What are these tests for ?

[ICONationDevTeam]

https://github.com/curvefi/curve-contract/blob/b0bbf77f8f93c9c5f4e415bce9cd71f0cdee960e/tests/pools/common/unitary/test_claim_fees.py#L19-L27

In simpler terms :

admin_fee = A - B

and the test is :

admin_fee + B == A

Whatever swap.balance() and swap.balances(i) returns, the result will always be true.