Bug: assert self._pageseq != 0

[chrisgrieser]

Hi, thanks again for pdfannots! I recently encountered a small issue where an unsupported annotation type completely shut down the annotation extraction. While it's understandable that not every fancy annotation type can be extracted, pdfannots shouldn't completely abort, bur rather simply skip the annotation.

It took me a bit to find the problematic annotation, which was even exacerbated by the fact that it wasn't an annotation visible in normal PDF readers, but probably some result of a bad quality PDF OCR scan.

The error was: WARNING: Unsupported annotation subtype: /'Popup'

[0xabu]

pdfannots shouldn't completely abort, bur rather simply skip the annotation.

That's exactly the intention -- it should be just a warning, but it shouldn't prevent extraction of any other annotations. From your description it sounds like pdfannots failed to produce any output until you removed the problematic annotation. Is that correct? Are you able to share the affected PDF?

[chrisgrieser]

sure, here is the warning message and the pdf:

extract.pdf

WARNING: Unsupported annotation subtype: /'Popup'
WARNING: Unsupported annotation subtype: /'Popup'
Traceback (most recent call last):
  File "/opt/homebrew/bin/pdfannots", line 8, in <module>
    sys.exit(main())
  File "/opt/homebrew/lib/python3.9/site-packages/pdfannots/cli.py", line 141, in main
    doc = process_file(
  File "/opt/homebrew/lib/python3.9/site-packages/pdfannots/__init__.py", line 472, in process_file
    page.annots.sort()
  File "/opt/homebrew/lib/python3.9/site-packages/pdfannots/types.py",
 line 226, in __lt__
    return self.pos < other.pos
  File "/opt/homebrew/lib/python3.9/site-packages/pdfannots/types.py", line 182, in __lt__
    assert self._pageseq != 0
AssertionError

[0xabu]

Ok, so the warning messages are a red herring here, the real issue is the assertion failure -- looks like one of the (supported) annotations wasn't encountered during the text traversal. I'll have a closer look on the weekend. Thanks for providing the sample!