n({
  property: 'transform',
  underlying: 'rotateX(20deg)',
  addFrom: 'rotateX(40deg)',
  addTo: 'rotateX(60deg)',
}, [
  {at: -0.5, expect: 'rotateX(50deg)'},
  {at: 0, expect: 'rotateX(60deg)'},
  {at: 0.25, expect: 'rotateX(65deg)'},
  {at: 0.5, expect: 'rotateX(70deg)'},
  {at: 0.75, expect: 'rotateX(75deg)'},
  {at: 1, expect: 'rotateX(80deg)'},
  {at: 1.5, expect: 'rotateX(90deg)'},
]);

test_composition({
  property: 'transform',
  underlying: 'rotateY(20deg)',
  addFrom: 'rotateY(40deg)',
  addTo: