Add missing function parameter names of pybind11 generated functions

[atouminet]

Fixes #2220

[nate-sime]

Is there a reason this isn't automatically available through pybind11? Maintaining these signatures could be cumbersome.

[atouminet]

I guess it is just not possible. From the pybind11 perspective, the function to wrap is just an object wrapping a function pointer. In C++ these pointers do not store the names of the function arguments.

One thing that helps with maintainability though is that pybind11 will run some static asserts to check if the number of arguments matches the number of py::arg defined in the code, such that if some arguments are added or removed from the C++ functions, not updating the wrappers will result in a build error. However swapping or renaming arguments will require manual intervention.

The same could be said for the C++ API documentation that is not translated automatically to the python API.
I guess that's just how it is when working with multiple languages.

[nate-sime]

I like the idea. Also for some reason your IDE or code linting has over formatted your code.

[atouminet]

Are you sure about the formatting? I made sure to run clang-format on each file. Just checked again and not seeing any diffs compared to the current version.

[jhale]

https://github.com/FEniCS/dolfinx/runs/6676578989?check_suite_focus=true

The formatting is OK according to the CI.

[nate-sime]

This is definitely helpful for users, I just worry about maintenance.

[garth-wells]

@atouminet could you resolve the merge conflict?

[atouminet]

@garth-wells just rebased the PR and resolved the conflicts.