containertiming-with-child-text.html

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<!DOCTYPE HTML>

<meta charset=utf-8>

<title>Container Timing: observe with a node with containertiming and a text child</title>

<body>

<style>

body {

  margin: 0;

</style>

<script src="/resources/testharness.js"></script>

<script src="/resources/testharnessreport.js"></script>

<script src="/container-timing/resources/container-timing-helpers.js"></script>

<script src="/element-timing/resources/element-timing-helpers.js"></script>

<script>

  let beforeRender;

  async_test(function (t) {

    assert_implements(window.PerformanceContainerTiming, "PerformanceContainerTiming is not implemented");

    const observer = new PerformanceObserver(

      t.step_func_done(function(entryList) {

        assert_equals(entryList.getEntries().length, 1);

        const entry = entryList.getEntries()[0];

        checkContainerEntry(entry, 'div_ct', 'p_id', beforeRender)

})

);

    observer.observe({entryTypes: ['container']});

    // Add the text during onload to be sure that the observer is registered

    // in time.

    window.onload = () => {

      // Add a div that is the container timing root

      const div = document.createElement('div');

      div.setAttribute('containertiming', 'div_ct');

      document.body.appendChild(div);

      const p = document.createElement('p');

      p.id = 'p_id';

      p.innerText = "This is a text";

      div.appendChild(p);

      beforeRender = performance.now();

};

  }, 'Paint of the text child of container timing is reported.');

</script>

</body>