code: @SuppressWarnings("squid:S1067")
      protected Token fetchSymbol() {
          Token result = Token.create(Token.TokenType.SYMBOL, input.current());
          result.addToTrigger(input.consume());
          if (result.isSymbol("*") && input.current().is('*')
              || result.isSymbol("&") && input.current().is('&')
              || result.isSymbol("|") && input.current().is('|')
              || result.isSymbol() && input.current().is('=')) {
              result.addToTrigger(input.consume());
          }
          return result;
      }
docs: Reads and returns a symbol.
  <p>
  A symbol are one or two characters, which don't match any other token type. In most cases, this will be
  operators like + or *.
  
  @return the parsed symbol as Token