quals(target.computedStyleMap().getAll(name).length, 3);
    assert_true(target.computedStyleMap().getAll(name).every(x => x instanceof CSSUnitValue));
}, 'All computed values correctly reified in space-separated list');

test(function(){
    let name = generate_property({syntax: '<length>#', initialValue: '10px, 20px'});
    assert_equals(target.computedStyleMap().getAll(name).length, 2);
    assert_true(target.computedStyleMap().getAll(name).every(x => x instanceof CSSUnitValue));

    target.style = `${n