Help with XS unit tests

We are working on some unit tests for HANA and we have two problems:

1. When running the tests on browser it uses the browser language as language for tests, as we are using text joins the language may affect the tests. Is it possible to force English to be used as language independently of the browser language?
2. We need to do some tests that involve currency conversion. The conversions are made automatically by the HANA Server. How can we isolate this behavior  to use in the unit tests?

Thanks and regards

Jefferson