Handle account switch in RootFlowNode instead of in presenters

PreferencesRootPresenter and HomePresenter were updating the latest session
in the session store directly, relying on RootNavStateFlow to trigger the
navigation as a side effect. Changing the current session is app-level
navigation, so it is now forwarded through a new `navigateToSession` callback
up to RootFlowNode, which performs the session store update.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

appnav/src/main/kotlin/io/element/android/appnav/LoggedInAppScopeFlowNode.kt

@@ -33,6 +33,7 @@ import io.element.android.libraries.architecture.createNode
 import io.element.android.libraries.architecture.inputs
 import io.element.android.libraries.di.DependencyInjectionGraphOwner
 import io.element.android.libraries.matrix.api.MatrixClient
+import io.element.android.libraries.matrix.api.core.SessionId
 import io.element.android.libraries.matrixmedia.api.ImageLoaderHolder
 import kotlinx.parcelize.Parcelize
 
@@ -59,6 +60,7 @@ class LoggedInAppScopeFlowNode(
     interface Callback : Plugin {
         fun navigateToBugReport()
         fun navigateToAddAccount()
+        fun navigateToSession(sessionId: SessionId)
     }
 
     private val callback: Callback = callback()
@@ -91,6 +93,10 @@ class LoggedInAppScopeFlowNode(
             override fun navigateToAddAccount() {
                 callback.navigateToAddAccount()
             }
+
+            override fun navigateToSession(sessionId: SessionId) {
+                callback.navigateToSession(sessionId)
+            }
         }
         return createNode<LoggedInFlowNode>(buildContext, listOf(callback))
     }

appnav/src/main/kotlin/io/element/android/appnav/LoggedInFlowNode.kt

@@ -85,6 +85,7 @@ import io.element.android.libraries.matrix.api.MatrixClient
 import io.element.android.libraries.matrix.api.core.EventId
 import io.element.android.libraries.matrix.api.core.RoomId
 import io.element.android.libraries.matrix.api.core.RoomIdOrAlias
+import io.element.android.libraries.matrix.api.core.SessionId
 import io.element.android.libraries.matrix.api.core.UserId
 import io.element.android.libraries.matrix.api.core.toRoomIdOrAlias
 import io.element.android.libraries.matrix.api.permalink.PermalinkData
@@ -169,6 +170,7 @@ class LoggedInFlowNode(
     interface Callback : Plugin {
         fun navigateToBugReport()
         fun navigateToAddAccount()
+        fun navigateToSession(sessionId: SessionId)
     }
 
     private val callback: Callback = callback()
@@ -356,6 +358,10 @@ class LoggedInFlowNode(
                     override fun navigateToAddAccount() {
                         callback.navigateToAddAccount()
                     }
+
+                    override fun navigateToSession(sessionId: SessionId) {
+                        callback.navigateToSession(sessionId)
+                    }
                 }
                 homeEntryPoint.createNode(
                     parentNode = this,
@@ -448,6 +454,10 @@ class LoggedInFlowNode(
                         callback.navigateToAddAccount()
                     }
 
+                    override fun navigateToSession(sessionId: SessionId) {
+                        callback.navigateToSession(sessionId)
+                    }
+
                     override fun navigateToLinkNewDevice() {
                         backstack.push(NavTarget.LinkNewDevice)
                     }

appnav/src/main/kotlin/io/element/android/appnav/RootFlowNode.kt

@@ -416,6 +416,12 @@ class RootFlowNode(
                     override fun navigateToAddAccount() {
                         backstack.push(NavTarget.NotLoggedInFlow(null))
                     }
+
+                    override fun navigateToSession(sessionId: SessionId) {
+                        lifecycleScope.launch {
+                            sessionStore.setLatestSession(sessionId.value)
+                        }
+                    }
                 }
                 val savedNavState = extractSavedStateForNavTarget(navTarget, this.buildContext.savedStateMap)
                 val buildContext = if (savedNavState != null) {

features/home/api/src/main/kotlin/io/element/android/features/home/api/HomeEntryPoint.kt

@@ -14,6 +14,7 @@ import com.bumble.appyx.core.plugin.Plugin
 import io.element.android.libraries.architecture.FeatureEntryPoint
 import io.element.android.libraries.matrix.api.core.EventId
 import io.element.android.libraries.matrix.api.core.RoomId
+import io.element.android.libraries.matrix.api.core.SessionId
 import io.element.android.libraries.matrix.api.room.JoinedRoom
 
 interface HomeEntryPoint : FeatureEntryPoint {
@@ -33,5 +34,6 @@ interface HomeEntryPoint : FeatureEntryPoint {
         fun navigateToRoomSettings(roomId: RoomId)
         fun navigateToBugReport()
         fun navigateToAddAccount()
+        fun navigateToSession(sessionId: SessionId)
     }
 }

features/home/impl/src/main/kotlin/io/element/android/features/home/impl/HomeEvent.kt

@@ -8,10 +8,7 @@
 
 package io.element.android.features.home.impl
 
-import io.element.android.libraries.matrix.api.core.SessionId
-
 sealed interface HomeEvent {
     data class SelectHomeNavigationBarItem(val item: HomeNavigationBarItem) : HomeEvent
-    data class SwitchToAccount(val sessionId: SessionId) : HomeEvent
     data object DismissMultiAccountAnnouncement : HomeEvent
 }

features/home/impl/src/main/kotlin/io/element/android/features/home/impl/HomeFlowNode.kt

@@ -222,6 +222,7 @@ class HomeFlowNode(
                 onRoomClick = ::navigateToRoom,
                 onSettingsClick = callback::navigateToSettings,
                 onAddAccountClick = callback::navigateToAddAccount,
+                onSwitchToAccount = callback::navigateToSession,
                 onStartChatClick = callback::navigateToCreateRoom,
                 onCreateSpaceClick = callback::navigateToCreateSpace,
                 onSetUpRecoveryClick = callback::navigateToSetUpRecovery,

features/home/impl/src/main/kotlin/io/element/android/features/home/impl/HomePresenter.kt

@@ -126,9 +126,6 @@ class HomePresenter(
                 is HomeEvent.SelectHomeNavigationBarItem -> {
                     currentHomeNavigationBarItemOrdinal = event.item.ordinal
                 }
-                is HomeEvent.SwitchToAccount -> coroutineState.launch {
-                    sessionStore.setLatestSession(event.sessionId.value)
-                }
                 HomeEvent.DismissMultiAccountAnnouncement -> coroutineState.launch {
                     announcementService.onAnnouncementDismissed(Announcement.MultiAccount)
                 }

features/home/impl/src/main/kotlin/io/element/android/features/home/impl/HomeView.kt

@@ -69,6 +69,7 @@ import io.element.android.libraries.designsystem.utils.snackbar.SnackbarHost
 import io.element.android.libraries.designsystem.utils.snackbar.rememberSnackbarHostState
 import io.element.android.libraries.matrix.api.core.EventId
 import io.element.android.libraries.matrix.api.core.RoomId
+import io.element.android.libraries.matrix.api.core.SessionId
 import io.element.android.libraries.ui.strings.CommonStrings
 import kotlinx.coroutines.launch
 
@@ -78,6 +79,7 @@ fun HomeView(
     onRoomClick: (RoomId, EventId?) -> Unit,
     onSettingsClick: () -> Unit,
     onAddAccountClick: () -> Unit,
+    onSwitchToAccount: (SessionId) -> Unit,
     onSetUpRecoveryClick: () -> Unit,
     onConfirmRecoveryKeyClick: () -> Unit,
     onStartChatClick: () -> Unit,
@@ -130,6 +132,7 @@ fun HomeView(
             onStartChatClick = { if (firstThrottler.canHandle()) onStartChatClick() },
             onCreateSpaceClick = { if (firstThrottler.canHandle()) onCreateSpaceClick() },
             onMenuActionClick = onMenuActionClick,
+            onSwitchToAccount = onSwitchToAccount,
         )
 
         if (state.globalSearchState.isEnabled) {
@@ -167,6 +170,7 @@ private fun HomeScaffold(
     onStartChatClick: () -> Unit,
     onCreateSpaceClick: () -> Unit,
     onMenuActionClick: (RoomListMenuAction) -> Unit,
+    onSwitchToAccount: (SessionId) -> Unit,
     modifier: Modifier = Modifier,
 ) {
     fun onRoomClick(room: RoomListRoomSummary) {
@@ -213,9 +217,7 @@ private fun HomeScaffold(
                 },
                 onMenuActionClick = onMenuActionClick,
                 onOpenSettings = onOpenSettings,
-                onAccountSwitch = {
+                onAccountSwitch = onSwitchToAccount,
-                    state.eventSink(HomeEvent.SwitchToAccount(it))
-                },
                 scrollBehavior = scrollBehavior,
                 displayFilters = state.displayRoomListFilters,
                 filtersState = roomListState.filtersState,
@@ -379,6 +381,7 @@ internal fun HomeViewPreview(@PreviewParameter(HomeStatePreviewParam::class) sta
         onRoomClick = { _, _ -> },
         onSettingsClick = {},
         onAddAccountClick = {},
+        onSwitchToAccount = {},
         onSetUpRecoveryClick = {},
         onConfirmRecoveryKeyClick = {},
         onStartChatClick = {},
@@ -400,6 +403,7 @@ internal fun HomeViewA11yPreview() = ElementPreview {
         onRoomClick = { _, _ -> },
         onSettingsClick = {},
         onAddAccountClick = {},
+        onSwitchToAccount = {},
         onSetUpRecoveryClick = {},
         onConfirmRecoveryKeyClick = {},
         onStartChatClick = {},

features/home/impl/src/test/kotlin/io/element/android/features/home/impl/DefaultHomeEntryPointTest.kt

@@ -14,6 +14,7 @@ import io.element.android.features.home.api.HomeEntryPoint
 import io.element.android.features.invite.test.declineandblock.FakeDeclineInviteAndBlockEntryPoint
 import io.element.android.libraries.matrix.api.core.EventId
 import io.element.android.libraries.matrix.api.core.RoomId
+import io.element.android.libraries.matrix.api.core.SessionId
 import io.element.android.libraries.matrix.api.room.JoinedRoom
 import io.element.android.libraries.matrix.test.FakeMatrixClient
 import io.element.android.services.analytics.test.FakeAnalyticsService
@@ -53,6 +54,7 @@ class DefaultHomeEntryPointTest : RobolectricTest() {
             override fun navigateToRoomSettings(roomId: RoomId) = lambdaError()
             override fun navigateToBugReport() = lambdaError()
             override fun navigateToAddAccount() = lambdaError()
+            override fun navigateToSession(sessionId: SessionId) = lambdaError()
         }
         val result = entryPoint.createNode(
             parentNode = parentNode,

features/home/impl/src/test/kotlin/io/element/android/features/home/impl/roomlist/RoomListViewTest.kt

@@ -305,6 +305,7 @@ private fun AndroidComposeUiTest<ComponentActivity>.setRoomListView(
             onRoomClick = { roomId, _ -> onRoomClick(roomId) },
             onSettingsClick = onSettingsClick,
             onAddAccountClick = onAddAccountClick,
+            onSwitchToAccount = EnsureNeverCalledWithParam(),
             onSetUpRecoveryClick = onSetUpRecoveryClick,
             onConfirmRecoveryKeyClick = onConfirmRecoveryKeyClick,
             onStartChatClick = onCreateRoomClick,

features/preferences/api/src/main/kotlin/io/element/android/features/preferences/api/PreferencesEntryPoint.kt

@@ -16,6 +16,7 @@ import io.element.android.libraries.architecture.FeatureEntryPoint
 import io.element.android.libraries.architecture.NodeInputs
 import io.element.android.libraries.matrix.api.core.EventId
 import io.element.android.libraries.matrix.api.core.RoomId
+import io.element.android.libraries.matrix.api.core.SessionId
 import kotlinx.parcelize.Parcelize
 
 interface PreferencesEntryPoint : FeatureEntryPoint {
@@ -44,6 +45,7 @@ interface PreferencesEntryPoint : FeatureEntryPoint {
 
     interface Callback : Plugin {
         fun navigateToAddAccount()
+        fun navigateToSession(sessionId: SessionId)
         fun navigateToLinkNewDevice()
         fun navigateToBugReport()
         fun navigateToSecureBackup()

features/preferences/impl/src/main/kotlin/io/element/android/features/preferences/impl/PreferencesFlowNode.kt

@@ -46,6 +46,7 @@ import io.element.android.libraries.core.mimetype.MimeTypes
 import io.element.android.libraries.di.SessionScope
 import io.element.android.libraries.matrix.api.core.EventId
 import io.element.android.libraries.matrix.api.core.RoomId
+import io.element.android.libraries.matrix.api.core.SessionId
 import io.element.android.libraries.matrix.api.user.MatrixUser
 import io.element.android.libraries.mediaviewer.api.FileViewerEntryPoint
 import io.element.android.libraries.troubleshoot.api.NotificationTroubleShootEntryPoint
@@ -141,6 +142,10 @@ class PreferencesFlowNode(
                         callback.navigateToAddAccount()
                     }
 
+                    override fun navigateToSession(sessionId: SessionId) {
+                        callback.navigateToSession(sessionId)
+                    }
+
                     override fun navigateToAnalyticsSettings() {
                         backstack.push(NavTarget.AnalyticsSettings)
                     }

features/preferences/impl/src/main/kotlin/io/element/android/features/preferences/impl/root/PreferencesRootEvent.kt

@@ -8,11 +8,8 @@
 
 package io.element.android.features.preferences.impl.root
 
-import io.element.android.libraries.matrix.api.core.SessionId
-
 sealed interface PreferencesRootEvent {
     data object OnVersionInfoClick : PreferencesRootEvent
-    data class SwitchToSession(val sessionId: SessionId) : PreferencesRootEvent
     data object ToggleOtherAccountsExpanded : PreferencesRootEvent
     data class SetTheme(val theme: ThemeOption) : PreferencesRootEvent
 }

features/preferences/impl/src/main/kotlin/io/element/android/features/preferences/impl/root/PreferencesRootNode.kt

@@ -24,6 +24,7 @@ import io.element.android.libraries.androidutils.browser.openUrlInChromeCustomTa
 import io.element.android.libraries.architecture.callback
 import io.element.android.libraries.di.SessionScope
 import io.element.android.libraries.emoji.api.picker.EmojiPickerRenderer
+import io.element.android.libraries.matrix.api.core.SessionId
 
 @ContributesNode(SessionScope::class)
 @AssistedInject
@@ -35,6 +36,7 @@ class PreferencesRootNode(
 ) : Node(buildContext, plugins = plugins) {
     interface Callback : PreferencesAccountCallback, Plugin {
         fun navigateToAddAccount()
+        fun navigateToSession(sessionId: SessionId)
         fun navigateToAnalyticsSettings()
         fun navigateToAbout()
         fun navigateToDeveloperSettings()
@@ -72,6 +74,7 @@ class PreferencesRootNode(
             modifier = modifier,
             onBackClick = this::navigateUp,
             onAddAccountClick = callback::navigateToAddAccount,
+            onSwitchToSession = callback::navigateToSession,
             onOpenAnalytics = callback::navigateToAnalyticsSettings,
             onOpenAbout = callback::navigateToAbout,
             onOpenDeveloperSettings = callback::navigateToDeveloperSettings,

features/preferences/impl/src/main/kotlin/io/element/android/features/preferences/impl/root/PreferencesRootPresenter.kt

@@ -124,9 +124,6 @@ class PreferencesRootPresenter(
                 is PreferencesRootEvent.OnVersionInfoClick -> {
                     showDeveloperSettingsProvider.unlockDeveloperSettings(coroutineScope)
                 }
-                is PreferencesRootEvent.SwitchToSession -> coroutineScope.launch {
-                    sessionStore.setLatestSession(event.sessionId.value)
-                }
                 PreferencesRootEvent.ToggleOtherAccountsExpanded -> coroutineScope.launch {
                     appPreferencesStore.setOtherAccountsExpanded(!isOtherAccountsSectionExpanded)
                 }

features/preferences/impl/src/main/kotlin/io/element/android/features/preferences/impl/root/PreferencesRootView.kt

@@ -65,6 +65,7 @@ import io.element.android.libraries.designsystem.utils.snackbar.SnackbarHost
 import io.element.android.libraries.designsystem.utils.snackbar.rememberSnackbarHostState
 import io.element.android.libraries.emoji.api.picker.EmojiPickerRenderer
 import io.element.android.libraries.emoji.api.picker.NoOpEmojiPickerRenderer
+import io.element.android.libraries.matrix.api.core.SessionId
 import io.element.android.libraries.matrix.api.user.MatrixUser
 import io.element.android.libraries.matrix.ui.components.MatrixUserRow
 import io.element.android.libraries.matrix.ui.model.getAvatarData
@@ -79,6 +80,7 @@ fun PreferencesRootView(
     emojiPickerRenderer: EmojiPickerRenderer,
     onBackClick: () -> Unit,
     onAddAccountClick: () -> Unit,
+    onSwitchToSession: (SessionId) -> Unit,
     onOpenAnalytics: () -> Unit,
     onOpenLockScreenSettings: () -> Unit,
     onOpenAbout: () -> Unit,
@@ -124,6 +126,7 @@ fun PreferencesRootView(
                 MultiAccountSection(
                     state = state,
                     onAddAccountClick = onAddAccountClick,
+                    onSwitchToSession = onSwitchToSession,
                 )
             }
             HorizontalDivider(
@@ -208,6 +211,7 @@ private fun ColumnScope.UserStatusSection(
 private fun ColumnScope.MultiAccountSection(
     state: PreferencesRootState,
     onAddAccountClick: () -> Unit,
+    onSwitchToSession: (SessionId) -> Unit,
 ) {
     HorizontalDivider(
         thickness = 8.dp,
@@ -275,7 +279,7 @@ private fun ColumnScope.MultiAccountSection(
                     MatrixUserRow(
                         modifier = Modifier
                             .clickable {
-                                state.eventSink(PreferencesRootEvent.SwitchToSession(matrixUser.userId))
+                                onSwitchToSession(matrixUser.userId)
                             }
                             .padding(top = 2.dp, bottom = 2.dp, end = 8.dp),
                         matrixUser = matrixUser,
@@ -427,6 +431,7 @@ private fun ContentToPreview(state: PreferencesRootState) {
         emojiPickerRenderer = NoOpEmojiPickerRenderer,
         onBackClick = {},
         onAddAccountClick = {},
+        onSwitchToSession = {},
         onOpenAnalytics = {},
         onOpenDeveloperSettings = {},
         onOpenLocationSettings = {},

features/preferences/impl/src/test/kotlin/io/element/android/features/preferences/impl/DefaultPreferencesEntryPointTest.kt

@@ -19,6 +19,7 @@ import io.element.android.features.logout.test.FakeLogoutEntryPoint
 import io.element.android.features.preferences.api.PreferencesEntryPoint
 import io.element.android.libraries.matrix.api.core.EventId
 import io.element.android.libraries.matrix.api.core.RoomId
+import io.element.android.libraries.matrix.api.core.SessionId
 import io.element.android.libraries.mediaviewer.test.FakeFileViewerEntryPoint
 import io.element.android.libraries.troubleshoot.test.FakeNotificationTroubleShootEntryPoint
 import io.element.android.libraries.troubleshoot.test.FakePushHistoryEntryPoint
@@ -52,6 +53,7 @@ class DefaultPreferencesEntryPointTest {
         }
         val callback = object : PreferencesEntryPoint.Callback {
             override fun navigateToAddAccount() = lambdaError()
+            override fun navigateToSession(sessionId: SessionId) = lambdaError()
             override fun navigateToLinkNewDevice() = lambdaError()
             override fun navigateToBugReport() = lambdaError()
             override fun navigateToSecureBackup() = lambdaError()

features/preferences/impl/src/test/kotlin/io/element/android/features/preferences/impl/root/PreferencesRootPresenterTest.kt

@@ -39,8 +39,6 @@ import io.element.android.libraries.sessionstorage.test.aSessionData
 import io.element.android.services.analytics.test.FakeAnalyticsService
 import io.element.android.tests.testutils.WarmUpRule
 import io.element.android.tests.testutils.consumeItemsUntilPredicate
-import io.element.android.tests.testutils.lambda.lambdaRecorder
-import io.element.android.tests.testutils.lambda.value
 import io.element.android.tests.testutils.test
 import kotlinx.collections.immutable.toImmutableList
 import kotlinx.coroutines.CoroutineScope
@@ -179,24 +177,6 @@ class PreferencesRootPresenterTest {
         }
     }
 
-    @Test
-    fun `present - switch session invoke method on the session store`() = runTest {
-        val setLatestSessionResult = lambdaRecorder<String, Unit> { }
-        val sessionStore = InMemorySessionStore(
-            initialList = listOf(
-                aSessionData(sessionId = A_SESSION_ID.value),
-                aSessionData(sessionId = A_SESSION_ID_2.value),
-            ),
-            setLatestSessionResult = setLatestSessionResult,
-        )
-        createPreferencesRootPresenter(sessionStore = sessionStore).test {
-            val loadedState = awaitFirstItem()
-            loadedState.eventSink(PreferencesRootEvent.SwitchToSession(A_SESSION_ID_2))
-            setLatestSessionResult.assertions().isCalledOnce()
-                .with(value(A_SESSION_ID_2.value))
-        }
-    }
-
     @Test
     fun `present - labs can be shown if any feature flag is in labs and not finished`() = runTest {
         createPreferencesRootPresenter(

features/preferences/impl/src/test/kotlin/io/element/android/features/preferences/impl/root/PreferencesRootViewTest.kt

@@ -20,6 +20,7 @@ import androidx.compose.ui.test.performScrollTo
 import androidx.compose.ui.test.v2.runAndroidComposeUiTest
 import io.element.android.features.preferences.impl.R
 import io.element.android.libraries.emoji.api.picker.NoOpEmojiPickerRenderer
+import io.element.android.libraries.matrix.api.core.SessionId
 import io.element.android.libraries.matrix.api.user.MatrixUser
 import io.element.android.libraries.matrix.test.A_USER_ID_2
 import io.element.android.libraries.matrix.ui.components.aMatrixUser
@@ -69,23 +70,25 @@ class PreferencesRootViewTest : RobolectricTest() {
     }
 
     @Test
-    fun `clicking on other session sends a SwitchToSession`() = runAndroidComposeUiTest {
+    fun `clicking on other session invokes the expected callback`() = runAndroidComposeUiTest {
-        val eventsRecorder = EventsRecorder<PreferencesRootEvent>()
+        val eventsRecorder = EventsRecorder<PreferencesRootEvent>(expectEvents = false)
-        setView(
+        ensureCalledOnceWithParam(A_USER_ID_2) { callback ->
-            aPreferencesRootState(
+            setView(
-                isMultiAccountEnabled = true,
+                aPreferencesRootState(
-                isOtherAccountsSectionExpanded = true,
+                    isMultiAccountEnabled = true,
-                otherSessions = listOf(
+                    isOtherAccountsSectionExpanded = true,
-                    aMatrixUser(
+                    otherSessions = listOf(
-                        id = A_USER_ID_2.value,
+                        aMatrixUser(
-                        displayName = "Bob",
+                            id = A_USER_ID_2.value,
-                    )
+                            displayName = "Bob",
+                        )
+                    ),
+                    eventSink = eventsRecorder,
                 ),
-                eventSink = eventsRecorder,
+                onSwitchToSession = callback,
-            ),
+            )
-        )
+            onNodeWithText("Bob").performClick()
-        onNodeWithText("Bob").performClick()
+        }
-        eventsRecorder.assertSingle(PreferencesRootEvent.SwitchToSession(A_USER_ID_2))
     }
 
     @Test
@@ -395,6 +398,7 @@ private fun AndroidComposeUiTest<ComponentActivity>.setView(
     state: PreferencesRootState,
     onBackClick: () -> Unit = EnsureNeverCalled(),
     onAddAccountClick: () -> Unit = EnsureNeverCalled(),
+    onSwitchToSession: (SessionId) -> Unit = EnsureNeverCalledWithParam(),
     onOpenAnalytics: () -> Unit = EnsureNeverCalled(),
     onOpenLockScreenSettings: () -> Unit = EnsureNeverCalled(),
     onOpenAbout: () -> Unit = EnsureNeverCalled(),
@@ -418,6 +422,7 @@ private fun AndroidComposeUiTest<ComponentActivity>.setView(
             emojiPickerRenderer = NoOpEmojiPickerRenderer,
             onBackClick = onBackClick,
             onAddAccountClick = onAddAccountClick,
+            onSwitchToSession = onSwitchToSession,
             onOpenAnalytics = onOpenAnalytics,
             onOpenLockScreenSettings = onOpenLockScreenSettings,
             onOpenAbout = onOpenAbout,