chromium/third_party/blink/web_tests/animations/interpolation/webkit-mask-box-image-width-interpolation.html

<!DOCTYPE html>
<meta charset="UTF-8">
<style>
.parent {
  -webkit-mask-box-image-width: 30px;
}
.target {
  width: 100px;
  height: 100px;
  background-color: black;
  display: inline-block;
  -webkit-mask-box-image-source: linear-gradient(45deg, rgba(0, 0, 0, 0), rgba(0, 0, 0, 1));
  -webkit-mask-box-image-width: 10px;
}
.expected {
  background-color: green;
  margin-right: 2px;
}
</style>
<body>
<script src="resources/interpolation-test.js"></script>
<script>
assertInterpolation({
  property: '-webkit-mask-box-image-width',
  from: neutralKeyframe,
  to: '20px',
}, [
  {at: -0.3, is: '7px'},
  {at: 0, is: '10px'},
  {at: 0.3, is: '13px'},
  {at: 0.6, is: '16px'},
  {at: 1, is: '20px'},
  {at: 1.5, is: '25px'},
  {at: 5, is: '60px'},
  {at: 10, is: '110px'},
]);

assertNoInterpolation({
  property: '-webkit-mask-box-image-width',
  from: 'initial',
  to: '20px',
});

assertInterpolation({
  property: '-webkit-mask-box-image-width',
  from: 'inherit',
  to: '20px',
}, [
  {at: -0.3, is: '33px'},
  {at: 0, is: '30px'},
  {at: 0.3, is: '27px'},
  {at: 0.6, is: '24px'},
  {at: 1, is: '20px'},
  {at: 1.5, is: '15px'},
  {at: 5, is: '0px'},
  {at: 10, is: '0px'},
]);

assertNoInterpolation({
  property: '-webkit-mask-box-image-width',
  from: 'unset',
  to: '20px',
});

assertInterpolation({
  property: '-webkit-mask-box-image-width',
  from: '0px',
  to: '20px'
}, [
  {at: -0.3, is: '0px'}, // CSS -webkit-mask-box-image-width can't be negative.
  {at: 0, is: '0px'},
  {at: 0.3, is: '6px'},
  {at: 0.6, is: '12px'},
  {at: 1, is: '20px'},
  {at: 1.5, is: '30px'},
  {at: 5, is: '100px'},
  {at: 10, is: '200px'}
]);
assertInterpolation({
  property: '-webkit-mask-box-image-width',
  from: '0',
  to: '20'
}, [
  {at: -0.3, is: '0'}, // CSS -webkit-mask-box-image-width can't be negative.
  {at: 0, is: '0'},
  {at: 0.3, is: '6'},
  {at: 0.6, is: '12'},
  {at: 1, is: '20'},
  {at: 1.5, is: '30'},
  {at: 5, is: '100'},
  {at: 10, is: '200'}
]);
</script>
</body>