Don't add features to production code that are only intended for use during automated testing

For reasons already described under Test Seams, adding anything to production code that is solely intended for use during automated tests should be avoided.

" anti-pattern
IF is_unit_test_running = abap_true.
  "some logic here that runs only during unit tests
ENDIF.  

Note that test features intended to be executed by an end user, e.g. simulated posting or running a report in test mode, form part of the application domain and remain a valid use case.