Add flexibility to nonconservative BCs

[MarcoArtiano]

This PR allows to have more flexibility when defining the boundary conditions for a set of equations with nonconservative terms. This issues has been discussed in #2175. Now the user can define his own boundary condition, considering that the function accepts both surface flux and the nonconservative flux. An example can be found in elixir_mhd_reflective_wall

[github-actions]

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[codecov]

Codecov Report

Attention: Patch coverage is 93.18182% with 3 lines in your changes missing coverage. Please review.

Project coverage is 96.87%. Comparing base (f586b0d) to head (c85aba7).
Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
src/basic_types.jl	62.50%	3 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #2200      +/-   ##
==========================================
- Coverage   96.87%   96.87%   -0.01%     
==========================================
  Files         490      490              
  Lines       39463    39485      +22     
==========================================
+ Hits        38229    38248      +19     
- Misses       1234     1237       +3     

Flag	Coverage Δ
unittests	96.87% <93.18%> (-0.01%)	⬇️

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[MarcoArtiano]

According to the way this feature has been implemented, the functions boundary_condition_slip_wall in shallow_water_wet_dry_1d.jl and shallow_water_wet_dry_2d.jl should have been modified accordingly.

CC @andrewwinters5000

[andrewwinters5000]

Thanks for tackling this @MarcoArtiano! The functionality works as discussed where it is on the user to put in the boundary conditions for the conservative and nonconservative terms and then combine them appropriately, i.e., scaling noncons with 0.5f0. This is the only aspect I am not a huge fan of, as it is related to how the nonconservative terms are implemented at interfaces and has nothing to do with boundary conditions.

Because of this, we should maybe document where this factor of 0.5f0 magically comes from in the new boundary condition routines (as it was documented beofre inside the compute boundary flux call).

What do you think @patrickersing ?

[DanielDoehring]

Thanks for this! The only thing that I suggest is using the little more verbose noncons_flux instead of noncons.

[ranocha]

What's the status of this PR? We will have a breaking release soon and it would be nice to include this improvement.

[andrewwinters5000]

What's the status of this PR? We will have a breaking release soon and it would be nice to include this improvement.

I will review it again today, but the feature itself has converged quite well. We have mainly been making small adjustments to the comments. It should (more or less) be good to go. What do you think @patrickersing ?

[andrewwinters5000]

LGTM!

[MarcoArtiano]

I will add the docs today and commit the last few changes. After that everything should be fine, as already mentioned by @andrewwinters5000.

[patrickersing]

What's the status of this PR? We will have a breaking release soon and it would be nice to include this improvement.

I will review it again today, but the feature itself has converged quite well. We have mainly been making small adjustments to the comments. It should (more or less) be good to go. What do you think @patrickersing ?

Yes, there are only a few minor changes remaining. So from my end this is ready to merge, once these have been addressed.

[ranocha]

Could you please also add a NEWS.md entry in the section of stuff that changed when updating to Trixi.jl v0.10?

[ranocha]

Thanks!

[JoshuaLampert]

codecov reports this function to be uncovered. Could you add a test for this, please?

[JoshuaLampert]

...oh, was already merged in the same second 😅

[ranocha]

Sorry, didn't see that. @MarcoArtiano Could you please create a new PR with this test?

[MarcoArtiano]

Oh sorry, yes, I'm gonna make a PR soon.