Add specific tests for PurePosixPath and PureWindowsPath

[lengau]

Describe the changes

Adds tests specific to PurePosixPath and PureWindowsPath to catch issues like #1065

Tasks

• Unit tests added that reproduce the issue or prove feature is working
• Fix or feature added
• Entry to release notes added
• Pre-commit CI shows no errors
• Unit tests passing
• For documentation changes: The Read the Docs preview builds and looks as expected

[mrbean-bremen]

Thanks - I see the failing tests... is_reserved has been overwritten for fake pathlib.Path (for Python >= 3.12), but obviously not for Windows/PosixPath. I haven't checked that recursion under Windows with the joinpath test yet, that seems worse...

I will have a look over the weekend, unless you are going to fix it yourself :)

[mrbean-bremen]

@lengau: I added a commit with a fix for the reserved names to this PR (didn't want to copy the tests, or push the fix before the tests).

I wrote a spin-off issue for the joinpath problem under Windows and commented out the failing test for Windows.
I added a workaround for the recursion, so that will not happen anymore, but the test still fails - this turned out to be a bit more complicated.

Please check if that works for you.

[mrbean-bremen]

Ok, turned out the joinpath problem was easy to fix, I just made a mistake last time I tried it.
I have added an extra commit with the fix.

I'm planning to make a new release with these fixes (and with the official 3.13 support that I also added, as Python 3.13 was released today) soon - please check if this works for you.

[lengau]

@mrbean-bremen thanks for doing this! I was meaning to get to it this weekend but ended up being busy with other things. These fixes work for me on my Linux machine.

[mrbean-bremen]

I was meaning to get to it this weekend but ended up being busy with other things

Sounds familiar...

These fixes work for me on my Linux machine

Ok, I'm going to merge this and make a new release tonight - thanks!