2, 143, 0) 16px 24px 16px'},
  {at: 1, expect: 'rgb(0, 128, 0) 20px 20px 20px'},
  {at: 1.5, expect: 'rgb(0, 110, 0) 25px 15px 25px'},
]);

test_interpolation({
  property: 'text-shadow',
  from: 'initial',
  to: 'green 20px 20px 20px',
}, [
  {at: -0.3, expect: 'rgba(0, 0, 0, 0) -6px -6px 0px'},
  {at: 0, expect: 'rgba(0, 0, 0, 0) 0px 0px 0px'},
  {at: 0.3, expect: 'rgba(0, 128, 0, 0.3) 6px 6px 6px'},
  {at: 0.6, expect: 'rgba(0, 128, 0, 0.6) 12px 12px 12px'},
  {at: 1, expect: 'rgb(0, 128, 0) 20px 20px 20