Wait until the sync has stopped before marking a background task as complete.

ElementX/Sources/Application/AppCoordinator.swift

@@ -882,12 +882,12 @@ class AppCoordinator: AppCoordinatorProtocol, AuthenticationFlowCoordinatorDeleg
 
     // MARK: - Application State
 
-    private func stopSync(isBackgroundTask: Bool) {
+    private func stopSync(isBackgroundTask: Bool, completion: (() -> Void)? = nil) {
         if isBackgroundTask, UIApplication.shared.applicationState == .active {
             // Attempt to stop the background task sync loop cleanly, only if the app not already running
             return
         }
-        userSession?.clientProxy.stopSync()
+        userSession?.clientProxy.stopSync(completion: completion)
         clientProxyObserver = nil
     }
 
@@ -968,9 +968,11 @@ class AppCoordinator: AppCoordinatorProtocol, AuthenticationFlowCoordinatorDeleg
         backgroundTask = appMediator.beginBackgroundTask { [weak self] in
             guard let self else { return }
 
-            stopSync(isBackgroundTask: true)
-
-            if let backgroundTask {
+            MXLog.info("Background task is about to expire.")
+            stopSync(isBackgroundTask: true) { [weak self] in
+                guard let self, let backgroundTask else { return }
+
+                MXLog.info("Ending background task.")
                 appMediator.endBackgroundTask(backgroundTask)
                 self.backgroundTask = nil
             }
@@ -1026,10 +1028,12 @@ class AppCoordinator: AppCoordinatorProtocol, AuthenticationFlowCoordinatorDeleg
         scheduleBackgroundAppRefresh()
 
         task.expirationHandler = { [weak self] in
-            self?.stopSync(isBackgroundTask: true)
+            MXLog.info("Background app refresh task is about to expire.")
 
-            MXLog.info("Background app refresh task expired")
-            task.setTaskCompleted(success: true)
+            self?.stopSync(isBackgroundTask: true) {
+                MXLog.info("Marking Background app refresh task as complete.")
+                task.setTaskCompleted(success: true)
+            }
         }
 
         guard let userSession else {
@@ -1047,13 +1051,14 @@ class AppCoordinator: AppCoordinatorProtocol, AuthenticationFlowCoordinatorDeleg
             .sink(receiveValue: { [weak self] _ in
                 guard let self else { return }
                 MXLog.info("Background app refresh finished")
+                backgroundRefreshSyncObserver?.cancel()
 
                 // Make sure we stop the sync loop, otherwise the ongoing request is immediately
                 // handled the next time the app refreshes, which can trigger timeout failures.
-                stopSync(isBackgroundTask: true)
-                backgroundRefreshSyncObserver?.cancel()
-
-                task.setTaskCompleted(success: true)
+                stopSync(isBackgroundTask: true) {
+                    MXLog.info("Marking Background app refresh task as complete.")
+                    task.setTaskCompleted(success: true)
+                }
             })
     }
 }

ElementX/Sources/Mocks/Generated/GeneratedMocks.swift

@@ -2346,6 +2346,41 @@ class ClientProxyMock: ClientProxyProtocol {
         stopSyncCallsCount += 1
         stopSyncClosure?()
     }
+    //MARK: - stopSync
+
+    var stopSyncCompletionUnderlyingCallsCount = 0
+    var stopSyncCompletionCallsCount: Int {
+        get {
+            if Thread.isMainThread {
+                return stopSyncCompletionUnderlyingCallsCount
+            } else {
+                var returnValue: Int? = nil
+                DispatchQueue.main.sync {
+                    returnValue = stopSyncCompletionUnderlyingCallsCount
+                }
+
+                return returnValue!
+            }
+        }
+        set {
+            if Thread.isMainThread {
+                stopSyncCompletionUnderlyingCallsCount = newValue
+            } else {
+                DispatchQueue.main.sync {
+                    stopSyncCompletionUnderlyingCallsCount = newValue
+                }
+            }
+        }
+    }
+    var stopSyncCompletionCalled: Bool {
+        return stopSyncCompletionCallsCount > 0
+    }
+    var stopSyncCompletionClosure: (((() -> Void)?) -> Void)?
+
+    func stopSync(completion: (() -> Void)?) {
+        stopSyncCompletionCallsCount += 1
+        stopSyncCompletionClosure?(completion)
+    }
     //MARK: - accountURL
 
     var accountURLActionUnderlyingCallsCount = 0

ElementX/Sources/Services/Client/ClientProxy.swift

@@ -305,7 +305,7 @@ class ClientProxy: ClientProxyProtocol {
         stopSync(completion: nil)
     }
 
-    private func stopSync(completion: (() -> Void)?) {
+    func stopSync(completion: (() -> Void)?) {
         MXLog.info("Stopping sync")
 
         if restartTask != nil {

ElementX/Sources/Services/Client/ClientProxyProtocol.swift

@@ -123,6 +123,7 @@ protocol ClientProxyProtocol: AnyObject, MediaLoaderProtocol {
     func startSync()
 
     func stopSync()
+    func stopSync(completion: (() -> Void)?) // Hopefully this will become async once we get SE-0371.
 
     func accountURL(action: AccountManagementAction) async -> URL?