When geopandas is available, pyogrio expects pyproj to be available

[theroggy]

Since geopandas 1.0, geopandas-base doesn't imply anymore that pyproj will be installed as well.

But, pyogrio now expects it to be.

Noticed in #452.

[jorisvandenbossche]

Good point, we should update our importing of pyproj and provide a better error message if it is not available.

[jorisvandenbossche]

Although #452 already updates the one place where we import pyproj?

[theroggy]

Yes, after making this issue I noticed it was easy to just remove the import...

[theroggy]

Back to the drawing board... I added pyproj previously to the environment file to focus the test on the switch to libgdal-core and hadn't removed it yet. Now I removed it again in #452 quite some tests are failing because pyproj not being available leads to different behaviour in geopandas...

What is the way forward? Add pyproj as a dependency in the conda package or try further to get the tests running without pyproj?

[martinfleis]

When we allowed geopandas without pyproj, we had to change quite a lot of tests as the expected value for CRS changes to None.

If we want to properly do it here, we might need to follow the same model.

We should allow pyogrio without pyproj to support this model in geopandas so I wouldn't add it necessarily as a conda dependency.

[theroggy]

It should be OK now in #452: no more failing tests when pyproj is not available...