chromium/third_party/blink/web_tests/external/wpt/css/css-sizing/aspect-ratio/box-sizing-dimensions.html

<!DOCTYPE html>
<meta charset="utf-8">
<title>CSS aspect-ratio: uses content box when "auto" is present and box-sizing dimensions when it is absent</title>
<link rel="help" href="https://drafts.csswg.org/css-sizing-4/#aspect-ratio">
<meta name="assert" content='CSS aspect-ratio: uses content box when "auto" is present and box-sizing dimensions when it is absent.'>
<style>
img {
    border: 20px solid blue;
    width: 100px;
    height: auto;
}

.aspect {
    aspect-ratio: 2 / 1;
}

.aspect-auto {
    aspect-ratio: auto 2 / 1;
}

.border-box {
    box-sizing: border-box;
}

.non-replaced {
    background: green;
    border: 20px solid blue;
    width: 100px;
}
</style>
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<script src="/resources/check-layout-th.js"></script>

<body onload="checkLayout('.item')">

<img class="item aspect" src="./support/20x50-green.png" width="20" height="50" data-expected-width="140" data-expected-height="90">

<img class="item aspect border-box" src="./support/20x50-green.png" width="20" height="50" data-expected-width="100" data-expected-height="50">

<img class="item aspect-auto" src="./support/20x50-green.png" width="20" height="50" data-expected-width="140" data-expected-height="290">

<img class="item aspect-auto border-box" src="./support/20x50-green.png" width="20" height="50" data-expected-width="100" data-expected-height="190">

<div class="item non-replaced aspect" data-expected-width="140" data-expected-height="90"></div>

<div class="item non-replaced aspect border-box" data-expected-width="100" data-expected-height="50"></div>

<div class="item non-replaced aspect-auto" data-expected-width="140" data-expected-height="90"></div>

<div class="item non-replaced aspect-auto border-box" data-expected-width="100" data-expected-height="70"></div>