final Map<String, Object> sourceMap = new HashMap<>();
        if (name != null) {
            sourceMap.put("name", name);
        }
        if (password != null) {
            sourceMap.put("password", password);
        }
        if (groups != null) {
            sourceMap.put("groups", groups);
        }
        if (roles != null) {
            sourceMap.put("roles", roles);
        }

        DocMap docMap = new DocMap(parentMap);

        Map<String, Object> sourceMap = new HashMap<>();
        sourceMap.put("key1", "value1");
        sourceMap.put("key2", "value2");
        sourceMap.put("key3", "value3");

        docMap.putAll(sourceMap);

        assertEquals(3, docMap.size());
        assertEquals("value1", docMap.get("key1"));

    ImmutableBiMap<String, String> specialCases =
        ImmutableBiMap.<String, String>builder()
            .put("CDN_LOOP", "CDN-Loop")
            .put("ETAG", "ETag")
            .put("SOURCE_MAP", "SourceMap")
            .put("SEC_CH_UA_WOW64", "Sec-CH-UA-WoW64")
            .put("SEC_WEBSOCKET_ACCEPT", "Sec-WebSocket-Accept")
            .put("SEC_WEBSOCKET_EXTENSIONS", "Sec-WebSocket-Extensions")

  public static final String SET_COOKIE2 = "Set-Cookie2";

  /**
   * The HTTP <a href="https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/SourceMap">{@code
   * SourceMap}</a> header field name.
   *
   * @since 27.1
   */
  public static final String SOURCE_MAP = "SourceMap";

  /**
   * The HTTP <a href="https://github.com/WICG/nav-speculation/blob/main/opt-in.md">{@code

     *
     * @param sourceMap The source map containing the date field.
     * @param name The name of the date field.
     * @return The Date object, or null if the field doesn't contain a valid date.
     */
    protected Date getDateFromSource(final Map<String, Object> sourceMap, final String name) {
        final Object obj = sourceMap.get(name);
        if (obj instanceof Date) {