Add unit tests for shields

[kuroidoruido]

The project is working but have a very big issue: there is no tests. Everything is tested by hand...

The goal here is to add unit tests to every shield

I can take a look!

[monil]

@kuroidoruido How about creating different issues for unit test cases for each module?
I can write cases for mappers.

[kuroidoruido]

@monil you right! I will create an issue for each testing point 😉

[kuroidoruido]

@monil I made the split. We now have 5 issues 🙂

@priyanka-debnath notice the scope of this issue is now limited to shields, but you can have a look on the other issues 😉

[NyorJa]

please do count me in also in this issue. Thanks