css/cssom/CSSContainerRule.tentative.html

<!doctype html>
<meta charset="utf-8">
<title>CSSContainerRule</title>
<link rel="author" title="Emilio Cobos Álvarez" href="mailto:emilio@crisal.io">
<link rel="author" title="Mozilla" href="https://mozilla.org">
<link rel="help" href="https://drafts.csswg.org/css-contain-3/#the-csscontainerrule-interface">
<script src=/resources/testharness.js></script>
<script src=/resources/testharnessreport.js></script>
<style id="sheet"></style>
<script>
  const kTests = [
    {
      rule: "@container name (min-width: 100px) {}",
      name: "name",
      query: "(min-width: 100px)",
    },
    {
      rule: "@container (min-width: 100px) {}",
      name: "",
      query: "(min-width: 100px)",
    },
  ];

  const sheet = document.getElementById("sheet").sheet;
  for (let { rule, name, query } of kTests) {
    test(function() {
      sheet.insertRule(rule, 0);
      let r = sheet.cssRules[0];
      assert_true(r instanceof CSSContainerRule);
      assert_equals(r.containerName, name, "containerName");
      assert_equals(r.containerQuery, query, "containerQuery");
      assert_equals(r.conditionText, name ? `${name} ${query}` : query, "conditionText");
    }, rule)
  }
</script>