Blitz - WPT: mask-shorthand-subproperties-reset.html

wpt / css / css-masking / mask-shorthand-subproperties-reset.html

Data from commit:
a50cb89 wpt: run reference-named files which are themselves tests (#836) (2026-09-03)

Subtest	Status	Message
Property mask-composite should be reset to its initial value.	PASS
Property mask-image should be reset to its initial value.	PASS
Property mask-mode should be reset to its initial value.	PASS
Property mask-origin should be reset to its initial value.	PASS
Property mask-position should be reset to its initial value.	PASS
Property mask-repeat should be reset to its initial value.	PASS
Property mask-size should be reset to its initial value.	PASS

Enable JavaScript in test iframe

/css/css-masking/mask-shorthand-subproperties-reset.html

<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>Resetting mask shorthand subproperties</title>
<link rel="author" title="Tim Nguyen" href="https://github.com/nt1m">
<link rel="help" href="https://drafts.fxtf.org/css-masking/#the-mask">
<meta name="assert" content="All subproperties of the masking property are first reset to their initial values.">
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
</head>
<body>
<div id="test"></div>
<script>

function set_subproperty(property, value) {
  const element = document.getElementById('test')
  element.style = ''
  element.style[property] = value
}

function test_shorthand_resetting_subproperty(property, newValue) {
  if (!CSS.supports(property, newValue))
    return
  test(() => {
    let testElem = document.getElementById('test');
    let computed = window.getComputedStyle(testElem);
    let initialValue = computed[property];
    set_subproperty(property, newValue);
    document.getElementById('test').style.mask = 'url("#mask")';
    assert_equals(computed[property], initialValue);
    assert_not_equals(computed.mask, "");
  }, 'Property ' + property + ' should be reset to its initial value.')
}

test_shorthand_resetting_subproperty('mask-border-mode', 'luminance');
test_shorthand_resetting_subproperty('mask-border-outset', '10px 20px 30px 40px');
test_shorthand_resetting_subproperty('mask-border-repeat', 'round space');
test_shorthand_resetting_subproperty('mask-border-slice', '1 2 3 4 fill');
test_shorthand_resetting_subproperty('mask-border-source', 'url("#mask-border")');
test_shorthand_resetting_subproperty('mask-border-width', '10px 20px 30px 40px');
test_shorthand_resetting_subproperty('mask-clip', 'no-clip')
test_shorthand_resetting_subproperty('mask-composite', 'subtract')
test_shorthand_resetting_subproperty('mask-image', 'url("#mask-image")')
test_shorthand_resetting_subproperty('mask-mode', 'luminance')
test_shorthand_resetting_subproperty('mask-origin', 'content-box')
test_shorthand_resetting_subproperty('mask-position', '10px 10px')
test_shorthand_resetting_subproperty('mask-repeat', 'no-repeat')
test_shorthand_resetting_subproperty('mask-size', '10px')
</script>
</body>
</html>