[rtags] Allow to 'derive' rtags Since some releases, rtags (structure underlying uicfg) have selector and may be copied using something like: new_rtags = deepcopy(original_rtags) new_rtags.__module__ = __name__ new_rtags.__select__ = custom_selector The problem is that starting from that, both rtags wil diverge and changes in original_rtags won't be considered, while we usually want to set a few specific rules only in new_rtags. To fix this problem, this cset introduces the notion of "derivated/parent" rtag, eg: new_rtags = original_rtags.derive(__name__, custom_selector) Beside easier copying, when using the above method changes in original_rtags which are not overriden by new_rtags will be considered since it only hold its specific rules but look among its parent chain for non-found keys. Along the way, flake8 unittest_rtags. Closes #16164880

from __future__ import absolute_import
import markdown

import logging

log = logging.getLogger(__name__)


def markdown_publish(context, data):
    """publish a string formatted as MarkDown Text to HTML

    :type context: a cubicweb application object

    :type data: str
    :param data: some MarkDown text

    :rtype: unicode
    :return:
      the data formatted as HTML or the original data if an error occurred
    """
    md = markdown.Markdown()
    try:
        return md.convert(data)
    except:
        import traceback; traceback.print_exc()
        log.exception("Error while converting Markdown to HTML")
        return data