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Test Info:
- This WPT test may be referenced by the following Test IDs:
- /css/css-animations/missing-values-first-keyframe.html - WPT Dashboard Interop Dashboard
<!DOCTYPE html>
<html>
<title>Missing properties in first keyframe</title>
<meta name="viewport" content="width=device-width,initial-scale=1,minimum-scale=1">
<link rel="help" href="https://www.w3.org/TR/web-animations-1/#the-effect-value-of-a-keyframe-animation-effect">
<meta name="assert"
content="CSS animation correctly interpolates from neutral keyframe">
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<script src="/web-animations/testcommon.js"></script>
<style type="text/css" media="screen">
body {
margin: 0;
}
.box {
position: relative;
width: 100px;
height: 100px;
left: 0;
background-color: green;
}
#box1 {
left: 200px;
animation: move-left 2s paused linear;
}
#box2 {
transform: translateX(200px);
animation: move-transform 2s paused linear;
}
@keyframes move-left {
0% {
opacity: 1;
}
25% {
opacity: 1;
}
50% {
left: 0;
opacity: 1;
}
100% {
left: 0;
opacity: 0;
}
}
@keyframes move-transform {
0% {
opacity: 1;
}
25% {
opacity: 1;
}
50% {
transform: translateX(0);
opacity: 1;
}
100% {
transform: translateX(0);
opacity: 0;
}
}
</style>
<body>
<div class="box" id="box1"></div>
<div class="box" id="box2"></div>
</body>
<script>
promise_test(async t => {
document.getAnimations().forEach(anim => {
anim.currentTime = 500;
});
assert_equals(getComputedStyle(box1).left, "100px");
assert_matrix_equals(
getComputedStyle(box2).transform,
'matrix(1, 0, 0, 1, 100, 0)');
}, 'Missing property values in the first keyframe are correctly ' +
'interpolated from a neutral keyframe value');
</script>
</html>