: 'max-width',
  underlying: '10%',
  addFrom: '100px',
  addTo: '20%',
}, [
  {at: -0.3, expect: 'calc(130px + 4%)'},
  {at: 0, expect: 'calc(100px + 10%)'},
  {at: 0.5, expect: 'calc(50px + 20%)'},
  {at: 1, expect: '30%'},
  {at: 1.5, expect: 'calc(-50px + 40%)'},
]);

test_composition({
  property: 'max-width',
  underlying: '50px',
  addFrom: '100px',
  replaceTo: '200px',
}, [
  {at: -0.3, expect: '135px'},
  {at: 0, expect: '150px'},
  {at: 0.5, expect: '175px'},
  {at: 1, expect: '200px'},
  {at: 1.