continuesAfterBlank function

bool continuesAfterBlank(List<String> before, String next)

Whether a blank line followed by next continues the block that before ends with, rather than separating two blocks.

It does when next is indented under a list item — a second paragraph or a fenced code block that belongs to the item, the shape of almost every step-by-step answer — or under a footnote definition. The owner is the nearest earlier line indented less than next; it continues the item exactly when the parser would nest next under it.

For the code that cuts a document into independently parsed pieces at blank lines: cutting here moved the item's code block out of the list, and parsed alone, every line of it kept the item's indentation.

Implementation

bool continuesAfterBlank(List<String> before, String next) {
  final indent = indentWidth(next);
  if (indent == 0) {
    return false;
  }
  for (var k = before.length - 1; k >= 0; k--) {
    final line = before[k];
    if (isBlank(line)) {
      continue;
    }
    if (indentWidth(line) >= indent) {
      continue;
    }
    final t = line.trimLeft();
    if (unorderedMarker(t) != null || orderedMarker(t) != null) {
      return true;
    }
    return indent >= 4 && t.startsWith('[^');
  }
  return false;
}