<!doctype html>
<script src="../resources/testharness.js"></script>
<script src="../resources/testharnessreport.js"></script>
<style>
#container {
  overflow: auto;
  border: 1px solid black;
  width: 200px;
  height: 100px;
}
#target {
  width: 300px;
  height: 200px;
  position: relative;
  top: -50px;
  left: -40px;
  background-color: rgba(0, 255, 0, 0.3);
}
</style>
<p>Overflow, with position:relative. position:relative affects overflow.</p>
<div id="container">
  <div id="target"></div>
</div>
<script>

var container = document.querySelector('#container');
var target = document.querySelector('#target');

test(function() {
  var targetStyle = window.getComputedStyle(target);
  assert_equals(container.scrollWidth,
    target.offsetWidth + parseInt(targetStyle.left),
    "width");
  assert_equals(container.scrollHeight,
    target.offsetHeight + parseInt(targetStyle.top),
    "height");
}, "relative overflow");

test(function() {
  target.style.top = "-66px";
  var targetStyle = window.getComputedStyle(target);
  assert_equals(container.scrollWidth,
    target.offsetWidth + parseInt(targetStyle.left),
    "width");
  assert_equals(container.scrollHeight,
    target.offsetHeight + parseInt(targetStyle.top),
    "height");
}, "relative overflow, after target move");
</script>