Missing test cases for Event Services API parameter/return status combinations

[jphickey]

Is your feature request related to a problem? Please describe.
The following parameter/return combinations are not exercised by the Event Services functional test:

 + condition: CFE_EVS_Register[any]=>CFE_ES_BAD_ARGUMENT
 + condition: CFE_EVS_Register[any]=>CFE_EVS_APP_FILTER_OVERLOAD
 + condition: CFE_EVS_Register[any]=>CFE_EVS_APP_ILLEGAL_APP_ID
 + condition: CFE_EVS_Register[any]=>CFE_EVS_UNKNOWN_FILTER
 + condition: CFE_EVS_Register[any]=>CFE_SUCCESS
 + condition: CFE_EVS_ResetAllFilters[any]=>CFE_EVS_APP_ILLEGAL_APP_ID
 + condition: CFE_EVS_ResetAllFilters[any]=>CFE_EVS_APP_NOT_REGISTERED
 + condition: CFE_EVS_ResetFilter[any]=>CFE_EVS_APP_ILLEGAL_APP_ID
 + condition: CFE_EVS_ResetFilter[any]=>CFE_EVS_APP_NOT_REGISTERED
 + condition: CFE_EVS_SendEvent[any]=>CFE_EVS_APP_ILLEGAL_APP_ID
 + condition: CFE_EVS_SendEvent[any]=>CFE_EVS_APP_NOT_REGISTERED
 + condition: CFE_EVS_SendEventWithAppID[any]=>CFE_EVS_APP_NOT_REGISTERED
 + condition: CFE_EVS_SendTimedEvent[any]=>CFE_EVS_APP_ILLEGAL_APP_ID
 + condition: CFE_EVS_SendTimedEvent[any]=>CFE_EVS_APP_NOT_REGISTERED

Describe the solution you'd like
Ideally should be tested, but this may be difficult with the current cfe_testcase app because it uses event services to report test results.

Describe alternatives you've considered
Document why these cannot be tested in the current Caelum release, and rely on coverage testing to test these responses (which is already implemented)

Additional context
Part of/related to #1724 (each subsystem will be handled separately)

These should generally not be marked as covtest in the doxygen because they (theoretically) can be tested in a functional test, its just that the cfe_testcase app uses and registers with event services before starting tests, so any interference with this would prevent/conflict with normal test reporting. This is true for all calls to CFE_EVS_Register (because its already registered), and all items that return CFE_EVS_APP_ILLEGAL_APP_ID or CFE_EVS_APP_NOT_REGISTERED (which is really everything in the above list). These would all need a separate app/task that is not registered with EVS to accomplish.

Requester Info
Joseph Hickey, Vantage Systems, Inc.

[skliper]

Agree 100%, the registration success "test case" is by demonstration/use and all the errors will be traced to "analysis" which translates to coverage for now. Improvements can be implemented in the next round w/ additional test apps. Added the "functional" label to specifically track this sort of issue (and "unit-test" still generically identifies the issue as not applying to "production" code)

[jphickey]

Dependent on #1761 - all these EVS cases would require a companion/secondary test app that is not registered with EVS, in order to exercise the various EVS registration-related calls.