client-hints/sec-ch-ua.https.html

<!DOCTYPE html>
<head>
<script src=/resources/testharness.js></script>
<script src=/resources/testharnessreport.js></script>
<script>
  var sec_ch_ua_header = "";

  function grabSECCHUAHeader(t) {
    return new Promise((resolve, reject) => {
      var w;
      window.onmessage = e => {
        try {
          resolve(e.data.header)
        } catch (ex) {
          reject(ex);
        }
      };
      w = window.open("./resources/sec-ch-ua.py");
      t.add_cleanup(w.close);
    });
  }
  promise_test(t => {
    return grabSECCHUAHeader(t).then(header => {
      sec_ch_ua_header = header;
      assert_not_equals(sec_ch_ua_header, "", "`Sec-CH-UA` is sent.");
    });
  }, "Open HTTPS window: `Sec-CH-UA` header returned by default.");

  promise_test(t => {
    return grabSECCHUAHeader(t).then(header => {
      assert_not_equals(header, "", "The `Sec-CH-UA` header is delivered.");
      assert_equals(header, sec_ch_ua_header,
        "The `Sec-CH-UA` header did not change between requests.");
    });
  }, "Open HTTPS window: `Sec-CH-UA` header is consistent across versions.");

  promise_test(t => {
    return grabSECCHUAHeader(t).then(header => {
      assert_true(header.split(", ").every((brand) => {
        let brandEnd = brand.indexOf(";v=");
        assert_true(brandEnd !== -1,
          "A well-formed Sec-CH-UA header must have version (v=) params");
        /* 32 + 2, becuase of the extra quotes padding the brand,
           e.g. '"lol";v=22"' */
        return brandEnd < 34;
      }));
    });
  }, "Open HTTPS window: No brand in `Sec-CH-UA` header is > than 32 chars.");
</script>
</head>