<!DOCTYPE html>
<link rel="help" href="https://compat.spec.whatwg.org/#css-gradients-webkit-radial-gradient">
<link rel="help" href="https://www.w3.org/TR/css3-images/#radial-gradients">
<meta name="assert" content="Negative radii values are invalid.">
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<script>
test(function() {
    assert_true(CSS.supports("background-image", "-webkit-radial-gradient(1px 2px, 3% 4%, red, blue)"));
}, '-webkit-radial-gradient accepts comma before color stops.');

test(function() {
    assert_false(CSS.supports("background-image", "-webkit-radial-gradient(1px 2px, 3% 4% red, blue)"));
}, '-webkit-radial-gradient rejects missing comma before color stops.');
</script>