[Future Spherical Class] Add SArc

[ghiggi]

This PR implements the new SArc class

• Tests added
• Tests passed
• Passes git diff origin/main **/*py | flake8 --diff

[codecov]

Codecov Report

Merging #478 (6f338fd) into main (6ff3568) will increase coverage by 0.35%.
The diff coverage is 99.43%.

❗ Current head 6f338fd differs from pull request most recent head a681248. Consider uploading reports for the commit a681248 to get more accurate results

@@            Coverage Diff             @@
##             main     #478      +/-   ##
==========================================
+ Coverage   94.27%   94.62%   +0.35%     
==========================================
  Files          78       76       -2     
  Lines       12838    13701     +863     
==========================================
+ Hits        12103    12965     +862     
- Misses        735      736       +1     

Flag	Coverage Δ
unittests	94.62% <99.43%> (+0.35%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
pyresample/future/spherical/arc.py	95.93% <95.93%> (ø)
pyresample/future/spherical/__init__.py	100.00% <100.00%> (ø)
pyresample/future/spherical/point.py	100.00% <100.00%> (ø)
pyresample/spherical.py	92.63% <100.00%> (-0.04%)	⬇️
pyresample/test/test_sgeom/test_arc.py	100.00% <100.00%> (ø)
pyresample/test/test_sgeom/test_point.py	100.00% <100.00%> (ø)
pyresample/test/conftest.py	98.01% <0.00%> (-0.39%)	⬇️
pyresample/geometry.py	87.40% <0.00%> (-0.15%)	⬇️
pyresample/test/test_kd_tree.py	97.31% <0.00%> (-0.05%)	⬇️
pyresample/test/test_dask_ewa.py	98.94% <0.00%> (-0.01%)	⬇️
... and 13 more

Help us with your feedback. Take ten seconds to tell us how you rate us. Have a feature suggestion? Share it here.

[coveralls]

Coverage increased (+0.4%) to 94.174% when pulling 6f338fd on ghiggi:feature-sarc into 952cec6 on pytroll:main.

[djhoese]

I have a couple code cleanup suggestions, but otherwise this looks good to me. I assume all the math is correct.

[djhoese]

You could define these as fixtures in the class, but considering this module is specific to testing the SArc class maybe it would be better to define them outside the class. But also...if we assume these classes/instances are immutable then you could also leave them like this.

[ghiggi]

I will clean out the unit test when I will finalize it after the SPolygon behaviour.
I am not sure yet of all the behaviour ... and the current code helps me to work line by line

[djhoese]

Looks like some of the github suggestions from my comments or your other recent changes have messed a few things up. Pre-commit and stickler and the website building are all mad.

[ghiggi]

@djhoese I think now the code is ready for another round of review ;)

[djhoese]

One more suggestion/question, sorry.

[djhoese]

Looks like one of the tests is failing with the unstable dependencies. Not sure what's up with that.