Add tag filter

[mezuzza]

This PR adds tag_filter as a metadata property which can be used to filter the
set of tags examined for versioning the project. More details can be found in #219.

The git changes in this PR are straightforward. The hg changes require a bit more context.

In order to tags, it was necessary to use hg log as it provides a --template argument to use
with the latesttag function. Technically hg's regex is a python style regex, but I didn't think
it prudent to depend on that exact implementation detail. Instead, I refactored the implementation
slightly so that we use hg log to extract the current commit and hg id is relegated to telling us
if the working tree is dirty.

This is a PR that's stacked on top of #224. For easy of review, I suggest you look at only the
most recent commit. All other changes are captured in #224.

Resolves #219

[netlify]

✅ Deploy Preview for pdm-backend-docs ready!

Name	Link
🔨 Latest commit	ea2afd0
🔍 Latest deploy log	https://app.netlify.com/sites/pdm-backend-docs/deploys/662fec35e96dc80008a2077e
😎 Deploy Preview	https://deploy-preview-225--pdm-backend-docs.netlify.app
📱 Preview on mobile	Toggle QR Code... Use your smartphone camera to open QR code link.

---

To edit notification comments on pull requests, go to your Netlify site configuration.

[mezuzza]

This is still missing tests. I thought I'd ask for an early review of the draft just to align on the approach.

I'll finish the tests next week and submit for review.

[frostming]

While I am okay with the implementation, please don't stack the PR with other changes not related to this PR.

[mezuzza]

Sure, I'm used to stacking changes and submitting only once the parent has been submitted. I'll pull the changes out this week and separate them.

Also, sorry for the delay, but I've been pretty busy and hadn't the time to get to this. Will do so in the next couple days.

[frostming]

You forgot to declare pytest_lazyfixture as a dependency

[mezuzza]

I'm confused. It's a part of the test dependencies in the pyproject.toml. Does it need to be elsewhere?

[frostming]

I'm confused. It's a part of the test dependencies in the pyproject.toml. Does it need to be elsewhere?

According to the README, you don't need to import anything, as it can be accessed via pytest.lazy_fixture

[mezuzza]

Just tried that. It unfortunately fails pyright as pytest.lazy_fixture is parsed as an object. I'm not sure if it would pass mypy or pyre.

Do you care about the type checker and do you have a preference here? I'd recommend just leaving it as is since it will reduce type issues in the future compared to pytest.lazy_fixture.

[frostming]

Do you care about the type checker and do you have a preference here? I'd recommend just leaving it as is since it will reduce type issues in the future compared to pytest.lazy_fixture.

As long as the CI statuses are all green I am ok

[mezuzza]

Done. Added a quick assertion, but otherwise it should be good.

[frostming]

Please rebase main branch

[mezuzza]

Done

[mezuzza]

I noticed that the tests were failing so I took a look. Turns out that they were failing because of two issues.

1. pytest.lazy_fixture wasn't working, so I swapped back to the explicit import.
2. ZoneInfo wasn't available until python 3.9, so 3.8 was failing. This has been fixed by using dateutil for the time zone.

[mezuzza]

Removed the pytest-lazy-fixture dependency and fixed the CI to install hg for use in testing. All the tests are passing now.