Adding fixtures to Basis tests

[chris-langfield]

From #818, basis tests are now parametrized over a list of Basis objects instantiated with parameters that are stored in tests/_basis_util, e.g.

ASPIRE-Python/tests/test_FBbasis2D.py

Line 24 in 8720ce2

test_bases = [FBBasis2D(L, dtype=dtype) for L, dtype in basis_params_2d]

Instead of parametrizing test functions over the basis objects we should parametrize over the parameters themselves and create a fixture(s) to generate the basis objects.

Two things to note:

• FLEBasis2D FLE Basis #693 parametrizes over a variable the other bases do not, namely epsilon, which is an __init__ parameter
• This fixture or fixtures will have to interact with the UniversalBasisMixin class in _basis_util. The test functions in that class will have to accept a fixture rather than just a Basis. The fixture could be defined at a very high level in _basis_util.py (giving this class access to it), or the fixtures would have to be made available to it using pytest.fixture(... scope="session") or similar.

[chris-langfield]

It was also discussed in #693 that this could open a way for fixture-izing some of the data loading/generation functions (e.g. create_images in FLEBasis2D, once merged).