Footnotes module regression?

[npcole]

I've got a strange bug while using markdown as part of a flask app.

The following code works fine when running in the terminal:

import markdown
import markdown.extensions

value = """


This is a test.[^1]

[^1]: this is a footnote.

"""

result = markdown.markdown(value,
              extensions=[
                      'markdown.extensions.footnotes',
                      'markdown.extensions.tables',
                      'markdown.extensions.sane_lists',
                  ]
          )
print(result)

But when run as part of a Flask app I get the following error:

  File "/Users/nicholas/projects/quill/venv3.7/lib/python3.7/site-packages/markdown/core.py", line 388, in markdown
    return md.convert(text)
  File "/Users/nicholas/projects/quill/venv3.7/lib/python3.7/site-packages/markdown/core.py", line 269, in convert
    newRoot = treeprocessor.run(root)
  File "/Users/nicholas/projects/quill/venv3.7/lib/python3.7/site-packages/markdown/extensions/footnotes.py", line 388, in run
    footnotesDiv = self.footnotes.makeFootnotesDiv(root)
  File "/Users/nicholas/projects/quill/venv3.7/lib/python3.7/site-packages/markdown/extensions/footnotes.py", line 181, in makeFootnotesDiv
    self.parser.parseChunk(surrogate_parent, self.footnotes[id])
  File "/Users/nicholas/projects/quill/venv3.7/lib/python3.7/site-packages/markdown/blockparser.py", line 105, in parseChunk
    self.parseBlocks(parent, text.split('\n\n'))
  File "/Users/nicholas/projects/quill/venv3.7/lib/python3.7/site-packages/markdown/blockparser.py", line 123, in parseBlocks
    if processor.run(parent, blocks) is not False:
  File "/Users/nicholas/projects/quill/venv3.7/lib/python3.7/site-packages/markdown/blockprocessors.py", line 591, in run
    p = etree.SubElement(parent, 'p')
TypeError: SubElement() argument 1 must be xml.etree.ElementTree.Element, not Element

If I downgrade to markdown version 3.1, everything works as expected, but upgrading to anything after 3.2 triggers the exception.

Does anyone know what might be going on?

[mitya57]

I think it's the same issue as #950. Please read the discussion there. Changing the order of your imports might fix it.

[npcole]

Thank you, you are quite right. Putting the line

from defusedxml import ElementTree

right at the start of the application did fix this error. defusedxml really shouldn't behave in that way! Mutter mutter mutter!

[waylan]

Supposedly, this was fixed this in tiran/defusedxml#60 and tiran/defusedxml#63. According to their changelog, those changes should be available in difusedxml 0.8.0, whenever that is released.