docs: @Nonnull
      public static String escapeMetricNamePart(@Nonnull String namePart) {
          int i = 0;
          int l = namePart.length();
          while (i < l) {
              char ch = namePart.charAt(i);
              if (ch == ',' || ch == '=' || ch == '\\') {
                  break;
              }
              i++;
          }
          if (i == l) {
              return namePart;
          }
          StringBuilder sb = new StringBuilder(namePart.length() + 3);
          sb.append(namePart, 0, i);
          while (i < l) {
              char ch = namePart.charAt(i++);
              if (ch == ',' || ch == '=' || ch == '\\') {
                  sb.append('\\');
              }
              sb.append(ch);
          }
          return sb.toString();
      }