on () {
  assert_equals(getComputedValueFor('valid_digits_calc_1_plus_1'), 'digits 2');
}, 'Computed value for `text-combine-upright: digits calc(1 + 1)` is `digits 2`');

test(function () {
  assert_equals(getComputedValueFor('valid_digits_calc_1_plus_1_plus_1'), 'digits 3');
}, 'Computed value for `text-combine-upright: digits calc(1 + 1 + 1)` is `digits 3`');

test(function () {
  assert_equals(getComputedValueFor('valid_digits_calc_2_plus_2'), 'digits 4');
}, 'Computed value for `text-combine-upright: d