The reason for this being a separate package from
ouroboros-consensus-shelley and not just its testsuite, is that
ouroboros-consensus-cardano depends on the test code of Shelley to test the
Cardano chain, of which Shelley is a part.
This package contains:
src: test generators and test infrastructure for testing the integration of the Shelley ledger with the consensus layer. Not the actual tests.
test: the actual Shelley tests