intersection-observer/clip-path.html

<!DOCTYPE html>
<meta name="viewport" content="width=device-width,initial-scale=1">
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<script src="./resources/intersection-observer-test-utils.js"></script>

<style>
body { margin: 0 }
pre, #log {
  position: absolute;
  top: 0;
  left: 200px;
}
#target {
  background-color: green;
  width: 100px;
  height: 100px;
}
#container {
  padding: 8px;
  width: 0px;
  height: 0px;
}
</style>

<div id="container">
  <div id="target"></div>
</div>

<script>
var vw = document.documentElement.clientWidth;
var vh = document.documentElement.clientHeight;

var entries = [];

promise_test(async function(t) {
  var target = document.getElementById("target");
  var container = document.getElementById("container");
  var root = document.getElementById("root");
  var observer = new IntersectionObserver(function(changes) {
    entries = entries.concat(changes)
  });
  observer.observe(target);
  entries = entries.concat(observer.takeRecords());
  assert_equals(entries.length, 0, "No initial notifications.");

  await waitForNotification();

  checkLastEntry(
    entries,
    0,
    [8, 108, 8, 108, 8, 108, 8, 108, 0, vw, 0, vh, true],
  );
  container.style.clipPath = "inset(1000px)";

  await waitForNotification();

  checkLastEntry(
    entries,
    1,
    [8, 108, 8, 108, 0, 0, 0, 0, 0, vw, 0, vh, false],
  );

  container.style.clipPath = "";

  await waitForNotification();

  checkLastEntry(
    entries,
    2,
    [8, 108, 8, 108, 8, 108, 8, 108, 0, vw, 0, vh, true],
  );
});
</script>