 be thrown.")

// Step 3
test(function() {
  var el = document.createElement("foo")
  el.setAttributeNS(null, "aa", "bb")
  el.setAttributeNS("", "xx", "bb")
  attributes_are(el, [["aa", "bb"],
                      ["xx", "bb"]])
}, "null and the empty string should result in a null namespace.")

// Step 4
test(function() {
  var el = document.createElement("foo")
  assert_throws_dom("NAMESPACE_ERR",
                    function() { el.setAttributeNS("", "aa:bb", "fail") })
  assert_throws_dom("NAMESPACE_E