HasSiblingDescendantInvalidationAllSubjects.html

<!DOCTYPE html>
<html>
<head>
<script src="../resources/runner.js"></script>
<style>
  div { color: grey }
  .a:has(~ .b .c) { color: green }
</style>
</head>
<body>
<div id=container></div></div>
<script>

function makeTree(element, depth, children) {
  if (depth <= 0) {
    var child = document.createElement("div");
    child.id = 'sibling_descendant';
    element.appendChild(child);
    return;
  }

  for (var i = 0; i < children - 1; i++) {
    var child = document.createElement("div");
    child.classList.add("a");
    child.id = 'subject_' + depth + '_' + i;
    element.appendChild(child);
  }
  var child = document.createElement("div");
  child.classList.add("b");
  element.appendChild(child);
  makeTree(child, depth - 1, children);
}

makeTree(container, 10, 10);
container.offsetHeight; // force recalc style

var runFunction = function()
{
  sibling_descendant.classList.toggle("c");
  container.offsetHeight; // force recalc style
  sibling_descendant.classList.toggle("c");
  container.offsetHeight; // force recalc style
}

PerfTestRunner.measureRunsPerSecond({
  description: "Measures performance of the '.a:has(~ .b .c)' invalidation with all subject elements.",
  run: runFunction
});

</script>
</body>
</html>

chromium/third_party/blink/perf_tests/css/HasSiblingDescendantInvalidationAllSubjects.html