Untangling Coroutine Testing

on YouTube ↗38m

" summary

Migrates projects to kotlinx.coroutines 1.6 testing APIs and shows concrete fixes: use runTest to get a TestDispatcher backed by a single TestCoroutineScheduler (never create more than one per test), prefer the standard dispatcher (it queues work) over unconfined (it enters eagerly), control time with advanceUntilIdle / advanceTimeBy / runCurrent, replace the Main dispatcher with setMain/resetMain for ViewModel tests, inject dispatchers to avoid races, and use Turbine for robust Flow testing.

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" chapters (9)

1. 0:00Introduction to coroutine testing
2. 1:54New coroutine testing APIs
3. 3:57Testing suspending functions
4. 6:25Understanding test scope
5. 8:11Standard vs unconfined test dispatchers
6. 14:49Injecting dispatchers in tests
7. 20:01Handling Android main dispatcher
8. 24:37Testing flows and state flows
9. 37:04Summary and resources

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