Compatibility with shapely 2.0 (remove usage of lgeos)

[jorisvandenbossche]

Rationale

See #2076.

It is actually relatively easy to remove the usage of shapely.geos.lgeos, which is removed in Shapely 2.0, as a first step to make cartopy compatible with Shapely 2.0 (without making use of new features).

I think this should actually be a safe change to include in a 0.21.1 bug-fix release, in case that would be planned.

Now, while this is a necessary change to run the test suite with Shapely 2.0, there are still some other failures, but for things that potentially can be fixed on Shapely's side (see #2076 (comment) for details)

[greglucas]

@jorisvandenbossche, thanks for the patch! I agree that this seems reasonable for a patch release. Can you revert all the pins throughout the documentation?
ad1ec1a

Cartopy was not compatible with MPL 3.6 or Shapely 2.0, so we were trying to get ahead of the MPL 3.6 release. I am not opposed to turning this around for a quick v0.21.1 tag to remove the pin on Shapely though so more people can test.

[jorisvandenbossche]

Reverted the pins (and all required PRs on the Shapely side are now fixed)

[jorisvandenbossche]

The doc build failure seems unrelated?

[dopplershift]

I dug into the doc failure and it's from Matplotlib 3.6: matplotlib/matplotlib#24053.

[felixdivo]

The Shapely team just published version 2.0b1, so this might be a good point in time to publish this Cartopy improvement and (let the community) test them together. 😄

[jorisvandenbossche]

Yes, shapely 2.0b1 should contain all fixes to have this working.

You could replace the pip install git+https://github.com/shapely/shapely.git@main with pip install --pre

[felixdivo]

Is there an estimate on when the next version of Cartopy will be released? :)

[greglucas]

Not yet. We could make a patch release, but I think it'd be good if we settled on #2083 first to try and add that to the release.

[felixdivo]

That sounds reasonable. And as long as shapely 2.0 is not stable, this won't cause too many people to ask for cartopy to support it.

Thank you for the insight. 😄

[jorisvandenbossche]

Just a heads up that I am planning to release a final shapely 2.0 in a few days.

So it would be nice to either have a 0.21 patch release with this fix included, or a not to too distant timeline for 0.22

[greglucas]

@jorisvandenbossche, thanks for the heads up. Would you mind cherry-picking this commit over and targeting the v0.21.x branch? Then I can merge that and make a new patch release. That will be the easiest quick path since the 0.22 PR discussion has stalled (feel free to drop a comment over there if you have thoughts on speed vs ease-of-use for your library end-users).

[jorisvandenbossche]

Would you mind cherry-picking this commit over and targeting the v0.21.x branch? Then I can merge that and make a new patch release

-> opened #2110