<!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>
<script src="./resources/utils.js"></script>
<div id=target></div>
<script>

function test_initial_value(reg, expected) {
    let suffix = reg.inherits === true ? ', inherits' : '';
    test(function(){
        let name = generate_property(reg);
        let actual = getComputedStyle(target).getPropertyValue(name);
        assert_equals(actual, expected);
    }, `Initial value for ${reg.syntax} correctly computed [${reg.initialValue}${suffix}]`);
}

test_initial_value({ syntax: '<length>', initialValue: 'calc(10px + 15px)' }, '25px');
test_initial_value({ syntax: '<length-percentage>', initialValue: 'calc(1in + 10% + 4px)' }, 'calc(10% + 100px)');
test_initial_value({ syntax: '<color>', initialValue: 'pink', inherits: true }, 'rgb(255, 192, 203)');
test_initial_value({ syntax: '<color>', initialValue: 'purple' }, 'rgb(128, 0, 128)');
test_initial_value({ syntax: '<transform-function>', initialValue: 'rotate(42deg)' }, 'rotate(42deg)');
test_initial_value({ syntax: '<transform-list>', initialValue: 'scale(calc(2 + 2))' }, 'scale(4)');
test_initial_value({ syntax: '<transform-list>', initialValue: 'scale(calc(2 + 1)) translateX(calc(3px + 1px))' }, 'scale(3) translateX(4px)');

// Test that the initial value of the custom property 'reg' is successfully
// substituted into 'property'.
function test_substituted_value(reg, property, expected) {
    let inherits_text = reg.inherits === true ? 'inherited' : 'non-inherited';
    test(function(){
        try {
            let name = generate_property(reg);
            target.style = `${property}:var(${name});`;
            assert_equals(getComputedStyle(target).getPropertyValue(property), expected);
        } finally {
            target.style = '';
        }
    }, `Initial ${inherits_text} value can be substituted [${reg.initialValue}, ${property}]`);
}

test_substituted_value({ syntax: '<color>', initialValue: 'purple', inherits: true }, 'color', 'rgb(128, 0, 128)');
test_substituted_value({ syntax: '<color>', initialValue: 'pink' }, 'background-color', 'rgb(255, 192, 203)');

</script>