chromium/third_party/blink/web_tests/external/wpt/xhr/headers-normalize-response.htm

<!DOCTYPE html>
<meta charset=utf-8>
<title>Whitespace and null in header values</title>
<script src=/resources/testharness.js></script>
<script src=/resources/testharnessreport.js></script>
<div id=log></div>
<script>
function error(val) {
  test(() => {
    const client = new XMLHttpRequest();
    client.open("GET", "resources/parse-headers.py?my-custom-header="+encodeURIComponent(val), false);
    assert_throws_dom("NetworkError", () => client.send());
  }, "Header value: " + val.replace("\0", "\\0"));
}

function matchHeaderValue(val) {
    test(function () {
        var client = new XMLHttpRequest();
        var trimmed = val.trim();
        client.open("GET", "resources/parse-headers.py?my-custom-header="+encodeURIComponent(val), false);
        client.send();
        var r = client.getResponseHeader("My-Custom-Header");

        assert_equals(r, trimmed);
    }, "Header value: " + val.replace(/\t/g, "[tab]").replace(/ /g, "_"));
}

error("hello world\0");
error("\0hello world");
error("hello\0world");
matchHeaderValue("  hello world");
matchHeaderValue("hello world  ");
matchHeaderValue("  hello world  ");
matchHeaderValue("\thello world");
matchHeaderValue("hello world\t");
matchHeaderValue("\thello world\t");
matchHeaderValue("hello      world");
matchHeaderValue("hello\tworld");
error("\0");
matchHeaderValue("   ");
matchHeaderValue("\t");
matchHeaderValue("");
</script>