token-stream-type-interpolation.html

<!DOCTYPE html>
<meta charset="UTF-8">
<style>
.parent {
  --token-stream: parent tokens;
}
.target {
  --token-stream: underlying tokens;
}
</style>
<body>
<script src="../interpolation/resources/interpolation-test.js"></script>
<script>
CSS.registerProperty({
  name: '--token-stream',
  syntax: '*',
  initialValue: 'initial tokens',
  inherits: false,
});

assertNoInterpolation({
  property: '--token-stream',
  from: neutralKeyframe,
  to: 'value tokens',
});

assertNoInterpolation({
  property: '--token-stream',
  from: 'initial',
  to: 'value tokens',
});

assertNoInterpolation({
  property: '--token-stream',
  from: 'inherit',
  to: 'value tokens',
});

assertNoInterpolation({
  property: '--token-stream',
  from: 'unset',
  to: 'value tokens',
});

assertNoInterpolation({
  property: '--token-stream',
  from: 'a b c d',
  to: 'e f g h',
});
</script>
</body>

chromium/third_party/blink/web_tests/animations/custom-properties/token-stream-type-interpolation.html