docs: private void push(ScopeOptions options) throws JSONException {
          m_top += 1;
          if (m_top >= MAX_DEPTH) {
              throw new JSONException("Nesting too deep.");
          }
          try {
              m_writer.write(options.m_prefix);
          }
          catch (IOException e) {
              throw new JSONException(e);
          }
  
          HashSetOfString keyTracker = options.createKeyTracker();
          m_scopeStack[m_top] = keyTracker;
          m_mode = (keyTracker == null) ? 'a' : 'k';
          m_expectingComma = false;
      }