fix(requests): initialize deck fields before the collector runs

apps/flipcash/features/messenger/src/main/kotlin/com/flipcash/app/messenger/internal/request/ChatRequestsViewModel.kt

@@ -66,6 +66,12 @@ internal class ChatRequestsViewModel @Inject constructor(
     /** The deck, front card first. Empty hides it. */
     val deck: StateFlow<List<PaymentRequest>> = _deck.asStateFlow()
 
+    // Above init: viewModelScope runs on Main.immediate, so the deck collector publishes before
+    // the constructor returns, and fields declared after init would still be null.
+    private var shownNow = _now.value
+    private var settle: Job? = null
+    private var settledDeck: List<PaymentRequest> = emptyList()
+
     init {
         viewModelScope.launch {
             combine(
@@ -89,10 +95,6 @@ internal class ChatRequestsViewModel @Inject constructor(
         }
     }
 
-    private var shownNow = _now.value
-    private var settle: Job? = null
-    private var settledDeck: List<PaymentRequest> = emptyList()
-
     /**
      * Puts [next] on the deck. A request ending moves it in the sort order; the deck keeps its
      * order for the ended look's fade first, and only then lets the list slide it into place.

apps/flipcash/features/messenger/src/test/kotlin/com/flipcash/app/messenger/internal/request/ChatRequestsViewModelTest.kt

@@ -0,0 +1,55 @@
+package com.flipcash.app.messenger.internal.request
+
+import com.flipcash.services.user.UserManager
+import com.flipcash.shared.chat.ChatCoordinator
+import com.flipcash.shared.chat.PaymentRequests
+import androidx.lifecycle.ViewModelStore
+import io.mockk.every
+import io.mockk.mockk
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.ExperimentalCoroutinesApi
+import kotlinx.coroutines.flow.MutableStateFlow
+import kotlinx.coroutines.test.UnconfinedTestDispatcher
+import kotlinx.coroutines.test.resetMain
+import kotlinx.coroutines.test.runTest
+import kotlinx.coroutines.test.setMain
+import org.junit.After
+import org.junit.Assert.assertTrue
+import org.junit.Before
+import org.junit.Test
+
+/**
+ * `viewModelScope` runs on `Main.immediate`, so the deck collector emits inside the constructor.
+ * An unconfined main dispatcher reproduces that: the ViewModel has to be fully initialized by then.
+ */
+@OptIn(ExperimentalCoroutinesApi::class)
+class ChatRequestsViewModelTest {
+
+    private val requests = mockk<PaymentRequests>(relaxed = true) {
+        every { state } returns MutableStateFlow(emptyMap())
+        every { missing } returns MutableStateFlow(emptySet())
+    }
+    private val chatCoordinator = mockk<ChatCoordinator>(relaxed = true)
+    private val userManager = mockk<UserManager>(relaxed = true)
+
+    @Before
+    fun setUp() {
+        Dispatchers.setMain(UnconfinedTestDispatcher())
+    }
+
+    @After
+    fun tearDown() {
+        Dispatchers.resetMain()
+    }
+
+    @Test
+    fun `constructs when the deck collector emits in place`() = runTest {
+        val store = ViewModelStore()
+        val viewModel = ChatRequestsViewModel(requests, chatCoordinator, userManager)
+        store.put("requests", viewModel)
+
+        assertTrue(viewModel.deck.value.isEmpty())
+        // Cancels the minute ticker, which would otherwise keep runTest from going idle.
+        store.clear()
+    }
+}