Fix CasADi libs workaround for macOS wheels, update to CasADi 3.6.6 for Windows wheels

[agriyakhetarpal]

Description

I was going to split these into two PRs, but I decided that it would be fine to do it in the same one:

• This removes a workaround previously used to repair the wheels for Intel macOS devices. We will now have better compatibility with macOS version 10.13 and later. The M-series wheels still have something broken, so I will need to reach out to CasADi upstream again.
• For Windows, I bumped CasADi to version 3.6.6 in our registry at https://github.com/pybamm-team/casadi-vcpkg-registry and updated the baseline for our vcpkg configuration.

Type of change

Please add a line in the relevant section of CHANGELOG.md to document the change (include PR #) - note reverse order of PR #s. If necessary, also add to the list of breaking changes.

• Bug fix (non-breaking change which fixes an issue)

Key checklist:

• No style issues: $ pre-commit run (or $ nox -s pre-commit) (see CONTRIBUTING.md for how to set this up to run automatically when committing locally, in just two lines of code)
• All tests pass: $ python run-tests.py --all (or $ nox -s tests)
• The documentation builds: $ python run-tests.py --doctest (or $ nox -s doctests)

You can run integration tests, unit tests, and doctests together at once, using $ python run-tests.py --quick (or $ nox -s quick).

Further checks:

• Code is commented, particularly in hard-to-understand areas
• Tests added that prove fix is effective or that feature works

[agriyakhetarpal]

Wheel builds passing: https://github.com/agriyakhetarpal/PyBaMM/actions/runs/10601940680/job/29382886771.

Opened an issue about CasADi 3.6.6 in their feedstock: conda-forge/casadi-feedstock#114. Either way, it's not needed too much since 3.6.X releases maintain minor version compatibility and don't break in the ways we have noticed in #3100. We should be fine without it even if it takes slightly more time (since we don't distribute the IDAKLU solver in our conda-forge recipe anyway).

P.S. and it actually triggered a release PR, so we're good to go :)

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 99.42%. Comparing base (16e06f5) to head (94fde78).
Report is 206 commits behind head on develop.

Additional details and impacted files

@@           Coverage Diff            @@
##           develop    #4391   +/-   ##
========================================
  Coverage    99.42%   99.42%           
========================================
  Files          292      292           
  Lines        22215    22215           
========================================
  Hits         22087    22087           
  Misses         128      128           

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

[kratman]

Changes look fine, but I won't merge this yet since it sounds like you are still waiting on Anaconda and CasADi updates

[agriyakhetarpal]

Yes, let's hope that the update gets merged soon. We should be safe in general, though (PyBaMM on conda-forge will be released only after PyPI, so we always have time to update our recipe).

[kratman]

Yes, let's hope that the update gets merged soon. We should be safe in general, though (PyBaMM on conda-forge will be released only after PyPI, so we always have time to update our recipe).

If the CasADi/Anaconda issues don't get resolved soon, then we have to revert the change in the vcpkg registry for casadi correct?

[agriyakhetarpal]

No, we don't need to, because we can stall the PyBaMM conda-forge release during the delay. PyBaMM does not need the build-time (host) dependency on CasADi for its conda-forge recipe (because the IDAKLU solver is not compiled there yet), just the run-time dependency (which is fine with 3.6.X).

[agriyakhetarpal]

Also, no users have reported the IDAKLU solver's absence in conda-forge to us earlier. I had earlier noted somewhere that most people seem to be installing via PyPI, and that seems to still be the case: https://anaconda.org/conda-forge/pybamm/files. Let's wait for a few days before we merge this, nevertheless.

[kratman]

It is a bit off topic, but what needs to happen for IDAKLU to be included with conda-forge? If the switch to IDAKLU as the default solver ends up happening, then that is pretty critical

[agriyakhetarpal]

Oh, that's not off-topic, I had that in mind recently – if the switch to the IDAKLU solver being the default ends up happening, then pyidaklu will become a required dependency on PyBaMM, and we will need to create a new recipe for it to conda-forge via a pyidaklu-feedstock repository. Assuming that we make it the default in PyBaMM version 25.1 while also trying to unvendor it at the same time, we have the following three months and the next release cycle to set up a recipe for https://github.com/pybamm-team/pyidaklu and publish it on both PyPI and conda-forge.

cc: @santacodes

[agriyakhetarpal]

We can include the IDAKLU solver even right now in the PyBaMM recipe without having unvendored it – we just need to add the relevant build scripts and compile it the right way across platforms, and bump the build number (N.B., which is not the same as the version) – I've thought about it before and it isn't difficult, but it's better to do so after #4352 gets merged and becomes a part of a release (which would bring us back to the 25.1 release).

[agriyakhetarpal]

CasADi 3.6.6 is now up on conda-forge, too: https://anaconda.org/conda-forge/casadi/files. We can now merge this safely.

[agriyakhetarpal]

I see that the required check for auto-merge is just the RTD one, we should add the unit tests to this, at least, so that we don't auto-merge something in the future that can potentially fail.