chromium/third_party/blink/web_tests/external/wpt/web-animations/responsive/clip.html

<!DOCTYPE html>
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<div id='container'>
    <div id='element'></div>
</div>
<script>

var container = document.getElementById('container');
var element = document.getElementById('element');

test(function() {
    var keyframes = [
        {clip: 'inherit'},
        {clip: 'rect(10px, 20px, 30px, 40px)'}
    ];

    container.style.clip = 'rect(10px, 20px, 30px, 40px)';
    var player = element.animate(keyframes, 20);

    player.pause();
    player.currentTime = 5;
    assert_equals(getComputedStyle(element).clip, 'rect(10px, 20px, 30px, 40px)');

    container.style.clip = 'rect(10px, 20px, 430px, 440px)';
    assert_equals(getComputedStyle(element).clip, 'rect(10px, 20px, 330px, 340px)');
}, 'clip responsive to inherited clip changes');

test(function() {
    var keyframes = [
        {clip: 'inherit'},
        {clip: 'rect(10px, 20px, 30px, auto)'}
    ];

    container.style.clip = 'auto';
    var player = element.animate(keyframes, 20);

    player.pause();
    player.currentTime = 5;
    assert_equals(getComputedStyle(element).clip, 'auto');

    container.style.clip = 'rect(410px, 420px, 30px, auto)';
    assert_equals(getComputedStyle(element).clip, 'rect(310px, 320px, 30px, auto)');
}, 'clip responsive to inherited clip changes from auto');
</script>