css/css-pseudo/parsing/highlight-pseudos.html

<!doctype html>
<meta charset="utf-8">
<title>CSS Pseudo-Elements Test: highlight selectors parsing</title>
<link rel="help" href="https://drafts.csswg.org/css-pseudo/#highlight-selectors">
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<script src="/css/support/parsing-testcommon.js"></script>
<script>
  for (const pseudo of ["::selection", "::target-text", "::spelling-error", "::grammar-error"]) {
    test_valid_selector(`${pseudo}`);
    test_valid_selector(`.a${pseudo}`);
    test_valid_selector(`div ${pseudo}`);
    test_valid_selector(`::part(my-part)${pseudo}`);

    test_invalid_selector(`::before${pseudo}`);
    test_invalid_selector(`${pseudo}.a`);
    test_invalid_selector(`${pseudo} div`);
    test_invalid_selector(`${pseudo}::after`);
    test_invalid_selector(`${pseudo}:hover`);
    test_invalid_selector(`:not(${pseudo})`);
  }
</script>