return $this
      ->eq(0);
  }

  /**
   * Returns the last node of the current selection.
   *
   * @return Crawler A Crawler instance with the last selected node
   */
  public function last() {
    return $this
      ->eq(count($this) - 1);
  }

  /**
   * Returns the siblings nodes of the current selection.
   *
   * @return Crawler A Crawler instance with the sibling nodes
   *
   * @throws \InvalidArgumentException When current node is empty
   */
  public function siblings() {
    if (!count($this)) {
      throw new \InvalidArgumentException('The current node list is empty.');
    }
    return $this
      ->createSubCrawler($this
      ->sibling($this
      ->getNode(0)->parentNode->firstChild));
  }

  /**
   * Returns the next siblings nodes of the current selection.
   *
   * @return Crawler A Crawler instance with the next sibling nodes
   *
   * @throws \InvalidArgumentException When current node is empty
   */
  public function nextAll() {
    if (!count($this)) {
      throw new \InvalidArgumentException('The current node list is empty.');
    }
    return $this
      ->createSubCrawler($this
      ->sibling($this
      ->getNode(0)));
  }

  /**
   * Returns the previous sibling nodes of the current selection.
   *
   * @return Crawler A Crawler instance with the previous sibling nodes
   *
   * @throws \InvalidArgumentException
   */
  public function previousAll() {
    if (!count($this)) {
      throw new \InvalidArgumentException('The current node list is empty.');
    }
    return $this
      ->createSubCrawler($this
      ->sibling($this
      ->getNode(0), 'previousSibling'));
  }

  /**
   * Returns the parents nodes of the current selection.
   *
   * @return Crawler A Crawler instance with the parents nodes of the current selection
   *
   * @throws \InvalidArgumentException When current node is empty
   */
  public function parents() {
    if (!count($this)) {
      throw new \InvalidArgumentException('The current node list is empty.');
    }
    $node = $this
      ->getNode(0);
    $nodes = array();
    while ($node = $node->parentNode) {
      if (1 === $node->nodeType) {
        $nodes[] = $node;
      }
    }
    return $this
      ->createSubCrawler($nodes);
  }

  /**
   * Returns the children nodes of the current selection.
   *
   * @return Crawler A Crawler instance with the children nodes
   *
   * @throws \InvalidArgumentException When current node is empty
   */
  public function children() {
    if (!count($this)) {
      throw new \InvalidArgumentException('The current node list is empty.');
    }
    $node = $this
      ->getNode(0)->firstChild;
    return $this
      ->createSubCrawler($node ? $this
      ->sibling($node) : array());
  }

  /**
   * Returns the attribute value of the first node of the list.
   *
   * @param string $attribute The attribute name
   *
   * @return string|null The attribute value or null if the attribute does not exist
   *
   * @throws \InvalidArgumentException When current node is empty
   */
  public function attr($attribute) {
    if (!count($this)) {
      throw new \InvalidArgumentException('The current node list is empty.');
    }
    $node = $this
      ->getNode(0);
    return $node
      ->hasAttribute($attribute) ? $node
      ->getAttribute($attribute) : null;
  }

  /**
   * Returns the node name of the first node of the list.
   *
   * @return string The node name
   *
   * @throws \InvalidArgumentException When current node is empty
   */
  public function nodeName() {
    if (!count($this)) {
      throw new \InvalidArgumentException('The current node list is empty.');
    }
    return $this
      ->getNode(0)->nodeName;
  }

  /**
   * Returns the node value of the first node of the list.
   *
   * @return string The node value
   *
   * @throws \InvalidArgumentException When current node is empty
   */
  public function text() {
    if (!count($this)) {
      throw new \InvalidArgumentException('The current node list is empty.');
    }
    return $this
      ->getNode(0)->nodeValue;
  }

  /**
   * Returns the first node of the list as HTML.
   *
   * @return string The node html
   *
   * @throws \InvalidArgumentException When current node is empty
   */
  public function html() {
    if (!count($this)) {
      throw new \InvalidArgumentException('The current node list is empty.');
    }
    $html = '';
    foreach ($this
      ->getNode(0)->childNodes as $child) {
      $html .= $child->ownerDocument
        ->saveHTML($child);
    }
    return $html;
  }

  /**
   * Extracts information from the list of nodes.
   *
   * You can extract attributes or/and the node value (_text).
   *
   * Example:
   *
   * $crawler->filter('h1 a')->extract(array('_text', 'href'));
   *
   * @param array $attributes An array of attributes
   *
   * @return array An array of extracted values
   */
  public function extract($attributes) {
    $attributes = (array) $attributes;
    $count = count($attributes);
    $data = array();
    foreach ($this as $node) {
      $elements = array();
      foreach ($attributes as $attribute) {
        if ('_text' === $attribute) {
          $elements[] = $node->nodeValue;
        }
        else {
          $elements[] = $node
            ->getAttribute($attribute);
        }
      }
      $data[] = $count > 1 ? $elements : $elements[0];
    }
    return $data;
  }

  /**
   * Filters the list of nodes with an XPath expression.
   *
   * The XPath expression is evaluated in the context of the crawler, which
   * is considered as a fake parent of the elements inside it.
   * This means that a child selector "div" or "./div" will match only
   * the div elements of the current crawler, not their children.
   *
   * @param string $xpath An XPath expression
   *
   * @return Crawler A new instance of Crawler with the filtered list of nodes
   */
  public function filterXPath($xpath) {
    $xpath = $this
      ->relativize($xpath);

    // If we dropped all expressions in the XPath while preparing it, there would be no match
    if ('' === $xpath) {
      return $this
        ->createSubCrawler(null);
    }
    return $this
      ->filterRelativeXPath($xpath);
  }

  /**
   * Filters the list of nodes with a CSS selector.
   *
   * This method only works if you have installed the CssSelector Symfony Component.
   *
   * @param string $selector A CSS selector
   *
   * @return Crawler A new instance of Crawler with the filtered list of nodes
   *
   * @throws \RuntimeException if the CssSelector Component is not available
   */
  public function filter($selector) {
    if (!class_exists('Symfony\\Component\\CssSelector\\CssSelector')) {
      throw new \RuntimeException('Unable to filter with a CSS selector as the Symfony CssSelector is not installed (you can use filterXPath instead).');
    }

    // The CssSelector already prefixes the selector with descendant-or-self::
    return $this
      ->filterRelativeXPath(CssSelector::toXPath($selector));
  }

  /**
   * Selects links by name or alt value for clickable images.
   *
   * @param string $value The link text
   *
   * @return Crawler A new instance of Crawler with the filtered list of nodes
   */
  public function selectLink($value) {
    $xpath = sprintf('descendant-or-self::a[contains(concat(\' \', normalize-space(string(.)), \' \'), %s) ', static::xpathLiteral(' ' . $value . ' ')) . sprintf('or ./img[contains(concat(\' \', normalize-space(string(@alt)), \' \'), %s)]]', static::xpathLiteral(' ' . $value . ' '));
    return $this
      ->filterRelativeXPath($xpath);
  }

  /**
   * Selects a button by name or alt value for images.
   *
   * @param string $value The button text
   *
   * @return Crawler A new instance of Crawler with the filtered list of nodes
   */
  public function selectButton($value) {
    $translate = 'translate(@type, "ABCDEFGHIJKLMNOPQRSTUVWXYZ", "abcdefghijklmnopqrstuvwxyz")';
    $xpath = sprintf('descendant-or-self::input[((contains(%s, "submit") or contains(%s, "button")) and contains(concat(\' \', normalize-space(string(@value)), \' \'), %s)) ', $translate, $translate, static::xpathLiteral(' ' . $value . ' ')) . sprintf('or (contains(%s, "image") and contains(concat(\' \', normalize-space(string(@alt)), \' \'), %s)) or @id=%s or @name=%s] ', $translate, static::xpathLiteral(' ' . $value . ' '), static::xpathLiteral($value), static::xpathLiteral($value)) . sprintf('| descendant-or-self::button[contains(concat(\' \', normalize-space(string(.)), \' \'), %s) or @id=%s or @name=%s]', static::xpathLiteral(' ' . $value . ' '), static::xpathLiteral($value), static::xpathLiteral($value));
    return $this
      ->filterRelativeXPath($xpath);
  }

  /**
   * Returns a Link object for the first node in the list.
   *
   * @param string $method The method for the link (get by default)
   *
   * @return Link A Link instance
   *
   * @throws \InvalidArgumentException If the current node list is empty
   */
  public function link($method = 'get') {
    if (!count($this)) {
      throw new \InvalidArgumentException('The current node list is empty.');
    }
    $node = $this
      ->getNode(0);
    return new Link($node, $this->baseHref, $method);
  }

  /**
   * Returns an array of Link objects for the nodes in the list.
   *
   * @return Link[] An array of Link instances
   */
  public function links() {
    $links = array();
    foreach ($this as $node) {
      $links[] = new Link($node, $this->baseHref, 'get');
    }
    return $links;
  }

  /**
   * Returns a Form object for the first node in the list.
   *
   * @param array  $values An array of values for the form fields
   * @param string $method The method for the form
   *
   * @return Form A Form instance
   *
   * @throws \InvalidArgumentException If the current node list is empty
   */
  public function form(array $values = null, $method = null) {
    if (!count($this)) {
      throw new \InvalidArgumentException('The current node list is empty.');
    }
    $form = new Form($this
      ->getNode(0), $this->uri, $method, $this->baseHref);
    if (null !== $values) {
      $form
        ->setValues($values);
    }
    return $form;
  }

  /**
   * Overloads a default namespace prefix to be used with XPath and CSS expressions.
   *
   * @param string $prefix
   */
  public function setDefaultNamespacePrefix($prefix) {
    $this->defaultNamespacePrefix = $prefix;
  }

  /**
   * @param string $prefix
   * @param string $namespace
   */
  public function registerNamespace($prefix, $namespace) {
    $this->namespaces[$prefix] = $namespace;
  }

  /**
   * Converts string for XPath expressions.
   *
   * Escaped characters are: quotes (") and apostrophe (').
   *
   *  Examples:
   *  <code>
   *     echo Crawler::xpathLiteral('foo " bar');
   *     //prints 'foo " bar'
   *
   *     echo Crawler::xpathLiteral("foo ' bar");
   *     //prints "foo ' bar"
   *
   *     echo Crawler::xpathLiteral('a\'b"c');
   *     //prints concat('a', "'", 'b"c')
   *  </code>
   *
   * @param string $s String to be escaped
   *
   * @return string Converted string
   */
  public static function xpathLiteral($s) {
    if (false === strpos($s, "'")) {
      return sprintf("'%s'", $s);
    }
    if (false === strpos($s, '"')) {
      return sprintf('"%s"', $s);
    }
    $string = $s;
    $parts = array();
    while (true) {
      if (false !== ($pos = strpos($string, "'"))) {
        $parts[] = sprintf("'%s'", substr($string, 0, $pos));
        $parts[] = "\"'\"";
        $string = substr($string, $pos + 1);
      }
      else {
        $parts[] = "'{$string}'";
        break;
      }
    }
    return sprintf('concat(%s)', implode($parts, ', '));
  }

  /**
   * Filters the list of nodes with an XPath expression.
   *
   * The XPath expression should already be processed to apply it in the context of each node.
   *
   * @param string $xpath
   *
   * @return Crawler
   */
  private function filterRelativeXPath($xpath) {
    $prefixes = $this
      ->findNamespacePrefixes($xpath);
    $crawler = $this
      ->createSubCrawler(null);
    foreach ($this as $node) {
      $domxpath = $this
        ->createDOMXPath($node->ownerDocument, $prefixes);
      $crawler
        ->add($domxpath
        ->query($xpath, $node));
    }
    return $crawler;
  }

  /**
   * Make the XPath relative to the current context.
   *
   * The returned XPath will match elements matching the XPath inside the current crawler
   * when running in the context of a node of the crawler.
   *
   * @param string $xpath
   *
   * @return string
   */
  private function relativize($xpath) {
    $expressions = array();
    $unionPattern = '/\\|(?![^\\[]*\\])/';

    // An expression which will never match to replace expressions which cannot match in the crawler
    // We cannot simply drop
    $nonMatchingExpression = 'a[name() = "b"]';

    // Split any unions into individual expressions.
    foreach (preg_split($unionPattern, $xpath) as $expression) {
      $expression = trim($expression);
      $parenthesis = '';

      // If the union is inside some braces, we need to preserve the opening braces and apply
      // the change only inside it.
      if (preg_match('/^[\\(\\s*]+/', $expression, $matches)) {
        $parenthesis = $matches[0];
        $expression = substr($expression, strlen($parenthesis));
      }

      // BC for Symfony 2.4 and lower were elements were adding in a fake _root parent
      if (0 === strpos($expression, '/_root/')) {
        $expression = './' . substr($expression, 7);
      }
      elseif (0 === strpos($expression, 'self::*/')) {
        $expression = './' . substr($expression, 8);
      }

      // add prefix before absolute element selector
      if (empty($expression)) {
        $expression = $nonMatchingExpression;
      }
      elseif (0 === strpos($expression, '//')) {
        $expression = 'descendant-or-self::' . substr($expression, 2);
      }
      elseif (0 === strpos($expression, './/')) {
        $expression = 'descendant-or-self::' . substr($expression, 3);
      }
      elseif (0 === strpos($expression, './')) {
        $expression = 'self::' . substr($expression, 2);
      }
      elseif (0 === strpos($expression, 'child::')) {
        $expression = 'self::' . substr($expression, 7);
      }
      elseif ('/' === $expression[0] || 0 === strpos($expression, 'self::')) {

        // the only direct child in Symfony 2.4 and lower is _root, which is already handled previously
        // so let's drop the expression entirely
        $expression = $nonMatchingExpression;
      }
      elseif ('.' === $expression[0]) {

        // '.' is the fake root element in Symfony 2.4 and lower, which is excluded from results
        $expression = $nonMatchingExpression;
      }
      elseif (0 === strpos($expression, 'descendant::')) {
        $expression = 'descendant-or-self::' . substr($expression, strlen('descendant::'));
      }
      elseif (preg_match('/^(ancestor|ancestor-or-self|attribute|following|following-sibling|namespace|parent|preceding|preceding-sibling)::/', $expression)) {

        // the fake root has no parent, preceding or following nodes and also no attributes (even no namespace attributes)
        $expression = $nonMatchingExpression;
      }
      elseif (0 !== strpos($expression, 'descendant-or-self::')) {
        $expression = 'self::' . $expression;
      }
      $expressions[] = $parenthesis . $expression;
    }
    return implode(' | ', $expressions);
  }

  /**
   * @param int $position
   *
   * @return \DOMElement|null
   */
  public function getNode($position) {
    foreach ($this as $i => $node) {
      if ($i == $position) {
        return $node;
      }
    }
  }

  /**
   * @param \DOMElement $node
   * @param string      $siblingDir
   *
   * @return array
   */
  protected function sibling($node, $siblingDir = 'nextSibling') {
    $nodes = array();
    do {
      if ($node !== $this
        ->getNode(0) && $node->nodeType === 1) {
        $nodes[] = $node;
      }
    } while ($node = $node->{$siblingDir});
    return $nodes;
  }

  /**
   * @param \DOMDocument $document
   * @param array        $prefixes
   *
   * @return \DOMXPath
   *
   * @throws \InvalidArgumentException
   */
  private function createDOMXPath(\DOMDocument $document, array $prefixes = array()) {
    $domxpath = new \DOMXPath($document);
    foreach ($prefixes as $prefix) {
      $namespace = $this
        ->discoverNamespace($domxpath, $prefix);
      if (null !== $namespace) {
        $domxpath
          ->registerNamespace($prefix, $namespace);
      }
    }
    return $domxpath;
  }

  /**
   * @param \DOMXPath $domxpath
   * @param string    $prefix
   *
   * @return string
   *
   * @throws \InvalidArgumentException
   */
  private function discoverNamespace(\DOMXPath $domxpath, $prefix) {
    if (isset($this->namespaces[$prefix])) {
      return $this->namespaces[$prefix];
    }

    // ask for one namespace, otherwise we'd get a collection with an item for each node
    $namespaces = $domxpath
      ->query(sprintf('(//namespace::*[name()="%s"])[last()]', $this->defaultNamespacePrefix === $prefix ? '' : $prefix));
    if ($node = $namespaces
      ->item(0)) {
      return $node->nodeValue;
    }
  }

  /**
   * @param string $xpath
   *
   * @return array
   */
  private function findNamespacePrefixes($xpath) {
    if (preg_match_all('/(?P<prefix>[a-z_][a-z_0-9\\-\\.]*+):[^"\\/:]/i', $xpath, $matches)) {
      return array_unique($matches['prefix']);
    }
    return array();
  }

  /**
   * Creates a crawler for some subnodes.
   *
   * @param \DOMElement|\DOMElement[]|\DOMNodeList|null $nodes
   *
   * @return static
   */
  private function createSubCrawler($nodes) {
    $crawler = new static($nodes, $this->uri, $this->baseHref);
    return $crawler;
  }

}

Members

Namesort descending Modifiers Type Description Overrides
Crawler::$baseHref private property
Crawler::$defaultNamespacePrefix private property
Crawler::$namespaces private property
Crawler::$uri protected property
Crawler::add public function Adds a node to the current list of nodes.
Crawler::addContent public function Adds HTML/XML content.
Crawler::addDocument public function Adds a \DOMDocument to the list of nodes.
Crawler::addHtmlContent public function Adds an HTML content to the list of nodes.
Crawler::addNode public function Adds a \DOMNode instance to the list of nodes.
Crawler::addNodeList public function Adds a \DOMNodeList to the list of nodes.
Crawler::addNodes public function Adds an array of \DOMNode instances to the list of nodes.
Crawler::addXmlContent public function Adds an XML content to the list of nodes.
Crawler::attr public function Returns the attribute value of the first node of the list.
Crawler::children public function Returns the children nodes of the current selection.
Crawler::clear public function Removes all the nodes.
Crawler::createDOMXPath private function
Crawler::createSubCrawler private function Creates a crawler for some subnodes.
Crawler::discoverNamespace private function
Crawler::each public function Calls an anonymous function on each node of the list.
Crawler::eq public function Returns a node given its position in the node list.
Crawler::extract public function Extracts information from the list of nodes.
Crawler::filter public function Filters the list of nodes with a CSS selector.
Crawler::filterRelativeXPath private function Filters the list of nodes with an XPath expression.
Crawler::filterXPath public function Filters the list of nodes with an XPath expression.
Crawler::findNamespacePrefixes private function
Crawler::first public function Returns the first node of the current selection.
Crawler::form public function Returns a Form object for the first node in the list.
Crawler::getNode public function
Crawler::html public function Returns the first node of the list as HTML.
Crawler::last public function Returns the last node of the current selection.
Crawler::link public function Returns a Link object for the first node in the list.
Crawler::links public function Returns an array of Link objects for the nodes in the list.
Crawler::nextAll public function Returns the next siblings nodes of the current selection.
Crawler::nodeName public function Returns the node name of the first node of the list.
Crawler::parents public function Returns the parents nodes of the current selection.
Crawler::previousAll public function Returns the previous sibling nodes of the current selection.
Crawler::reduce public function Reduces the list of nodes by calling an anonymous function.
Crawler::registerNamespace public function
Crawler::relativize private function Make the XPath relative to the current context.
Crawler::selectButton public function Selects a button by name or alt value for images.
Crawler::selectLink public function Selects links by name or alt value for clickable images.
Crawler::serialize public function
Crawler::setDefaultNamespacePrefix public function Overloads a default namespace prefix to be used with XPath and CSS expressions.
Crawler::sibling protected function
Crawler::siblings public function Returns the siblings nodes of the current selection.
Crawler::slice public function Slices the list of nodes by $offset and $length.
Crawler::text public function Returns the node value of the first node of the list.
Crawler::unserialize public function
Crawler::xpathLiteral public static function Converts string for XPath expressions.
Crawler::__construct public function Constructor.