Add Julia tests for LibTrixi.jl

[sloede]

Right now, only the C Interface is really tested. If we want LibTrixi.jl to be considered also as a standalone package, we should add regular Julia tests as well.

[benegee]

Just a quick note: I started reading up on this and implemented some initial pieces in a branch (which is currently not up to date though)

[benegee]

Julia-test testing the C interface: #68

[benegee]

Similar to the current C / Fortran test we could run a libelexir as explained in README.md

Do we want more, using Test.jl?

[sloede]

The problem is that I don't think it is possible to track coverage for the Julia functions when they are invoked from the C/Fortran library. Therefore, we do not know if everything implemented here is tested properly. Thus I'd propose to add some regular Julia tests (like we have in Trixi.jl), which exercise at least all functions defined in api_c.jl. This should then cover most/all functions defined elsewhere as well.

An advantage of separate Julia testing everything is that it will immediately give us a hint if something is broken on the Julia side or in the C/Julia interface itself.

[benegee]

💡

[benegee]

Reminder:
Check trixi_version_julia_jl() and trixi_version_julia_extended_jl()