x'},
  {at: 0.6, expect: '6.4px'},
  {at: 1, expect: '0px'},
]);

test_interpolation({
  property: 'text-decoration-thickness',
  from: '16px',
  to: '2em',
}, [
  {at: 0, expect: '16px'},
  {at: 0.3, expect: '20.8px'},
  {at: 0.6, expect: '25.6px'},
  {at: 1, expect: '32px'},
]);

test_interpolation({
  property: 'text-decoration-thickness',
  from: '16px',
  to: '0%',
}, [
  {at: 0, expect: 'calc(0% + 16px)'},
  {at: 0.3, expect: 'calc(0% + 11.2px)'},
  {at: 0.6, expect: 'calc(0% + 6.4px)'},
  {at: 1, exp