Kotlin Flow - StateFlow, SharedFlow, operators, testing
Provides Kotlin Flow reactive programming patterns including StateFlow/SharedFlow, operators like debounce/flatMapLatest, and Turbine testing. Use when creating or debugging reactive data streams in Kotlin code.
/plugin marketplace add pluginagentmarketplace/custom-plugin-kotlin/plugin install kotlin-assistant@pluginagentmarketplace-kotlinThis skill inherits all available tools. When active, it can use any tool Claude has access to.
assets/config.yamlassets/schema.jsonreferences/GUIDE.mdreferences/PATTERNS.mdscripts/validate.pyReactive programming with Kotlin Flow.
// Cold Flow - starts fresh for each collector
fun loadData(): Flow<Data> = flow {
emit(fetchData())
}
// Hot Flow - shared state
private val _state = MutableStateFlow(State())
val state: StateFlow<State> = _state.asStateFlow()
fun searchUsers(query: Flow<String>): Flow<List<User>> =
query
.debounce(300)
.filter { it.length >= 2 }
.distinctUntilChanged()
.flatMapLatest { term -> userRepository.search(term) }
.catch { emit(emptyList()) }
val dashboard: Flow<Dashboard> = combine(
userFlow,
ordersFlow,
notificationsFlow
) { user, orders, notifications ->
Dashboard(user, orders.size, notifications.count())
}
@Test
fun `flow emits values`() = runTest {
viewModel.state.test {
assertThat(awaitItem().isLoading).isFalse()
viewModel.load()
assertThat(awaitItem().isLoading).isTrue()
advanceUntilIdle()
assertThat(awaitItem().data).isNotNull()
}
}
| Issue | Resolution |
|---|---|
| Flow never emits | Add terminal operator (collect, first) |
| Stale data in UI | Use stateIn or shareIn properly |
Skill("kotlin-flow")
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