third_party/web_platform_tests/domxpath/xml_xpath_runner.html

<!doctype html>
<title>XPath tests</title>
<script src='/resources/testharness.js'></script>
<script src='/resources/testharnessreport.js'></script>
<script>
setup({ explicit_done: true });

function find_child_element(context, element) {
  for (var i = 0; i < context.childNodes.length; i++) {
    var child = context.childNodes[i];
    if (child.nodeType === Node.ELEMENT_NODE && child.tagName === element)
      return child;
  }
}

function xpath_test(test_el) {
  /* note this func adopts the tree! */
  var new_doc = document.implementation.createDocument("", "");
  var xpath = find_child_element(test_el, "xpath");
  var tree = find_child_element(test_el, "tree");
  var actual_tree = new_doc.adoptNode(tree.firstElementChild);
  new_doc.appendChild(actual_tree);
  test(function() {
    var result = new_doc.evaluate(xpath.textContent, // expression
                                  actual_tree, // context node
                                  new_doc.createNSResolver(actual_tree), // resolver
                                  XPathResult.ANY_TYPE, // type
                                  null); // result
    var matched = [];
    var cur;
    while ((cur = result.iterateNext()) !== null) {
      matched.push(cur);
    }
    assert_equals(matched.length, 1, "Should match one node");
  });
}

var xhr = new XMLHttpRequest();
xhr.open("GET", "xml_xpath_tests.xml");
xhr.onload = function(e) {
  var tests = xhr.responseXML.documentElement;
  for (var i = 0; i < tests.childNodes.length; i++) {
    var child = tests.childNodes[i];
    if (child.nodeType === Node.ELEMENT_NODE) {
      xpath_test(child);
    }
  }
  done();
};
xhr.send();
</script>