Improved navigation type safety. (#256)

EranBoudjnah · Sep 12, 2024 · fe705b9 · fe705b9
1 parent 47c3b9d
commit fe705b9
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Showing 10 changed files with 57 additions and 19 deletions.
diff --git a/app/src/main/java/com/mitteloupe/whoami/di/HistoryUiModule.kt b/app/src/main/java/com/mitteloupe/whoami/di/HistoryUiModule.kt
@@ -1,6 +1,7 @@
 package com.mitteloupe.whoami.di
 
 import androidx.fragment.app.Fragment
+import com.mitteloupe.whoami.architecture.presentation.navigation.PresentationNavigationEvent
 import com.mitteloupe.whoami.architecture.ui.binder.ViewStateBinder
 import com.mitteloupe.whoami.architecture.ui.navigation.mapper.NavigationEventToDestinationMapper
 import com.mitteloupe.whoami.architecture.ui.view.ViewsProvider
@@ -17,12 +18,15 @@ import dagger.hilt.InstallIn
 import dagger.hilt.android.components.FragmentComponent
 import javax.inject.Named
 
+private typealias NavigationMapper = NavigationEventToDestinationMapper<PresentationNavigationEvent>
+
 @Module
 @InstallIn(FragmentComponent::class)
 object HistoryUiModule {
     @Provides
+    @JvmSuppressWildcards
     @Named(HistoryFragment.NAVIGATION_MAPPER_NAME)
-    fun providesHistoryDestinationToUiMapper(): NavigationEventToDestinationMapper =
+    fun providesHistoryDestinationToUiMapper(): NavigationMapper =
         HistoryNavigationEventToDestinationMapper()
 
     @Provides

diff --git a/app/src/main/java/com/mitteloupe/whoami/di/HomeUiModule.kt b/app/src/main/java/com/mitteloupe/whoami/di/HomeUiModule.kt
@@ -3,6 +3,8 @@ package com.mitteloupe.whoami.di
 import android.content.Context
 import android.content.res.Resources
 import com.mitteloupe.whoami.analytics.Analytics
+import com.mitteloupe.whoami.architecture.presentation.navigation.PresentationNavigationEvent
+import com.mitteloupe.whoami.architecture.ui.navigation.mapper.NavigationEventToDestinationMapper
 import com.mitteloupe.whoami.coroutine.CoroutineContextProvider
 import com.mitteloupe.whoami.home.presentation.viewmodel.HomeViewModel
 import com.mitteloupe.whoami.home.ui.di.HomeDependencies
@@ -38,6 +40,7 @@ object HomeUiModule {
     fun providesConnectionDetailsToUiMapper() = ConnectionDetailsToUiMapper()
 
     @Provides
+    @Suppress("UNCHECKED_CAST")
     fun providesHomeDependencies(
         homeViewModel: HomeViewModel,
         homeViewStateToUiMapper: HomeViewStateToUiMapper,
@@ -51,7 +54,7 @@ object HomeUiModule {
         homeViewModel,
         homeViewStateToUiMapper,
         connectionDetailsToUiMapper,
-        homeNavigationMapper,
+        homeNavigationMapper as NavigationEventToDestinationMapper<PresentationNavigationEvent>,
         homeNotificationMapper,
         errorToUiMapper,
         coroutineContextProvider,

diff --git a/...a/com/mitteloupe/whoami/ui/navigation/mapper/HistoryNavigationEventToDestinationMapper.kt b/...a/com/mitteloupe/whoami/ui/navigation/mapper/HistoryNavigationEventToDestinationMapper.kt
@@ -6,8 +6,11 @@ import com.mitteloupe.whoami.architecture.ui.navigation.exception.UnhandledDesti
 import com.mitteloupe.whoami.architecture.ui.navigation.mapper.NavigationEventToDestinationMapper
 import com.mitteloupe.whoami.architecture.ui.navigation.model.UiDestination
 
-class HistoryNavigationEventToDestinationMapper : NavigationEventToDestinationMapper {
-    override fun toUi(navigationEvent: PresentationNavigationEvent): UiDestination =
+class HistoryNavigationEventToDestinationMapper :
+    NavigationEventToDestinationMapper<PresentationNavigationEvent>(
+        PresentationNavigationEvent::class
+    ) {
+    override fun mapTypedEvent(navigationEvent: PresentationNavigationEvent): UiDestination =
         when (navigationEvent) {
             is Back -> backUiDestination()
             else -> throw UnhandledDestinationException(navigationEvent)

diff --git a/...java/com/mitteloupe/whoami/ui/navigation/mapper/HomeNavigationEventToDestinationMapper.kt b/...java/com/mitteloupe/whoami/ui/navigation/mapper/HomeNavigationEventToDestinationMapper.kt
@@ -4,8 +4,6 @@ import android.content.Context
 import android.content.Intent
 import com.google.android.gms.oss.licenses.OssLicensesMenuActivity
 import com.mitteloupe.whoami.analytics.Analytics
-import com.mitteloupe.whoami.architecture.presentation.navigation.PresentationNavigationEvent
-import com.mitteloupe.whoami.architecture.ui.navigation.exception.UnhandledDestinationException
 import com.mitteloupe.whoami.architecture.ui.navigation.mapper.NavigationEventToDestinationMapper
 import com.mitteloupe.whoami.architecture.ui.navigation.model.UiDestination
 import com.mitteloupe.whoami.home.presentation.navigation.HomePresentationNavigationEvent
@@ -19,12 +17,11 @@ class HomeNavigationEventToDestinationMapper(
     private val activityContext: Context,
     private val ossLicensesMenuIntentProvider: Context.(Class<out Any>) -> Intent =
         { javaClass -> Intent(this, javaClass) }
-) : NavigationEventToDestinationMapper {
-    override fun toUi(navigationEvent: PresentationNavigationEvent): UiDestination =
-        when (navigationEvent) {
-            is HomePresentationNavigationEvent -> navigationEvent.toUiDestination()
-            else -> throw UnhandledDestinationException(navigationEvent)
-        }
+) : NavigationEventToDestinationMapper<HomePresentationNavigationEvent>(
+    HomePresentationNavigationEvent::class
+) {
+    override fun mapTypedEvent(navigationEvent: HomePresentationNavigationEvent): UiDestination =
+        navigationEvent.toUiDestination()
 
     private fun HomePresentationNavigationEvent.toUiDestination(): UiDestination = when (this) {
         is OnSavedDetails -> history(highlightedIpAddress)

diff --git a/.../com/mitteloupe/whoami/ui/navigation/mapper/HomeNavigationEventToDestinationMapperTest.kt b/.../com/mitteloupe/whoami/ui/navigation/mapper/HomeNavigationEventToDestinationMapperTest.kt
@@ -120,7 +120,8 @@ class HomeNavigationEventToDestinationMapperTest {
         assertThat(
             actualException.message,
             matchesPattern(
-                "^Navigation to PresentationNavigationEvent\\\$MockitoMock\\\$\\w+ was not handled.$"
+                "^Navigation to PresentationNavigationEvent\\\$MockitoMock\\\$\\w+ " +
+                    "was not handled.$"
             )
         )
     }

diff --git a/...mitteloupe/whoami/architecture/ui/navigation/mapper/NavigationEventToDestinationMapper.kt b/...mitteloupe/whoami/architecture/ui/navigation/mapper/NavigationEventToDestinationMapper.kt
@@ -1,8 +1,29 @@
 package com.mitteloupe.whoami.architecture.ui.navigation.mapper
 
 import com.mitteloupe.whoami.architecture.presentation.navigation.PresentationNavigationEvent
+import com.mitteloupe.whoami.architecture.ui.navigation.exception.UnhandledDestinationException
 import com.mitteloupe.whoami.architecture.ui.navigation.model.UiDestination
+import kotlin.reflect.KClass
 
-interface NavigationEventToDestinationMapper {
-    fun toUi(navigationEvent: PresentationNavigationEvent): UiDestination
+abstract class NavigationEventToDestinationMapper<in EVENT : PresentationNavigationEvent>(
+    private val kotlinClass: KClass<EVENT>
+) {
+    fun toUi(navigationEvent: PresentationNavigationEvent): UiDestination = when {
+        kotlinClass.isInstance(navigationEvent) -> {
+            @Suppress("UNCHECKED_CAST")
+            mapTypedEvent(navigationEvent as EVENT)
+        }
+
+        else -> {
+            mapGenericEvent(navigationEvent) ?: throw UnhandledDestinationException(
+                navigationEvent
+            )
+        }
+    }
+
+    protected abstract fun mapTypedEvent(navigationEvent: EVENT): UiDestination
+
+    protected open fun mapGenericEvent(
+        navigationEvent: PresentationNavigationEvent
+    ): UiDestination? = null
 }
diff --git a/...itecture/ui/src/main/java/com/mitteloupe/whoami/architecture/ui/view/BaseComposeHolder.kt b/...itecture/ui/src/main/java/com/mitteloupe/whoami/architecture/ui/view/BaseComposeHolder.kt
@@ -14,7 +14,7 @@ import com.mitteloupe.whoami.coroutine.CoroutineContextProvider
 abstract class BaseComposeHolder<VIEW_STATE : Any, NOTIFICATION : PresentationNotification>(
     private val viewModel: BaseViewModel<VIEW_STATE, NOTIFICATION>,
     private val coroutineContextProvider: CoroutineContextProvider,
-    private val navigationMapper: NavigationEventToDestinationMapper,
+    private val navigationMapper: NavigationEventToDestinationMapper<PresentationNavigationEvent>,
     private val notificationMapper: NotificationToUiMapper
 ) {
 

diff --git a/architecture/ui/src/main/java/com/mitteloupe/whoami/architecture/ui/view/BaseFragment.kt b/architecture/ui/src/main/java/com/mitteloupe/whoami/architecture/ui/view/BaseFragment.kt
@@ -19,6 +19,8 @@ import com.mitteloupe.whoami.architecture.ui.navigation.mapper.NavigationEventTo
 import kotlinx.coroutines.CoroutineScope
 import kotlinx.coroutines.launch
 
+private typealias NavigationMapper = NavigationEventToDestinationMapper<PresentationNavigationEvent>
+
 abstract class BaseFragment<VIEW_STATE : Any, NOTIFICATION : PresentationNotification> :
     Fragment,
     ViewsProvider {
@@ -29,7 +31,7 @@ abstract class BaseFragment<VIEW_STATE : Any, NOTIFICATION : PresentationNotific
 
     abstract val viewStateBinder: ViewStateBinder<VIEW_STATE, ViewsProvider>
 
-    abstract val navigationEventToDestinationMapper: NavigationEventToDestinationMapper
+    abstract val navigationEventToDestinationMapper: NavigationMapper
 
     open val navController: NavController
         get() = findNavController()

diff --git a/history/ui/src/main/java/com/mitteloupe/whoami/history/ui/view/HistoryFragment.kt b/history/ui/src/main/java/com/mitteloupe/whoami/history/ui/view/HistoryFragment.kt
@@ -10,6 +10,7 @@ import androidx.recyclerview.widget.RecyclerView
 import com.google.android.material.appbar.MaterialToolbar
 import com.mitteloupe.whoami.analytics.Analytics
 import com.mitteloupe.whoami.analytics.event.Click
+import com.mitteloupe.whoami.architecture.presentation.navigation.PresentationNavigationEvent
 import com.mitteloupe.whoami.architecture.presentation.notification.PresentationNotification
 import com.mitteloupe.whoami.architecture.ui.binder.ViewStateBinder
 import com.mitteloupe.whoami.architecture.ui.navigation.mapper.NavigationEventToDestinationMapper
@@ -26,6 +27,8 @@ import dagger.hilt.android.AndroidEntryPoint
 import javax.inject.Inject
 import javax.inject.Named
 
+private typealias NavigationMapper = NavigationEventToDestinationMapper<PresentationNavigationEvent>
+
 @AndroidEntryPoint
 class HistoryFragment :
     BaseFragment<HistoryViewState, PresentationNotification>(R.layout.fragment_history),
@@ -37,8 +40,9 @@ class HistoryFragment :
     override lateinit var viewModel: HistoryViewModel
 
     @Inject
+    @JvmSuppressWildcards
     @Named(NAVIGATION_MAPPER_NAME)
-    override lateinit var navigationEventToDestinationMapper: NavigationEventToDestinationMapper
+    override lateinit var navigationEventToDestinationMapper: NavigationMapper
 
     @Inject
     lateinit var recordDeletionToPresentationMapper: HistoryRecordDeletionToPresentationMapper

diff --git a/home/ui/src/main/java/com/mitteloupe/whoami/home/ui/di/HomeDependencies.kt b/home/ui/src/main/java/com/mitteloupe/whoami/home/ui/di/HomeDependencies.kt
@@ -1,6 +1,7 @@
 package com.mitteloupe.whoami.home.ui.di
 
 import com.mitteloupe.whoami.analytics.Analytics
+import com.mitteloupe.whoami.architecture.presentation.navigation.PresentationNavigationEvent
 import com.mitteloupe.whoami.architecture.ui.navigation.mapper.NavigationEventToDestinationMapper
 import com.mitteloupe.whoami.architecture.ui.notification.mapper.NotificationToUiMapper
 import com.mitteloupe.whoami.architecture.ui.view.BaseComposeHolder
@@ -12,11 +13,13 @@ import com.mitteloupe.whoami.home.ui.mapper.ConnectionDetailsToUiMapper
 import com.mitteloupe.whoami.home.ui.mapper.ErrorToUiMapper
 import com.mitteloupe.whoami.home.ui.mapper.HomeViewStateToUiMapper
 
+private typealias NavigationMapper = NavigationEventToDestinationMapper<PresentationNavigationEvent>
+
 data class HomeDependencies(
     val homeViewModel: HomeViewModel,
     val homeViewStateToUiMapper: HomeViewStateToUiMapper,
     val connectionDetailsToUiMapper: ConnectionDetailsToUiMapper,
-    private val homeNavigationMapper: NavigationEventToDestinationMapper,
+    private val homeNavigationMapper: NavigationMapper,
     private val homeNotificationMapper: NotificationToUiMapper,
     val errorToUiMapper: ErrorToUiMapper,
     val coroutineContextProvider: CoroutineContextProvider,