Merge pull request #6877 from vector-im/feature/eric/new-layout-navigation

Space Switching Back Navigation

changelog.d/6871.feature

@@ -0,0 +1 @@
+Improves Developer Mode Debug Button UX and adds it to New App Layout

changelog.d/6877.wip

@@ -0,0 +1 @@
+[New Layout] Adds back navigation through spaces

vector/src/main/java/im/vector/app/SpaceStateHandler.kt

@@ -51,11 +51,13 @@ interface SpaceStateHandler : DefaultLifecycleObserver {
     )
 
     /**
-     * Gets the current backstack of spaces (via their id).
+     * Gets the Space ID of the space on top of the backstack.
      *
-     * null may be an entry in the ArrayDeque to indicate the root space (All Chats)
+     * May return null to indicate the All Chats space.
      */
-    fun getSpaceBackstack(): ArrayDeque<String?>
+    fun popSpaceBackstack(): String?
+
+    fun getSpaceBackstack(): List<String?>
 
     /**
      * Gets a flow of the selected space for clients to react immediately to space changes.

vector/src/main/java/im/vector/app/SpaceStateHandlerImpl.kt

@@ -23,6 +23,7 @@ import im.vector.app.core.utils.BehaviorDataSource
 import im.vector.app.features.analytics.AnalyticsTracker
 import im.vector.app.features.analytics.plan.UserProperties
 import im.vector.app.features.session.coroutineScope
+import im.vector.app.features.settings.VectorPreferences
 import im.vector.app.features.ui.UiStateRepository
 import kotlinx.coroutines.CoroutineScope
 import kotlinx.coroutines.Dispatchers
@@ -52,13 +53,13 @@ class SpaceStateHandlerImpl @Inject constructor(
         private val sessionDataSource: ActiveSessionDataSource,
         private val uiStateRepository: UiStateRepository,
         private val activeSessionHolder: ActiveSessionHolder,
-        private val analyticsTracker: AnalyticsTracker
+        private val analyticsTracker: AnalyticsTracker,
+        private val vectorPreferences: VectorPreferences,
 ) : SpaceStateHandler {
 
     private val coroutineScope = CoroutineScope(SupervisorJob() + Dispatchers.Main)
     private val selectedSpaceDataSource = BehaviorDataSource<Option<RoomSummary>>(Option.empty())
     private val selectedSpaceFlow = selectedSpaceDataSource.stream()
-    private val spaceBackstack = ArrayDeque<String?>()
 
     override fun getCurrentSpace(): RoomSummary? {
         return selectedSpaceDataSource.currentValue?.orNull()?.let { spaceSummary ->
@@ -73,26 +74,26 @@ class SpaceStateHandlerImpl @Inject constructor(
             isForwardNavigation: Boolean,
     ) {
         val activeSession = session ?: activeSessionHolder.getSafeActiveSession() ?: return
-        val currentSpace = selectedSpaceDataSource.currentValue?.orNull()
+        val spaceToLeave = selectedSpaceDataSource.currentValue?.orNull()
-        val spaceSummary = spaceId?.let { activeSession.getRoomSummary(spaceId) }
+        val spaceToSet = spaceId?.let { activeSession.getRoomSummary(spaceId) }
-        val sameSpaceSelected = currentSpace != null && spaceId == currentSpace.roomId
+        val sameSpaceSelected = spaceId == spaceToLeave?.roomId
 
         if (sameSpaceSelected) {
             return
         }
 
         if (isForwardNavigation) {
-            spaceBackstack.addLast(currentSpace?.roomId)
+            addToBackstack(spaceToLeave, spaceToSet)
         }
 
         if (persistNow) {
-            uiStateRepository.storeSelectedSpace(spaceSummary?.roomId, activeSession.sessionId)
+            uiStateRepository.storeSelectedSpace(spaceToSet?.roomId, activeSession.sessionId)
         }
 
-        if (spaceSummary == null) {
+        if (spaceToSet == null) {
             selectedSpaceDataSource.post(Option.empty())
         } else {
-            selectedSpaceDataSource.post(Option.just(spaceSummary))
+            selectedSpaceDataSource.post(Option.just(spaceToSet))
         }
 
         if (spaceId != null) {
@@ -104,6 +105,17 @@ class SpaceStateHandlerImpl @Inject constructor(
         }
     }
 
+    private fun addToBackstack(spaceToLeave: RoomSummary?, spaceToSet: RoomSummary?) {
+        // Only add to the backstack if the space to set is not All Chats, else clear the backstack
+        if (spaceToSet != null) {
+            val currentPersistedBackstack = vectorPreferences.getSpaceBackstack().toMutableList()
+            currentPersistedBackstack.add(spaceToLeave?.roomId)
+            vectorPreferences.setSpaceBackstack(currentPersistedBackstack)
+        } else {
+            vectorPreferences.setSpaceBackstack(emptyList())
+        }
+    }
+
     private fun observeActiveSession() {
         sessionDataSource.stream()
                 .distinctUntilChanged()
@@ -127,7 +139,15 @@ class SpaceStateHandlerImpl @Inject constructor(
                 }.launchIn(session.coroutineScope)
     }
 
-    override fun getSpaceBackstack() = spaceBackstack
+    override fun popSpaceBackstack(): String? {
+        vectorPreferences.getSpaceBackstack().toMutableList().apply {
+            val poppedSpaceId = removeLast()
+            vectorPreferences.setSpaceBackstack(this)
+            return poppedSpaceId
+        }
+    }
+
+    override fun getSpaceBackstack() = vectorPreferences.getSpaceBackstack()
 
     override fun getSelectedSpaceFlow() = selectedSpaceFlow
 

vector/src/main/java/im/vector/app/features/home/HomeActivity.kt

@@ -41,6 +41,7 @@ import im.vector.app.core.di.ActiveSessionHolder
 import im.vector.app.core.extensions.hideKeyboard
 import im.vector.app.core.extensions.registerStartForActivityResult
 import im.vector.app.core.extensions.replaceFragment
+import im.vector.app.core.extensions.restart
 import im.vector.app.core.extensions.validateBackPressed
 import im.vector.app.core.platform.VectorBaseActivity
 import im.vector.app.core.platform.VectorMenuProvider
@@ -56,6 +57,8 @@ import im.vector.app.features.analytics.plan.MobileScreen
 import im.vector.app.features.analytics.plan.ViewRoom
 import im.vector.app.features.crypto.recover.SetupMode
 import im.vector.app.features.disclaimer.showDisclaimerDialog
+import im.vector.app.features.home.room.list.actions.RoomListSharedAction
+import im.vector.app.features.home.room.list.actions.RoomListSharedActionViewModel
 import im.vector.app.features.home.room.list.home.layout.HomeLayoutSettingBottomDialogFragment
 import im.vector.app.features.matrixto.MatrixToBottomSheet
 import im.vector.app.features.matrixto.OriginOfMatrixTo
@@ -110,6 +113,7 @@ class HomeActivity :
         VectorMenuProvider {
 
     private lateinit var sharedActionViewModel: HomeSharedActionViewModel
+    private lateinit var roomListSharedActionViewModel: RoomListSharedActionViewModel
 
     private val homeActivityViewModel: HomeActivityViewModel by viewModel()
 
@@ -136,6 +140,8 @@ class HomeActivity :
     @Inject lateinit var fcmHelper: FcmHelper
     @Inject lateinit var nightlyProxy: NightlyProxy
 
+    private var isNewAppLayoutEnabled: Boolean = false // delete once old app layout is removed
+
     private val createSpaceResultLauncher = registerStartForActivityResult { activityResult ->
         if (activityResult.resultCode == Activity.RESULT_OK) {
             val spaceId = SpaceCreationActivity.getCreatedSpaceId(activityResult.data)
@@ -155,8 +161,9 @@ class HomeActivity :
                 navigator.switchToSpace(
                         context = this,
                         spaceId = spaceId,
-                        postSwitchOption
+                        postSwitchOption,
                 )
+                roomListSharedActionViewModel.post(RoomListSharedAction.CloseBottomSheet)
             }
         }
     }
@@ -193,6 +200,7 @@ class HomeActivity :
 
     override fun onCreate(savedInstanceState: Bundle?) {
         super.onCreate(savedInstanceState)
+        isNewAppLayoutEnabled = vectorFeatures.isNewAppLayoutEnabled()
         analyticsScreenName = MobileScreen.ScreenName.Home
         supportFragmentManager.registerFragmentLifecycleCallbacks(fragmentLifecycleCallbacks, false)
         unifiedPushHelper.register(this) {
@@ -205,6 +213,7 @@ class HomeActivity :
             }
         }
         sharedActionViewModel = viewModelProvider[HomeSharedActionViewModel::class.java]
+        roomListSharedActionViewModel = viewModelProvider[RoomListSharedActionViewModel::class.java]
         views.drawerLayout.addDrawerListener(drawerListener)
         if (isFirstCreation()) {
             if (vectorFeatures.isNewAppLayoutEnabled()) {
@@ -561,6 +570,14 @@ class HomeActivity :
 
         // Check nightly
         nightlyProxy.onHomeResumed()
+
+        checkNewAppLayoutFlagChange()
+    }
+
+    private fun checkNewAppLayoutFlagChange() {
+        if (buildMeta.isDebug && vectorFeatures.isNewAppLayoutEnabled() != isNewAppLayoutEnabled) {
+            restart()
+        }
     }
 
     override fun getMenuRes() = if (vectorFeatures.isNewAppLayoutEnabled()) R.menu.menu_new_home else R.menu.menu_home

vector/src/main/java/im/vector/app/features/home/HomeDetailFragment.kt

@@ -186,7 +186,7 @@ class HomeDetailFragment :
     }
 
     private fun navigateBack() {
-        val previousSpaceId = spaceStateHandler.getSpaceBackstack().removeLastOrNull()
+        val previousSpaceId = spaceStateHandler.popSpaceBackstack()
         val parentSpaceId = spaceStateHandler.getCurrentSpace()?.flattenParentIds?.lastOrNull()
         setCurrentSpace(previousSpaceId ?: parentSpaceId)
     }

vector/src/main/java/im/vector/app/features/home/HomeDrawerFragment.kt

@@ -116,10 +116,14 @@ class HomeDrawerFragment :
         }
 
         // Debug menu
-        views.homeDrawerHeaderDebugView.isVisible = buildMeta.isDebug && vectorPreferences.developerMode()
         views.homeDrawerHeaderDebugView.debouncedClicks {
             sharedActionViewModel.post(HomeActivitySharedAction.CloseDrawer)
             navigator.openDebug(requireActivity())
         }
     }
+
+    override fun onResume() {
+        super.onResume()
+        views.homeDrawerHeaderDebugView.isVisible = buildMeta.isDebug && vectorPreferences.developerMode()
+    }
 }

vector/src/main/java/im/vector/app/features/home/NewHomeDetailFragment.kt

@@ -23,10 +23,12 @@ import android.view.Menu
 import android.view.MenuItem
 import android.view.View
 import android.view.ViewGroup
+import androidx.core.view.isVisible
 import androidx.lifecycle.lifecycleScope
 import com.airbnb.mvrx.activityViewModel
 import com.airbnb.mvrx.fragmentViewModel
 import com.airbnb.mvrx.withState
+import com.google.android.material.appbar.AppBarLayout
 import dagger.hilt.android.AndroidEntryPoint
 import im.vector.app.R
 import im.vector.app.SpaceStateHandler
@@ -35,6 +37,7 @@ import im.vector.app.core.platform.OnBackPressed
 import im.vector.app.core.platform.VectorBaseActivity
 import im.vector.app.core.platform.VectorBaseFragment
 import im.vector.app.core.platform.VectorMenuProvider
+import im.vector.app.core.resources.BuildMeta
 import im.vector.app.core.resources.ColorProvider
 import im.vector.app.core.ui.views.CurrentCallsView
 import im.vector.app.core.ui.views.CurrentCallsViewPresenter
@@ -74,6 +77,7 @@ class NewHomeDetailFragment :
     @Inject lateinit var vectorPreferences: VectorPreferences
     @Inject lateinit var spaceStateHandler: SpaceStateHandler
     @Inject lateinit var session: Session
+    @Inject lateinit var buildMeta: BuildMeta
 
     private val viewModel: HomeDetailViewModel by fragmentViewModel()
     private val unknownDeviceDetectorSharedViewModel: UnknownDeviceDetectorSharedViewModel by activityViewModel()
@@ -127,6 +131,7 @@ class NewHomeDetailFragment :
         setupToolbar()
         setupKeysBackupBanner()
         setupActiveCallView()
+        setupDebugButton()
 
         childFragmentManager.commitTransaction {
             add(R.id.roomListContainer, HomeRoomListFragment::class.java, null, HOME_ROOM_LIST_FRAGMENT_TAG)
@@ -169,12 +174,6 @@ class NewHomeDetailFragment :
                 }
     }
 
-    private fun navigateBack() {
-        val previousSpaceId = spaceStateHandler.getSpaceBackstack().removeLastOrNull()
-        val parentSpaceId = spaceStateHandler.getCurrentSpace()?.flattenParentIds?.lastOrNull()
-        setCurrentSpace(previousSpaceId ?: parentSpaceId)
-    }
-
     private fun setCurrentSpace(spaceId: String?) {
         spaceStateHandler.setCurrentSpace(spaceId, isForwardNavigation = false)
         sharedActionViewModel.post(HomeActivitySharedAction.OnCloseSpace)
@@ -189,6 +188,7 @@ class NewHomeDetailFragment :
         super.onResume()
         callManager.checkForProtocolsSupportIfNeeded()
         refreshSpaceState()
+        refreshDebugButtonState()
     }
 
     private fun refreshSpaceState() {
@@ -298,6 +298,21 @@ class NewHomeDetailFragment :
         }
     }
 
+    private fun setupDebugButton() {
+        views.debugButton.debouncedClicks {
+            sharedActionViewModel.post(HomeActivitySharedAction.CloseDrawer)
+            navigator.openDebug(requireActivity())
+        }
+
+        views.appBarLayout.addOnOffsetChangedListener(AppBarLayout.OnOffsetChangedListener { _, verticalOffset ->
+            views.debugButton.isVisible = verticalOffset == 0
+        })
+    }
+
+    private fun refreshDebugButtonState() {
+        views.debugButton.isVisible = buildMeta.isDebug && vectorPreferences.developerMode()
+    }
+
     /* ==========================================================================================
      * KeysBackupBanner Listener
      * ========================================================================================== */
@@ -337,13 +352,16 @@ class NewHomeDetailFragment :
         }
     }
 
-    override fun onBackPressed(toolbarButton: Boolean) = if (spaceStateHandler.getCurrentSpace() != null) {
+    override fun onBackPressed(toolbarButton: Boolean) = if (spaceStateHandler.isRoot()) {
-        navigateBack()
-        true
-    } else {
         false
+    } else {
+        val lastSpace = spaceStateHandler.popSpaceBackstack()
+        spaceStateHandler.setCurrentSpace(lastSpace, isForwardNavigation = false)
+        true
     }
 
+    private fun SpaceStateHandler.isRoot() = getSpaceBackstack().isEmpty()
+
     companion object {
         private const val HOME_ROOM_LIST_FRAGMENT_TAG = "TAG_HOME_ROOM_LIST"
     }

vector/src/main/java/im/vector/app/features/navigation/DefaultNavigator.kt

@@ -176,13 +176,25 @@ class DefaultNavigator @Inject constructor(
         startActivity(context, intent, buildTask)
     }
 
-    override fun switchToSpace(context: Context, spaceId: String, postSwitchSpaceAction: Navigator.PostSwitchSpaceAction) {
+    override fun switchToSpace(
+            context: Context,
+            spaceId: String,
+            postSwitchSpaceAction: Navigator.PostSwitchSpaceAction,
+    ) {
         if (sessionHolder.getSafeActiveSession()?.getRoomSummary(spaceId) == null) {
             fatalError("Trying to open an unknown space $spaceId", vectorPreferences.failFast())
             return
         }
         spaceStateHandler.setCurrentSpace(spaceId)
-        when (postSwitchSpaceAction) {
+        handlePostSwitchAction(context, spaceId, postSwitchSpaceAction)
+    }
+
+    private fun handlePostSwitchAction(
+            context: Context,
+            spaceId: String,
+            action: Navigator.PostSwitchSpaceAction,
+    ) {
+        when (action) {
             Navigator.PostSwitchSpaceAction.None -> {
                 // go back to home if we are showing room details?
                 // This is a bit ugly, but the navigator is supposed to know about the activity stack
@@ -198,9 +210,9 @@ class DefaultNavigator @Inject constructor(
             }
             is Navigator.PostSwitchSpaceAction.OpenDefaultRoom -> {
                 val args = TimelineArgs(
-                        postSwitchSpaceAction.roomId,
+                        action.roomId,
                         eventId = null,
-                        openShareSpaceForId = spaceId.takeIf { postSwitchSpaceAction.showShareSheet }
+                        openShareSpaceForId = spaceId.takeIf { action.showShareSheet }
                 )
                 val intent = RoomDetailActivity.newIntent(context, args, false)
                 startActivity(context, intent, false)

vector/src/main/java/im/vector/app/features/navigation/Navigator.kt

@@ -68,7 +68,11 @@ interface Navigator {
         data class OpenDefaultRoom(val roomId: String, val showShareSheet: Boolean) : PostSwitchSpaceAction()
     }
 
-    fun switchToSpace(context: Context, spaceId: String, postSwitchSpaceAction: PostSwitchSpaceAction)
+    fun switchToSpace(
+            context: Context,
+            spaceId: String,
+            postSwitchSpaceAction: PostSwitchSpaceAction,
+    )
 
     fun openSpacePreview(context: Context, spaceId: String)
 

vector/src/main/java/im/vector/app/features/settings/VectorPreferences.kt

@@ -78,6 +78,7 @@ class VectorPreferences @Inject constructor(
         const val SETTINGS_ALLOW_INTEGRATIONS_KEY = "SETTINGS_ALLOW_INTEGRATIONS_KEY"
         const val SETTINGS_INTEGRATION_MANAGER_UI_URL_KEY = "SETTINGS_INTEGRATION_MANAGER_UI_URL_KEY"
         const val SETTINGS_SECURE_MESSAGE_RECOVERY_PREFERENCE_KEY = "SETTINGS_SECURE_MESSAGE_RECOVERY_PREFERENCE_KEY"
+        const val SETTINGS_PERSISTED_SPACE_BACKSTACK = "SETTINGS_PERSISTED_SPACE_BACKSTACK"
 
         const val SETTINGS_CRYPTOGRAPHY_HS_ADMIN_DISABLED_E2E_DEFAULT = "SETTINGS_CRYPTOGRAPHY_HS_ADMIN_DISABLED_E2E_DEFAULT"
 //        const val SETTINGS_SECURE_BACKUP_RESET_PREFERENCE_KEY = "SETTINGS_SECURE_BACKUP_RESET_PREFERENCE_KEY"
@@ -1126,6 +1127,25 @@ class VectorPreferences @Inject constructor(
                 .apply()
     }
 
+    /**
+     * Sets the space backstack that is used for up navigation.
+     * This needs to be persisted because navigating up through spaces should work across sessions.
+     *
+     * Only the IDs of the spaces are stored.
+     */
+    fun setSpaceBackstack(spaceBackstack: List<String?>) {
+        val spaceIdsJoined = spaceBackstack.takeIf { it.isNotEmpty() }?.joinToString(",")
+        defaultPrefs.edit().putString(SETTINGS_PERSISTED_SPACE_BACKSTACK, spaceIdsJoined).apply()
+    }
+
+    /**
+     * Gets the space backstack used for up navigation.
+     */
+    fun getSpaceBackstack(): List<String?> {
+        val spaceIdsJoined = defaultPrefs.getString(SETTINGS_PERSISTED_SPACE_BACKSTACK, null)
+        return spaceIdsJoined?.takeIf { it.isNotEmpty() }?.split(",").orEmpty()
+    }
+
     fun showLiveSenderInfo(): Boolean {
         return defaultPrefs.getBoolean(SETTINGS_TIMELINE_SHOW_LIVE_SENDER_INFO, getDefault(R.bool.settings_timeline_show_live_sender_info_default))
     }

vector/src/main/java/im/vector/app/features/spaces/NewSpaceSummaryController.kt

@@ -63,10 +63,6 @@ class NewSpaceSummaryController @Inject constructor(
             homeCount: RoomAggregateNotificationCount,
             expandedStates: Map<String, Boolean>,
     ) {
-        newSpaceListHeaderItem {
-            id("space_list_header")
-        }
-
         addHomeItem(selectedSpace == null, homeCount)
         addSpaces(spaceSummaries, selectedSpace, rootSpaces, expandedStates)
         addCreateItem()

vector/src/main/java/im/vector/app/features/spaces/SpaceListViewModel.kt

@@ -65,7 +65,7 @@ class SpaceListViewModel @AssistedInject constructor(
         private val session: Session,
         private val vectorPreferences: VectorPreferences,
         private val autoAcceptInvites: AutoAcceptInvites,
-        private val analyticsTracker: AnalyticsTracker
+        private val analyticsTracker: AnalyticsTracker,
 ) : VectorViewModel<SpaceListViewState, SpaceListAction, SpaceListViewEvents>(initialState) {
 
     @AssistedFactory
@@ -88,9 +88,7 @@ class SpaceListViewModel @AssistedInject constructor(
         spaceStateHandler.getSelectedSpaceFlow()
                 .distinctUntilChanged()
                 .setOnEach { selectedSpaceOption ->
-                    copy(
+                    copy(selectedSpace = selectedSpaceOption.orNull())
-                            selectedSpace = selectedSpaceOption.orNull()
-                    )
                 }
 
         // XXX there should be a way to refactor this and share it

vector/src/main/res/layout/fragment_new_home_detail.xml

@@ -74,6 +74,19 @@
 
                 </com.google.android.material.appbar.MaterialToolbar>
 
+                <ImageView
+                    android:id="@+id/debug_button"
+                    style="@style/VectorDebug"
+                    android:layout_width="48dp"
+                    android:layout_height="48dp"
+                    android:layout_gravity="bottom|end"
+                    android:layout_marginStart="12dp"
+                    android:importantForAccessibility="no"
+                    android:scaleType="center"
+                    android:src="@drawable/ic_settings_x"
+                    app:tint="?colorPrimary"
+                    tools:ignore="MissingPrefix" />
+
             </com.google.android.material.appbar.CollapsingToolbarLayout>
 
         </com.google.android.material.appbar.AppBarLayout>

vector/src/main/res/layout/item_new_space_list_header.xml

@@ -1,16 +0,0 @@
-<?xml version="1.0" encoding="utf-8"?>
-<TextView xmlns:android="http://schemas.android.com/apk/res/android"
-    xmlns:tools="http://schemas.android.com/tools"
-    style="@style/TextAppearance.Vector.Body.Medium"
-    android:layout_width="match_parent"
-    android:layout_height="wrap_content"
-    android:background="@drawable/bg_space_item"
-    android:ellipsize="middle"
-    android:orientation="vertical"
-    android:padding="16dp"
-    android:singleLine="true"
-    android:text="@string/change_space"
-    android:textAllCaps="true"
-    android:textColor="?vctr_content_tertiary"
-    android:textSize="14sp"
-    tools:viewBindingIgnore="true" />

vector/src/main/res/values/strings.xml

@@ -139,7 +139,6 @@
     <string name="all_chats">All Chats</string>
     <string name="start_chat">Start Chat</string>
     <string name="create_room">Create Room</string>
-    <string name="change_space">Change Space</string>
     <string name="explore_rooms">Explore Rooms</string>
     <string name="a11y_expand_space_children">Expand space children</string>
     <string name="a11y_collapse_space_children">Collapse space children</string>

vector/src/test/java/im/vector/app/SpaceStateHandlerImplTest.kt

@@ -21,11 +21,13 @@ import im.vector.app.test.fakes.FakeActiveSessionHolder
 import im.vector.app.test.fakes.FakeAnalyticsTracker
 import im.vector.app.test.fakes.FakeSession
 import im.vector.app.test.fakes.FakeUiStateRepository
+import im.vector.app.test.fakes.FakeVectorPreferences
 import im.vector.app.test.fixtures.RoomSummaryFixture.aRoomSummary
 import kotlinx.coroutines.flow.first
 import kotlinx.coroutines.test.runTest
 import org.amshove.kluent.shouldBe
 import org.amshove.kluent.shouldBeEqualTo
+import org.junit.Before
 import org.junit.Test
 
 internal class SpaceStateHandlerImplTest {
@@ -38,14 +40,21 @@ internal class SpaceStateHandlerImplTest {
     private val uiStateRepository = FakeUiStateRepository()
     private val activeSessionHolder = FakeActiveSessionHolder(session)
     private val analyticsTracker = FakeAnalyticsTracker()
+    private val vectorPreferences = FakeVectorPreferences()
 
     private val spaceStateHandler = SpaceStateHandlerImpl(
             sessionDataSource.instance,
             uiStateRepository,
             activeSessionHolder.instance,
             analyticsTracker,
+            vectorPreferences.instance,
     )
 
+    @Before
+    fun setup() {
+        vectorPreferences.givenSpaceBackstack(emptyList())
+    }
+
     @Test
     fun `given selected space doesn't exist, when getCurrentSpace, then return null`() {
         val currentSpace = spaceStateHandler.getCurrentSpace()
@@ -77,33 +86,33 @@ internal class SpaceStateHandlerImplTest {
     }
 
     @Test
-    fun `given is forward navigation and no current space, when setCurrentSpace, then null added to backstack`() {
+    fun `given not in space and is forward navigation, when setCurrentSpace, then null added to backstack`() {
         spaceStateHandler.setCurrentSpace(spaceId, session, isForwardNavigation = true)
 
-        val backstack = spaceStateHandler.getSpaceBackstack()
+        vectorPreferences.verifySetSpaceBackstack(listOf(null))
-
-        backstack.size shouldBe 1
-        backstack.first() shouldBe null
     }
 
     @Test
-    fun `given is forward navigation and is in space, when setCurrentSpace, then previous space added to backstack`() {
+    fun `given in space and is forward navigation, when setCurrentSpace, then previous space added to backstack`() {
         spaceStateHandler.setCurrentSpace(spaceId, session, isForwardNavigation = true)
         spaceStateHandler.setCurrentSpace("secondSpaceId", session, isForwardNavigation = true)
 
-        val backstack = spaceStateHandler.getSpaceBackstack()
+        vectorPreferences.verifySetSpaceBackstack(listOf(spaceId))
-
-        backstack.size shouldBe 2
-        backstack shouldBeEqualTo listOf(null, spaceId)
     }
 
     @Test
     fun `given is not forward navigation, when setCurrentSpace, then previous space not added to backstack`() {
         spaceStateHandler.setCurrentSpace(spaceId, session, isForwardNavigation = false)
 
-        val backstack = spaceStateHandler.getSpaceBackstack()
+        vectorPreferences.verifySetSpaceBackstack(listOf(spaceId), inverse = true)
+    }
 
-        backstack.size shouldBe 0
+    @Test
+    fun `given navigating to all chats, when setCurrentSpace, then backstack cleared`() {
+        spaceStateHandler.setCurrentSpace(spaceId, session)
+        spaceStateHandler.setCurrentSpace(null, session)
+
+        vectorPreferences.verifySetSpaceBackstack(emptyList())
     }
 
     @Test

vector/src/test/java/im/vector/app/features/navigation/DefaultNavigatorTest.kt

@@ -0,0 +1,68 @@
+/*
+ * Copyright (c) 2022 New Vector Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package im.vector.app.features.navigation
+
+import im.vector.app.test.fakes.FakeActiveSessionHolder
+import im.vector.app.test.fakes.FakeAnalyticsTracker
+import im.vector.app.test.fakes.FakeContext
+import im.vector.app.test.fakes.FakeDebugNavigator
+import im.vector.app.test.fakes.FakeSpaceStateHandler
+import im.vector.app.test.fakes.FakeSupportedVerificationMethodsProvider
+import im.vector.app.test.fakes.FakeVectorFeatures
+import im.vector.app.test.fakes.FakeVectorPreferences
+import im.vector.app.test.fakes.FakeWidgetArgsBuilder
+import im.vector.app.test.fixtures.RoomSummaryFixture.aRoomSummary
+import org.junit.Test
+
+internal class DefaultNavigatorTest {
+
+    private val sessionHolder = FakeActiveSessionHolder()
+    private val vectorPreferences = FakeVectorPreferences()
+    private val widgetArgsBuilder = FakeWidgetArgsBuilder()
+    private val spaceStateHandler = FakeSpaceStateHandler()
+    private val supportedVerificationMethodsProvider = FakeSupportedVerificationMethodsProvider()
+    private val features = FakeVectorFeatures()
+    private val analyticsTracker = FakeAnalyticsTracker()
+    private val debugNavigator = FakeDebugNavigator()
+
+    private val navigator = DefaultNavigator(
+            sessionHolder.instance,
+            vectorPreferences.instance,
+            widgetArgsBuilder.instance,
+            spaceStateHandler,
+            supportedVerificationMethodsProvider.instance,
+            features,
+            analyticsTracker,
+            debugNavigator,
+    )
+
+    /**
+     * The below test is by no means all that we want to test in [DefaultNavigator].
+     * Please add relevant tests as you make changes to or related to other functions in the class.
+     */
+
+    @Test
+    fun `when switchToSpace, then current space set`() {
+        val spaceId = "space-id"
+        val spaceSummary = aRoomSummary(spaceId)
+        sessionHolder.fakeSession.fakeRoomService.getRoomSummaryReturns(spaceSummary)
+
+        navigator.switchToSpace(FakeContext().instance, spaceId, Navigator.PostSwitchSpaceAction.None)
+
+        spaceStateHandler.verifySetCurrentSpace(spaceId)
+    }
+}

vector/src/test/java/im/vector/app/test/fakes/FakeDebugNavigator.kt

@@ -0,0 +1,22 @@
+/*
+ * Copyright (c) 2022 New Vector Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package im.vector.app.test.fakes
+
+import im.vector.app.core.debug.DebugNavigator
+import io.mockk.mockk
+
+class FakeDebugNavigator : DebugNavigator by mockk()

vector/src/test/java/im/vector/app/test/fakes/FakeRoomService.kt

@@ -16,12 +16,18 @@
 
 package im.vector.app.test.fakes
 
+import io.mockk.every
 import io.mockk.mockk
 import org.matrix.android.sdk.api.session.room.RoomService
+import org.matrix.android.sdk.api.session.room.model.RoomSummary
 
 class FakeRoomService(
         private val fakeRoom: FakeRoom = FakeRoom()
 ) : RoomService by mockk() {
 
     override fun getRoom(roomId: String) = fakeRoom
+
+    fun getRoomSummaryReturns(roomSummary: RoomSummary?) {
+        every { getRoomSummary(any()) } returns roomSummary
+    }
 }

vector/src/test/java/im/vector/app/test/fakes/FakeSession.kt

@@ -37,7 +37,7 @@ class FakeSession(
         val fakeProfileService: FakeProfileService = FakeProfileService(),
         val fakeHomeServerCapabilitiesService: FakeHomeServerCapabilitiesService = FakeHomeServerCapabilitiesService(),
         val fakeSharedSecretStorageService: FakeSharedSecretStorageService = FakeSharedSecretStorageService(),
-        private val fakeRoomService: FakeRoomService = FakeRoomService(),
+        val fakeRoomService: FakeRoomService = FakeRoomService(),
         private val fakeEventService: FakeEventService = FakeEventService(),
 ) : Session by mockk(relaxed = true) {
 

vector/src/test/java/im/vector/app/test/fakes/FakeSpaceStateHandler.kt

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2021 New Vector Ltd
+ * Copyright (c) 2022 New Vector Ltd
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -14,14 +14,15 @@
  * limitations under the License.
  */
 
-package im.vector.app.features.spaces
+package im.vector.app.test.fakes
 
-import com.airbnb.epoxy.EpoxyModelClass
+import im.vector.app.SpaceStateHandler
-import im.vector.app.R
+import io.mockk.mockk
-import im.vector.app.core.epoxy.VectorEpoxyHolder
+import io.mockk.verify
-import im.vector.app.core.epoxy.VectorEpoxyModel
 
-@EpoxyModelClass
+class FakeSpaceStateHandler : SpaceStateHandler by mockk(relaxUnitFun = true) {
-abstract class NewSpaceListHeaderItem : VectorEpoxyModel<NewSpaceListHeaderItem.Holder>(R.layout.item_new_space_list_header) {
+
-    class Holder : VectorEpoxyHolder()
+    fun verifySetCurrentSpace(spaceId: String) {
+        verify { setCurrentSpace(spaceId) }
+    }
 }

vector/src/test/java/im/vector/app/test/fakes/FakeSupportedVerificationMethodsProvider.kt

@@ -0,0 +1,25 @@
+/*
+ * Copyright (c) 2022 New Vector Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package im.vector.app.test.fakes
+
+import im.vector.app.features.crypto.verification.SupportedVerificationMethodsProvider
+import io.mockk.mockk
+
+class FakeSupportedVerificationMethodsProvider {
+
+    val instance = mockk<SupportedVerificationMethodsProvider>()
+}

vector/src/test/java/im/vector/app/test/fakes/FakeVectorPreferences.kt

@@ -19,12 +19,21 @@ package im.vector.app.test.fakes
 import im.vector.app.features.settings.VectorPreferences
 import io.mockk.every
 import io.mockk.mockk
+import io.mockk.verify
 
 class FakeVectorPreferences {
 
-    val instance = mockk<VectorPreferences>()
+    val instance = mockk<VectorPreferences>(relaxUnitFun = true)
 
     fun givenUseCompleteNotificationFormat(value: Boolean) {
         every { instance.useCompleteNotificationFormat() } returns value
     }
+
+    fun givenSpaceBackstack(value: List<String?>) {
+        every { instance.getSpaceBackstack() } returns value
+    }
+
+    fun verifySetSpaceBackstack(value: List<String?>, inverse: Boolean = false) {
+        verify(inverse = inverse) { instance.setSpaceBackstack(value) }
+    }
 }

vector/src/test/java/im/vector/app/test/fakes/FakeWidgetArgsBuilder.kt

@@ -0,0 +1,25 @@
+/*
+ * Copyright (c) 2022 New Vector Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package im.vector.app.test.fakes
+
+import im.vector.app.features.widgets.WidgetArgsBuilder
+import io.mockk.mockk
+
+class FakeWidgetArgsBuilder {
+
+    val instance = mockk<WidgetArgsBuilder>()
+}