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Test Info:
- This WPT test may be referenced by the following Test IDs:
- /quirks/supports.html - WPT Dashboard Interop Dashboard
<!--quirks-->
<title>Syntax quirks in @supports/CSS.supports</title>
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<style>
/* sanity check */
@supports (background-color: lime) { #a { background-color: lime } }
@supports (background-position: 1px 1px) { #a { background-position: 1px 1px } }
/* test */
@supports (background-color: 00ff00) { #b { background-color: 00ff00 } }
@supports (background-position: 1 1) { #b { background-position: 1 1 } }
</style>
<div id=a></div>
<div id=b></div>
<div id=c></div> <!-- c unstyled -->
<script>
var a = document.getElementById('a');
var b = document.getElementById('b');
var c = document.getElementById('c');
test(function() {
assert_not_equals(getComputedStyle(a).backgroundColor, getComputedStyle(c).backgroundColor);
}, 'Sanity check @supports color');
test(function() {
assert_equals(getComputedStyle(b).backgroundColor, getComputedStyle(a).backgroundColor);
}, '@supports quirky color');
test(function() {
assert_false(CSS.supports('background-color', '00ff00'));
}, 'CSS.supports() quirky color');
test(function() {
assert_not_equals(getComputedStyle(a).backgroundPosition, getComputedStyle(c).backgroundPosition);
}, 'Sanity check @supports length');
test(function() {
assert_equals(getComputedStyle(b).backgroundPosition, getComputedStyle(a).backgroundPosition);
}, '@supports quirky length');
test(function() {
assert_false(CSS.supports('background-position', '1 1'));
}, 'CSS.supports() quirky length');
</script>