chromium/third_party/blink/web_tests/external/wpt/css/css-sizing/contain-intrinsic-size/auto-010.html

<!DOCTYPE html>
<meta charset="utf-8">
<title>Last remembered size</title>
<link rel="author" title="Oriol Brufau" href="mailto:[email protected]">
<link rel="help" href="https://drafts.csswg.org/css-sizing-4/#last-remembered">
<link rel="help" href="https://drafts.csswg.org/css-sizing-4/#intrinsic-size-override">
<link rel="help" href="https://drafts.csswg.org/css-contain-2/#content-visibility">
<link rel="help" href="https://drafts.csswg.org/css-multicol-1/">
<link rel="help" href="https://github.com/w3c/csswg-drafts/issues/7598">
<meta name="assert" content="Tests that the last remembered size takes all fragments into account." />

<style>
#wrapper {
  column-width: 100px;
  width: max-content;
  height: 100px;
}
#target {
  width: max-content;
  height: max-content;
  background: orange;
}
#target::before {
  content: "";
  display: block;
}
.content-50-150::before {
  width: 50px;
  height: 150px;
}
.content-50-175::before {
  width: 50px;
  height: 175px;
}
.content-skip {
  content-visibility: hidden;
}
.cis-auto {
  contain-intrinsic-size: auto 1px;
}
</style>

<div id="log"></div>

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

<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<script>
const target = document.getElementById("target");

function checkSizes(expectedSizes, msg) {
  const rects = target.getClientRects();
  assert_equals(rects.length, expectedSizes.length, msg + " - fragments");
  for (let i = 0; i < rects.length; ++i) {
    assert_equals(rects[i].width, expectedSizes[i][0], `${msg} - fragment #${i+1} width`);
    assert_equals(rects[i].height, expectedSizes[i][1], `${msg} - fragment #${i+1} height`);
  }
}

function checkSize(expectedWidth, expectedHeight, msg) {
  assert_equals(target.clientWidth, expectedWidth, msg + " - clientWidth");
  assert_equals(target.clientHeight, expectedHeight, msg + " - clientHeight");
}

function nextRendering() {
  return new Promise(resolve => {
    requestAnimationFrame(() => requestAnimationFrame(() => resolve()));
  });
}

promise_test(async function() {
  target.className = "cis-auto content-50-150";
  checkSizes([[50, 100], [50, 50]], "Sizing normally");

  await nextRendering();
  target.className = "cis-auto content-skip";
  checkSize(50, 150, "Using last remembered size");
}, "Last remembered size supports multiple fragments");

promise_test(async function() {
  target.className = "cis-auto content-50-150";
  checkSizes([[50, 100], [50, 50]], "Sizing normally");

  await nextRendering();
  target.className = "cis-auto content-50-175";
  checkSizes([[50, 100], [50, 75]], "Sizing normally with new size");

  await nextRendering();
  target.className = "cis-auto content-skip";
  checkSize(50, 175, "Using updated last remembered size");
}, "Last remembered size is updated when 2nd fragment changes size");
</script>