MAINT: Handle XML error when reading XmpInformation

[MartinThoma]

Closes #585

[codecov]

Codecov Report

Merging #1030 (e6c745e) into main (d1f2ed2) will decrease coverage by 0.03%.
The diff coverage is 71.42%.

@@            Coverage Diff             @@
##             main    #1030      +/-   ##
==========================================
- Coverage   89.93%   89.90%   -0.04%     
==========================================
  Files          24       24              
  Lines        4482     4488       +6     
  Branches      916      916              
==========================================
+ Hits         4031     4035       +4     
- Misses        308      310       +2     
  Partials      143      143              

Impacted Files	Coverage Δ
PyPDF2/xmp.py	88.17% <71.42%> (-0.66%)	⬇️

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[phoewass]

It would be nice if reader.xmp_metadata can have a non-strict mode.

[MartinThoma]

I guess "None" would then be a reasonable return value?

[phoewass]

Absolutely!

And thank you for maintaining PyPDF2, it looks in a way better shape.

[guillaume-uH57J9]

Consider including diagnostic information contained in the ExpactError object (line, offset, kind of XML issue)/

Example:

except ExpatError as e:
    print("Got some XML error. " + str(e))

[guillaume-uH57J9]

Thanks @MartinThoma for the fix.

I added a minor comment to include more diagnostic info in the exception.
Also as @phoewass said, a non-strict mode would be nice to have.
But this change is already better than the status quo, and this is a fairly minor issue, so so the change is already a good improvement as is.

Thanks for you work maintaining PyPDF2.

[MartinThoma]

Adding a non-strict mode (that passes the value down from the reader) touches more things than I initially thought. I think for the moment I'll leave this out.