Function nest_toc_tokens

markdown/extensions/toc.py:174–236

Given an unsorted list with errors and skips, return a nested one. [{'level': 1}, {'level': 2}] => [{'level': 1, 'children': [{'level': 2, 'children': []}]}] A wrong list is also converted: [{'level': 2}, {'level': 1}] => [{'level': 2, 'children

(toc_list)

def nest_toc_tokens(toc_list):
    """Given an unsorted list with errors and skips, return a nested one.

        [{'level': 1}, {'level': 2}]
        =>
        [{'level': 1, 'children': [{'level': 2, 'children': []}]}]

    A wrong list is also converted:

        [{'level': 2}, {'level': 1}]
        =>
        [{'level': 2, 'children': []}, {'level': 1, 'children': []}]
    """

    ordered_list = []
    if len(toc_list):
        # Initialize everything by processing the first entry
        last = toc_list.pop(0)
        last['children'] = []
        levels = [last['level']]
        ordered_list.append(last)
        parents = []

        # Walk the rest nesting the entries properly
        while toc_list:
            t = toc_list.pop(0)
            current_level = t['level']
            t['children'] = []

            # Reduce depth if current level < last item's level
            if current_level < levels[-1]:
                # Pop last level since we know we are less than it
                levels.pop()

                # Pop parents and levels we are less than or equal to
                to_pop = 0
                for p in reversed(parents):
                    if current_level <= p['level']:
                        to_pop += 1
                    else:  # pragma: no cover
                        break
                if to_pop:
                    levels = levels[:-to_pop]
                    parents = parents[:-to_pop]

                # Note current level as last
                levels.append(current_level)

            # Level is the same, so append to
            # the current parent (if available)
            if current_level == levels[-1]:
                (parents[-1]['children'] if parents
                 else ordered_list).append(t)

            # Current level is > last item's level,
            # So make last item a parent and append current as child
            else:
                last['children'].append(t)