PcapReader_metaclass: Refactor open

[antoniovazquezblanco]

Checklist:

• If you are new to Scapy: I have checked CONTRIBUTING.md (esp. section submitting-pull-requests)
• I squashed commits belonging together
• I added unit tests or explained why they are not relevant
• I executed the regression tests (using cd test && ./run_tests or tox)
• If the PR is still not finished, please create a Draft Pull Request

I was thinking on being able to provide feedback on progress while reading PCAP files. I looked at the code of the reader metaclass an thought it could be refactored to be a little simpler to understand...

This changes introduce a behaviour change so this PR is kind not necessary at all, changes the behaviour and all in order to maybe make the code slightly more readable...

Let me know if this is clearly a no go or if there may be a chance.

Thanks!

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 81.55%. Comparing base (c15a670) to head (4bc91a2).
Report is 5 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #4661      +/-   ##
==========================================
- Coverage   81.55%   81.55%   -0.01%     
==========================================
  Files         359      359              
  Lines       86557    86559       +2     
==========================================
- Hits        70592    70589       -3     
- Misses      15965    15970       +5     

Files with missing lines	Coverage Δ
scapy/utils.py	73.56% <100.00%> (+0.02%)	⬆️

... and 6 files with indirect coverage changes

[gpotter2]

Hi, thanks for the PR !
I'm honnestly not convinced this is simpler, and tend to prefer the way it was before. Sorry :(

[antoniovazquezblanco]

Nothing to be sorry about :)

My reasoning was that this isolates the two things performed in the function and thus may be easier to read and or maybe perform testing.

Please, let me know if there is anything that may improve the idea or if you have some other feedback. Also, feel free to close this PR, as I said in my previous comment, I expected this to not be merged for various reasons.

Thanks for your time :)