googletest/coroutines/crf_constraints.md
2024-02-14 18:17:24 +00:00

1.7 KiB

CRF Constraints

1

Test setup in coroutine => Test coroutine must run as soon as its constructed, so as to allow it to create mock objects, watches etc before the mock source runs. Also in phase 2, coroutine can create mock sources.

2

Mock args passed by ref => MUT must not do anything between making a mock call and the coroutine body receiving the args. Note that the coroutine CAN run during this period, since the args are owned by the mock source.

3

Mock return passed by ref => Test coroutine must not do anything between Return() and the mock source receiving the return value. Mock source could in principle run during this period, since coro owns the return object, but in practice it won't because it's waiting for the return value.

4

Updated cardinality state => coroutine must run so that it can do SATISFY(), RETIRE() or run to exit BEFORE allowing GMock/CotestWatcher code to query eg IsSatisfied() etc. This is extra_iteration_requested reason inside TestCoroutine::DestructionIterations().

5

Global mock handler finding => After getting an event that is a mock call, test coroutines must call DROP() ACCEPT() or RETURN() on the event before doing anything elase with the cotest UI. This is because the process of deciding which expectation or coroutine will handle the call is global and must complete before anything happens that could generate more mock calls.

6

True event sequence => Most of the time, a LAUNCH() or RETURN() should be followed by NEXT_EVENT() because they will usually lead to an event for the test coro to pick up and handle. There is an exception in the case of a second coroutine whose response is to exit. See test case ObserverQueue.