MAINT: fix mypy type output

[pubpub-zz]

closes #2798

[codecov]

Codecov Report

Attention: Patch coverage is 96.29630% with 3 lines in your changes missing coverage. Please review.

Project coverage is 95.83%. Comparing base (799630d) to head (4dd1444).
Report is 70 commits behind head on main.

Files with missing lines	Patch %	Lines
pypdf/_page.py	95.94%	3 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #2799      +/-   ##
==========================================
- Coverage   95.86%   95.83%   -0.03%     
==========================================
  Files          51       51              
  Lines        8528     8544      +16     
  Branches     1691     1692       +1     
==========================================
+ Hits         8175     8188      +13     
- Misses        209      212       +3     
  Partials      144      144              

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

[stefan6419846]

I am not completely sure about this - using private members in the public API does not feel right.

[pubpub-zz]

I am not completely sure about this - using private members in the public API does not feel right.

Can you please clarify: keys and items are public for _VirtualListImages.
if the issue is _VirtualListImages, should we rename it into VirtualListImages. this may have more impact and will make _VirtualListImages too visible without any advantage: I would not like to create a new subject of discussion such as the one we had on filters/LZWDecode

However, having a library fully compatible with mypy worth the commit

[stefan6419846]

In my opinion, it does not make sense to have a type hint referencing _VirtualListImages while this class is both not exposed publicly and even has a leading underscore to indicate it is private - such cases should only occur for the internal API. (ImageFile never being available as a public class is a similar issue in my opinion, but at least not prefixed by an underscore - the general issue is the same.)

[pubpub-zz]

Based on your comments:

• I renamed _VirtualListImages to VirtualListImages
• I moved ImageFile to make it public.
• I broke the inheritance between ImageFile with File and made it obsolete(never used out of ImageFile) in order to have a standalone module
• I also moved PIL import in _page to global in order to use (PIL.Image.)Image type

[stefan6419846]

I also moved PIL import in _page to global in order to use (PIL.Image.)Image type

Isn't this a breaking change for users which do not have Pillow installed?

[pubpub-zz]

I also moved PIL import in _page to global in order to use (PIL.Image.)Image type

Isn't this a breaking change for users which do not have Pillow installed?

No: the error is reported only when calling replace (as it used to be) There is no change in behavior

[stefan6419846]

I have reworded some of the docs.

Additionally, the ImageFile and VirtualListImages classes are still part of a private module only without being exposed in the __init__.py file. We should expose them there to allow users to actually refer to them in their own type hints if required.

[pubpub-zz]

Additionally, the ImageFile and VirtualListImages classes are still part of a private module only without being exposed in the __init__.py file. We should expose them there to allow users to actually refer to them in their own type hints if required.

ImageFile and VirtualListImages are not classes that a user should create instances from : as such I see no reason for them to be part of the __init__.py

The objective is just to fix mypy and the test report in the issue was positive

[stefan6419846]

Okay, let's keep this for now - except for the other remark regarding finally which still should be fixed.