registered-property-initial.html
<!DOCTYPE HTML>
<link rel="help" href="https://drafts.css-houdini.org/css-properties-values-api/#dom-propertydescriptor-initialvalue" />
<link rel="help" href="https://drafts.css-houdini.org/css-properties-values-api/#register-a-custom-property" />
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<style>
#target {
background: var(--inherited-color);
color: var(--non-inherited-color);
}
</style>
<div id=target></div>
<script>
CSS.registerProperty({name: '--length', syntax: '<length>', initialValue: 'calc(10px + 15px)'});
CSS.registerProperty({name: '--length-percentage', syntax: '<length-percentage>', initialValue: 'calc(1in + 10% + 4px)'});
CSS.registerProperty({name: '--inherited-color', syntax: '<color>', initialValue: 'pink', inherits: true});
CSS.registerProperty({name: '--non-inherited-color', syntax: '<color>', initialValue: 'purple'});
CSS.registerProperty({name: '--single-transform-list', syntax: '<transform-list>', initialValue: 'scale(calc(2 + 2))'});
CSS.registerProperty({name: '--multiple-transform-list', syntax: '<transform-list>', initialValue: 'scale(calc(2 + 1)) translateX(calc(3px + 1px))'});
test(function() {
computedStyle = getComputedStyle(target);
assert_equals(computedStyle.getPropertyValue('--length'), '25px');
assert_equals(computedStyle.getPropertyValue('--length-percentage'), 'calc(100px + 10%)');
assert_equals(computedStyle.getPropertyValue('--inherited-color'), 'pink');
assert_equals(computedStyle.getPropertyValue('--non-inherited-color'), 'purple');
assert_equals(computedStyle.getPropertyValue('--single-transform-list'), 'scale(4)');
assert_equals(computedStyle.getPropertyValue('--multiple-transform-list'), 'scale(3) translateX(4px)');
assert_equals(computedStyle.backgroundColor, 'rgb(255, 192, 203)');
assert_equals(computedStyle.color, 'rgb(128, 0, 128)');
}, "Initial values of registered properties can be referenced when no custom properties are explicitly set.");
</script>