code: function skipBulletListMarker(state, startLine) {
    var marker, pos, max, ch;
  
    pos = state.bMarks[startLine] + state.tShift[startLine];
    max = state.eMarks[startLine];
  
    marker = state.src.charCodeAt(pos++);
    // Check bullet
    if (marker !== 0x2A/* * */ &&
        marker !== 0x2D/* - */ &&
        marker !== 0x2B/* + */) {
      return -1;
    }
  
    if (pos < max) {
      ch = state.src.charCodeAt(pos);
  
      if (!isSpace(ch)) {
        // " -test " - is not a list item
        return -1;
      }
    }
  
    return pos;
  }
docs: Search `[-+*][\n ]`, returns next pos after marker on success or -1 on fail.