: 0.3, expect: 'calc(70% + 9.6px)'},
  {at: 0.6, expect: 'calc(40% + 19.2px)'},
  {at: 1, expect: 'calc(0% + 32px)'},
]);

test_interpolation({
  property: 'text-decoration-thickness',
  from: '100%',
  to: '0em',
}, [
  {at: 0, expect: '100%'},
  {at: 0.3, expect: '70%'},
  {at: 0.6, expect: '40%'},
  {at: 1, expect: '0%'},
]);

test_interpolation({
  property: 'text-decoration-thickness',
  from: '100%',
  to: '2em',
}, [
  {at: 0, expect: '100%'},
  {at: 0.3, expect: 'calc(70% + 9.6px)'},
  {at: 0.6, exp