test.py does not honor $OPENMODELICALIBRARY

[bilderbuchi]

I am currently running OMLT in a Docker container with a custom image based on openmodelica/openmodelica:v1.21.0-ompython, with the intention to test a local package.

To "install" my package as per the README, based on https://openmodelica.org/doc/OpenModelicaUsersGuide/latest/faq.html?highlight=openmodelicalibrary#openmodelica-general and https://openmodelica.org/doc/OpenModelicaUsersGuide/latest/packagemanager.html#overview-of-basic-modelica-package-management-concepts, I append the location of my package to the environment variable OPENMODELICALIBRARY. (At first, it was not clear to me how to "install" a package that is not available in the package manager)

When loading a model from the package using omc, this works as expected (except for an unrelated error fixed in OM master OpenModelica/OpenModelica#10564)

$ echo $OPENMODELICALIBRARY
/home/openmodelicausers/repo
$ omc --instClass=MyPackage.Examples.MyExample
...

Expected behaviour

For test.py to pick up and use the value of $OPENMODELICALIBRARY

Observed behaviour

However, test.py does not seem to honor the content of that environment variable:

$ cat ../repo/CI_OMLT.json
[
    {
        "library": "MyPackage",
        "libraryVersion": ""
    }
]
$ python3 test.py ../repo/CI_OMLT.json
...
Failed to load library MyPackage {"default"}: Error: Failed to load package MyPackage (default) using MODELICAPATH /home/openmodelicausers/.openmodelica/libraries/.

It is clear that the MODELICAPATH is incomplete/wrong, considering the value of the env var OPENMODELICALIBRARY.

(As an aside, in the config file libraryVersion MUST be "", otherwise loading the package fails even though it has a matching version annotation in its package.mo.)

I suspect the reason is a hard-coded default for the --libraries argument at https://github.com/OpenModelica/OpenModelicaLibraryTesting/blob/9aa10d5f1091bb6d6eafb7f5e3cf6c9cfb164acd/test.py#L95C24-L95C33

Workaround

To work around this, one needs to manually pass the env var to test.py with --libraries $OPENMODELICALIBRARY. In some circumstances it was even necessary to manually find and prepend the "default" location: --libraries ~/.openmodelica/libraries/:$OPENMODELICALIBRARY, otherwise MSL etc. would not be loaded.

Possible solution

I think the default value for the libraries argument should be the value of $OPENMODELICALIBRARY. Only if that is empty/undefined, maybe the current hard-coded /home/openmodelicausers/.openmodelica/libraries/ might be appropriate, but I don't know enough about the inner workings of omc to assess if that would do that internally, anyway.