Added fix for unstable element index (issue #223)

[erbsenmann]

Hi, I solved the issue described in #223 using this patch locally. With this adaption I was able to run my filter as expected.
Also added a smaller test than in the ticket.

Idea is to fill the index position in the ListContainer along with the parent and location instead of deriving it.
Like this eq on element can be left untouched.

[sergiocorreia]

Thanks for the PR, as well as for spotting the bug which felt quite subtle on a first pass. (Also, apologies for not spotting the issue beforehand, I somehow missed the email from Github).

The PR looks great, but is it possible to do a minor edit to the version.py file and bump it to 2.2.5? In that way, the github runner will be able to push it to PyPI (I tried to search for a way to edit the PR as a reviewer but can't seem to find one).

Thanks again!

[ickc]

is it possible to do a minor edit to the version.py file and bump it to 2.2.5?

I'd advise against this as so far this PR is standalone about 1 issue. Version bumping is about releasing a package which is not part of this issue or PR's job.

Put it in other words, it would be confusing if all PRs are asked to bump the version because it is possible that only after a few PRs there's a version release. And since that cannot be asked to all PRs, it is equally confusing to just ask some of them doing it.

[sergiocorreia]

Fair enough!