LayoutTests/highlight/highlight-node-inserted-inside-range.html

<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>CSS Custom Highlight API: a node inserted inside a highlight range after it has been painted is highlighted</title>
<style>
#target {
    font: 16px/20px monospace;
    white-space: pre;
    width: max-content;
    color: black;
}
#target::highlight(test),
#inner::highlight(test) {
    background-color: lime;
}
</style>
<script src="../resources/ui-helper.js"></script>
</head>
<body>
<p>PASS if the bar below is one solid lime rectangle with no gap in the middle.</p>
<div id="target">AAAA<span id="inner"></span>AAAA</div>
<script>
if (window.testRunner)
    testRunner.waitUntilDone();

(async () => {
    // Unlike a live Range, a StaticRange is not told about the insertion below, so nothing about the range
    // itself changes when the node is inserted.
    const target = document.getElementById("target");
    CSS.highlights.set("test", new Highlight(new StaticRange({
        startContainer: target.firstChild,
        startOffset: 0,
        endContainer: target.lastChild,
        endOffset: 4,
    })));

    await UIHelper.renderingUpdate();

    document.getElementById("inner").textContent = "AAAA";

    if (window.testRunner)
        testRunner.notifyDone();
})();
</script>
</body>
</html>