Add missing reactive-completion tests for issue #135

foliary/src/commonTest/kotlin/dev/appoutlet/foliary/feature/taskdetail/TaskDetailScreenTest.kt

@@ -1,5 +1,8 @@
 package dev.appoutlet.foliary.feature.taskdetail
 
+import androidx.compose.runtime.getValue
+import androidx.compose.runtime.mutableStateOf
+import androidx.compose.runtime.setValue
 import androidx.compose.ui.test.ExperimentalTestApi
 import androidx.compose.ui.test.assertIsDisplayed
 import androidx.compose.ui.test.assertTextEquals
@@ -283,4 +286,31 @@ class TaskDetailScreenTest {
             .assertDoesNotExist()
         event shouldBe null
     }
+
+    @Test
+    fun `should toggle completion action when view data changes`() = runComposeUiTest {
+        val events = mutableListOf<TaskDetailEvent>()
+        var viewData by mutableStateOf(
+            TaskDetailViewData.Loaded(TaskDetailViewData.Loaded.TaskViewData.fixture())
+        )
+
+        setContent { TaskDetailScreen(viewData = viewData, onEvent = events::add) }
+
+        onNodeWithTag("TaskDetailScreen:MarkAsComplete")
+            .assertIsDisplayed()
+            .performClick()
+        events shouldBe listOf(TaskDetailEvent.MarkCompletedClicked)
+
+        viewData = TaskDetailViewData.Loaded(
+            viewData.task.copy(isComplete = true, completionDate = "21 Oct 2026")
+        )
+        waitForIdle()
+
+        onNodeWithTag("TaskDetailScreen:UnmarkAsComplete").assertIsDisplayed()
+        onNodeWithTag("TaskDetailScreen:MarkAsComplete").assertDoesNotExist()
+        onNodeWithTag("TaskDetailScreen:CompletionDate").assertIsDisplayed()
+
+        onNodeWithTag("TaskDetailScreen:UnmarkAsComplete").performClick()
+        events.last() shouldBe TaskDetailEvent.MarkNotCompletedClicked
+    }
 }

foliary/src/commonTest/kotlin/dev/appoutlet/foliary/feature/taskdetail/TaskDetailViewModelTest.kt

@@ -13,9 +13,11 @@ import dev.mokkery.mock
 import dev.mokkery.verify
 import dev.mokkery.verifySuspend
 import kotlinx.coroutines.delay
+import kotlinx.coroutines.flow.MutableStateFlow
 import kotlinx.coroutines.flow.flowOf
 import kotlin.test.Test
 import kotlin.time.Duration.Companion.milliseconds
+import kotlin.time.Instant
 import kotlin.uuid.Uuid
 
 class TaskDetailViewModelTest : ViewModelTest<TaskDetailViewModel, TaskDetailViewData, TaskDetailAction>() {
@@ -91,6 +93,31 @@ class TaskDetailViewModelTest : ViewModelTest<TaskDetailViewModel, TaskDetailVie
         }
     }
 
+    @Test
+    fun `should reflect completion changes emitted by repository`() {
+        val incompleteTask = Task.fixture(id = taskId, completionDate = null)
+        val completedTask = incompleteTask.copy(completionDate = Instant.parse("2026-10-21T10:00:00Z"))
+        val incompleteViewData = TaskDetailViewData.Loaded.TaskViewData.fixture(isComplete = false)
+        val completedViewData = TaskDetailViewData.Loaded.TaskViewData.fixture(
+            isComplete = true,
+            completionDate = "21 Oct 2026",
+        )
+        val tasks = MutableStateFlow<Task?>(incompleteTask)
+
+        every { mockTaskRepository.observeById(taskId) } returns tasks
+        every { mockTaskViewDataMapper(incompleteTask) } returns incompleteViewData
+        every { mockTaskViewDataMapper(completedTask) } returns completedViewData
+
+        test {
+            expectState(TaskDetailViewData.Loading)
+            expectState(TaskDetailViewData.Loaded(task = incompleteViewData))
+
+            tasks.value = completedTask
+
+            expectState(TaskDetailViewData.Loaded(task = completedViewData))
+        }
+    }
+
     @Test
     fun `should mark task as completed when mark completed is clicked`() {
         val task = Task.fixture(id = taskId)