parse method

@override Node? parse(BlockParser parser)

Implementation

@override
Node? parse(BlockParser parser) {
  final childLines = <String>[parser.current.content];
  final preserveSpace = parser.document.preserveSpace;
  if (preserveSpace) {
    //Look backward to merge empty lines in front of it
    var n = 0,
      diffSyntaxFound = false;
    while (parser.pos > 0) {
      --n;
      parser.retreat();
      if (!const EmptyBlockSyntax().canParse(parser)) {
        diffSyntaxFound = true;
        break;
      }

      childLines.insert(0, parser.current.content);
    }
    if (n < 0) {
      //If not retreat to a diff syntax, remove the separator, i.e.,
      //ingore one empty line
      if (diffSyntaxFound && childLines.length > 1) {
        childLines.removeAt(0); //remove the separator
      }

      parser.retreatBy(n); //restore pos
    }
  }

  parser.advance();
  var interruptedBySetextHeading = false;
  // Eat until we hit something that ends a paragraph.
  l_done:
  while (!parser.isDone) {
    if (preserveSpace) {
      //Look ahead and merge empty paragraphs following it
      while (const EmptyBlockSyntax().canParse(parser)) {
        childLines.add(parser.current.content);
        parser.advance();
        if (parser.isDone) break l_done;
      }
    }

    final syntax = interruptedBy(parser);
    if (syntax != null) {
      interruptedBySetextHeading = syntax is SetextHeaderSyntax;
      break;
    }
    childLines.add(parser.current.content);
    parser.advance();
  }

  // It is not a paragraph, but a setext heading.
  if (interruptedBySetextHeading) {
    return null;
  }

  final content = childLines.join('\n'),
    contents = UnparsedContent(preserveSpace ? content: content.trimRight());
  return Element('p', [contents]);
}