chromium/third_party/blink/web_tests/animations/interpolation/border-interpolation.html

<!DOCTYPE html>
<meta charset="UTF-8">
<style>
.target {
  width: 10px;
  height: 10px;
  background-color: black;
}
.expected {
  background-color: green;
}
</style>
<body>
<script src="resources/interpolation-test.js"></script>
<script>

assertInterpolation({
  property: 'border',
  from: '10px solid #000',
  to: '20px dashed #000',
  method: 'CSS Transitions',
}, [
  {at: -0.3, is: '7px dashed #000'},
  {at: 0, is: '10px dashed #000'},
  {at: 0.3, is: '13px dashed #000'},
  {at: 0.6, is: '16px dashed #000'},
  {at: 1, is: '20px dashed #000'},
  {at: 1.5, is: '25px dashed #000'},
]);

assertInterpolation({
  property: 'border',
  from: '10px solid #000',
  to: '20px dashed #000',
  method: 'CSS Animations',
}, [
  {at: -0.3, is: '7px solid #000'},
  {at: 0, is: '10px solid #000'},
  {at: 0.3, is: '13px solid #000'},
  {at: 0.6, is: '16px dashed #000'},
  {at: 1, is: '20px dashed #000'},
  {at: 1.5, is: '25px dashed #000'},
]);

assertInterpolation({
  property: 'border',
  from: '10px solid #000',
  to: '20px dashed #000',
  method: 'Web Animations',
}, [
  {at: -0.3, is: '7px solid #000'},
  {at: 0, is: '10px solid #000'},
  {at: 0.3, is: '13px solid #000'},
  {at: 0.6, is: '16px dashed #000'},
  {at: 1, is: '20px dashed #000'},
  {at: 1.5, is: '25px dashed #000'},
]);

</script>
</body>