Infinite loop with custom list_item_pattern

[joserwan]

Mistune 2.x here.

I'm trying to add the character • (bullet, unicode u2022) as a list item marker :

mistune.BlockParser.LIST_START = re.compile('( {0,3})([\\*\\+\\u2022\\-]|\\d{1,9}[.)])(?:[ \\t]*|[ \\t][^\\n]+)\\n+')

This ends with an infinite loop in the methode _create_list_item_pattern, since it doesn't match any of the default markdown markers :

# mistune/block_parser.py:320
        if marker == '*':
            prefix = prefix + r'\*'
        elif marker == '+':
            prefix = prefix + r'\+'
        else:
            prefix = prefix + r'-'

I finally made it work with the following else case :

# mistune/block_parser.py:320
        if marker == '*':
            prefix = prefix + r'\*'
        elif marker == '+':
            prefix = prefix + r'\+'
        else:
            prefix = prefix + rf'{marker}'

Is there any risk to use a variable into the generated regex ? Is there any chance this change to be included in Mistune 2.x ?

[Hsiaoming Yang]

Actually this if else is not required:

prefix + re.escape(marker)

is enough

[Hsiaoming Yang]

v2.0.5 is released.