Class FootnoteBlockProcessor

markdown/extensions/footnotes.py:234–321

Find footnote definitions and store for later use.

class FootnoteBlockProcessor(BlockProcessor):
    """ Find footnote definitions and store for later use. """

    RE = re.compile(r'^[ ]{0,3}\[\^([^\]]*)\]:[ ]*(.*)$', re.MULTILINE)

    def __init__(self, footnotes: FootnoteExtension):
        super().__init__(footnotes.parser)
        self.footnotes = footnotes

    def test(self, parent: etree.Element, block: str) -> bool:
        return True

    def run(self, parent: etree.Element, blocks: list[str]) -> bool:
        """ Find, set, and remove footnote definitions. """
        block = blocks.pop(0)

        m = self.RE.search(block)
        if m:
            id = m.group(1)
            fn_blocks = [m.group(2)]

            # Handle rest of block
            therest = block[m.end():].lstrip('\n')
            m2 = self.RE.search(therest)
            if m2:
                # Another footnote exists in the rest of this block.
                # Any content before match is continuation of this footnote, which may be lazily indented.
                before = therest[:m2.start()].rstrip('\n')
                fn_blocks[0] = '\n'.join([fn_blocks[0], self.detab(before)]).lstrip('\n')
                # Add back to blocks everything from beginning of match forward for next iteration.
                blocks.insert(0, therest[m2.start():])
            else:
                # All remaining lines of block are continuation of this footnote, which may be lazily indented.
                fn_blocks[0] = '\n'.join([fn_blocks[0], self.detab(therest)]).strip('\n')

                # Check for child elements in remaining blocks.
                fn_blocks.extend(self.detectTabbed(blocks))

            footnote = "\n\n".join(fn_blocks)
            self.footnotes.setFootnote(id, footnote.rstrip())

            if block[:m.start()].strip():
                # Add any content before match back to blocks as separate block
                blocks.insert(0, block[:m.start()].rstrip('\n'))
            return True
        # No match. Restore block.
        blocks.insert(0, block)
        return False

    def detectTabbed(self, blocks: list[str]) -> list[str]:
        """ Find indented text and remove indent before further processing.

        Returns:
            A list of blocks with indentation removed.
        """
        fn_blocks = []
        while blocks:
            if blocks[0].startswith(' '*4):