Retrofit deferFulfillment onto snapshot tests. (#3641)

* Retrofit `deferFulfillment` onto snapshot tests.

* Convert a bunch of preview tests to the new fulfillment publisher

* Convert more tests

* Remove unneeded delays from the remaining tests

* Remove snapshotting delay option.

ElementX/Sources/Other/Extensions/Publisher.swift

@@ -36,3 +36,17 @@ extension Publisher where Output == String, Failure == Never {
         }
     }
 }
+
+extension Published.Publisher {
+    /// Returns the next output from the publisher skipping the current value stored into it (which is readable from the @Published property itself).
+    /// - Returns: the next output from the publisher
+    var nextValue: Output? {
+        get async {
+            var iterator = values.makeAsyncIterator()
+            
+            // skips the publisher's current value
+            _ = await iterator.next()
+            return await iterator.next()
+        }
+    }
+}

ElementX/Sources/Other/Extensions/Snapshotting.swift

@@ -14,33 +14,43 @@
 // limitations under the License.
 //
 
+import Combine
 import SwiftUI
 
-public struct SnapshotDelayPreferenceKey: PreferenceKey {
-    public static var defaultValue: TimeInterval = 0.0
+struct SnapshotPrecisionPreferenceKey: PreferenceKey {
+    static var defaultValue: Float = 1.0
 
-    public static func reduce(value: inout TimeInterval, nextValue: () -> TimeInterval) {
+    static func reduce(value: inout Float, nextValue: () -> Float) {
         value = nextValue()
     }
 }
 
-public struct SnapshotPrecisionPreferenceKey: PreferenceKey {
-    public static var defaultValue: Float = 1.0
+struct SnapshotPerceptualPrecisionPreferenceKey: PreferenceKey {
+    static var defaultValue: Float = 0.98
 
-    public static func reduce(value: inout Float, nextValue: () -> Float) {
+    static func reduce(value: inout Float, nextValue: () -> Float) {
         value = nextValue()
     }
 }
 
-public struct SnapshotPerceptualPrecisionPreferenceKey: PreferenceKey {
-    public static var defaultValue: Float = 0.98
+struct FulfillmentPublisherEquatableWrapper: Equatable {
+    let publisher: AnyPublisher<Bool, Never>?
+    
+    // Publisher equatability complicates things but, luckily, we're only interesting in them changing from nil
+    static func == (lhs: FulfillmentPublisherEquatableWrapper, rhs: FulfillmentPublisherEquatableWrapper) -> Bool {
+        lhs.publisher != nil && rhs.publisher != nil
+    }
+}
 
-    public static func reduce(value: inout Float, nextValue: () -> Float) {
+struct SnapshotFulfillmentPublisherPreferenceKey: PreferenceKey {
+    static var defaultValue: FulfillmentPublisherEquatableWrapper?
+
+    static func reduce(value: inout FulfillmentPublisherEquatableWrapper?, nextValue: () -> FulfillmentPublisherEquatableWrapper?) {
         value = nextValue()
     }
 }
 
-public extension SwiftUI.View {
+extension SwiftUI.View {
     /// Use this modifier when you want to apply snapshot-specific preferences,
     /// like delay and precision, to the view.
     /// These preferences can then be retrieved and used elsewhere in your view hierarchy.
@@ -49,10 +59,11 @@ public extension SwiftUI.View {
     ///   - delay: The delay time in seconds that you want to set as a preference to the View.
     ///   - precision: The percentage of pixels that must match.
     ///   - perceptualPrecision: The percentage a pixel must match the source pixel to be considered a match. 98-99% mimics the precision of the human eye.
-    @inlinable
-    func snapshotPreferences(delay: TimeInterval = .zero, precision: Float = 1.0, perceptualPrecision: Float = 0.98) -> some SwiftUI.View {
-        preference(key: SnapshotDelayPreferenceKey.self, value: delay)
-            .preference(key: SnapshotPrecisionPreferenceKey.self, value: precision)
+    func snapshotPreferences(expect fulfillmentPublisher: (any Publisher<Bool, Never>)? = nil,
+                             precision: Float = 1.0,
+                             perceptualPrecision: Float = 0.98) -> some SwiftUI.View {
+        preference(key: SnapshotPrecisionPreferenceKey.self, value: precision)
             .preference(key: SnapshotPerceptualPrecisionPreferenceKey.self, value: perceptualPrecision)
+            .preference(key: SnapshotFulfillmentPublisherPreferenceKey.self, value: FulfillmentPublisherEquatableWrapper(publisher: fulfillmentPublisher?.eraseToAnyPublisher()))
     }
 }

ElementX/Sources/Other/Extensions/XCTestCase.swift

@@ -0,0 +1,111 @@
+//
+// Copyright 2023, 2024 New Vector Ltd.
+//
+// SPDX-License-Identifier: AGPL-3.0-only
+// Please see LICENSE in the repository root for full details.
+//
+
+import Combine
+import XCTest
+
+extension XCTestCase {
+    /// XCTest utility that assists in subscribing to a publisher and deferring the fulfilment and results until some other actions have been performed.
+    /// - Parameters:
+    ///   - publisher: The publisher to wait on.
+    ///   - timeout: A timeout after which we give up.
+    ///   - message: An optional custom expectation message
+    ///   - until: callback that evaluates outputs until some condition is reached
+    /// - Returns: The deferred fulfilment to be executed after some actions and that returns the result of the publisher.
+    func deferFulfillment<P: Publisher>(_ publisher: P,
+                                        timeout: TimeInterval = 10,
+                                        message: String? = nil,
+                                        until condition: @escaping (P.Output) -> Bool) -> DeferredFulfillment<P.Output> {
+        var result: Result<P.Output, Error>?
+        let expectation = expectation(description: message ?? "Awaiting publisher")
+        var hasFullfilled = false
+        let cancellable = publisher
+            .sink { completion in
+                switch completion {
+                case .failure(let error):
+                    result = .failure(error)
+                    expectation.fulfill()
+                case .finished:
+                    break
+                }
+            } receiveValue: { value in
+                if condition(value), !hasFullfilled {
+                    result = .success(value)
+                    expectation.fulfill()
+                    hasFullfilled = true
+                }
+            }
+        
+        return DeferredFulfillment<P.Output> {
+            await self.fulfillment(of: [expectation], timeout: timeout)
+            cancellable.cancel()
+            let unwrappedResult = try XCTUnwrap(result, "Awaited publisher did not produce any output")
+            return try unwrappedResult.get()
+        }
+    }
+    
+    /// XCTest utility that assists in subscribing to a publisher and deferring the fulfilment and results until some other actions have been performed.
+    /// - Parameters:
+    ///   - publisher: The publisher to wait on.
+    ///   - keyPath: the key path for the expected values
+    ///   - transitionValues: the values through which the keypath needs to transition through
+    ///   - timeout: A timeout after which we give up.
+    ///   - message: An optional custom expectation message
+    /// - Returns: The deferred fulfilment to be executed after some actions and that returns the result of the publisher.
+    func deferFulfillment<P: Publisher, K: KeyPath<P.Output, V>, V: Equatable>(_ publisher: P,
+                                                                               keyPath: K,
+                                                                               transitionValues: [V],
+                                                                               timeout: TimeInterval = 10,
+                                                                               message: String? = nil) -> DeferredFulfillment<P.Output> {
+        var expectedOrder = transitionValues
+        let deferred = deferFulfillment<P>(publisher, timeout: timeout, message: message) { value in
+            let receivedValue = value[keyPath: keyPath]
+            if let index = expectedOrder.firstIndex(where: { $0 == receivedValue }), index == 0 {
+                expectedOrder.remove(at: index)
+            }
+            
+            return expectedOrder.isEmpty
+        }
+        
+        return deferred
+    }
+    
+    /// XCTest utility that assists in subscribing to a publisher and deferring the failure for a particular value until some other actions have been performed.
+    /// - Parameters:
+    ///   - publisher: The publisher to wait on.
+    ///   - timeout: A timeout after which we give up.
+    ///   - message: An optional custom expectation message
+    ///   - until: callback that evaluates outputs until some condition is reached
+    /// - Returns: The deferred fulfilment to be executed after some actions. The publisher's result is not returned from this fulfilment.
+    func deferFailure<P: Publisher>(_ publisher: P,
+                                    timeout: TimeInterval,
+                                    message: String? = nil,
+                                    until condition: @escaping (P.Output) -> Bool) -> DeferredFulfillment<Void> where P.Failure == Never {
+        let expectation = expectation(description: message ?? "Awaiting publisher")
+        expectation.isInverted = true
+        var hasFulfilled = false
+        let cancellable = publisher
+            .sink { value in
+                if condition(value), !hasFulfilled {
+                    expectation.fulfill()
+                    hasFulfilled = true
+                }
+            }
+        
+        return DeferredFulfillment<Void> {
+            await self.fulfillment(of: [expectation], timeout: timeout)
+            cancellable.cancel()
+        }
+    }
+    
+    struct DeferredFulfillment<T> {
+        let closure: () async throws -> T
+        @discardableResult func fulfill() async throws -> T {
+            try await closure()
+        }
+    }
+}

ElementX/Sources/Screens/Authentication/LoginScreen/View/LoginScreen.swift

@@ -136,20 +136,23 @@ struct LoginScreen_Previews: PreviewProvider, TestablePreview {
         NavigationStack {
             LoginScreen(context: viewModel.context)
         }
+        .snapshotPreferences(expect: viewModel.context.$viewState.map { state in
+            state.homeserver.loginMode == .password
+        })
         .previewDisplayName("matrix.org")
-        .snapshotPreferences(delay: 1)
         
         NavigationStack {
             LoginScreen(context: credentialsViewModel.context)
         }
+        .snapshotPreferences(expect: credentialsViewModel.context.$viewState.map { state in
+            state.homeserver.loginMode == .password
+        })
         .previewDisplayName("Credentials Entered")
-        .snapshotPreferences(delay: 1)
         
         NavigationStack {
             LoginScreen(context: unconfiguredViewModel.context)
         }
         .previewDisplayName("Unsupported")
-        .snapshotPreferences(delay: 1)
     }
     
     static func makeViewModel(homeserverAddress: String = "matrix.org", withCredentials: Bool = false) -> LoginScreenViewModel {

ElementX/Sources/Screens/Authentication/ServerSelectionScreen/View/ServerSelectionScreen.swift

@@ -107,7 +107,9 @@ struct ServerSelection_Previews: PreviewProvider, TestablePreview {
         NavigationStack {
             ServerSelectionScreen(context: invalidViewModel.context)
         }
-        .snapshotPreferences(delay: 1)
+        .snapshotPreferences(expect: invalidViewModel.context.$viewState.map { state in
+            state.hasValidationError == true
+        })
     }
     
     static func makeViewModel(for homeserverAddress: String) -> ServerSelectionScreenViewModel {

ElementX/Sources/Screens/CreateRoom/View/CreateRoomScreen.swift

@@ -332,12 +332,16 @@ struct CreateRoom_Previews: PreviewProvider, TestablePreview {
         NavigationStack {
             CreateRoomScreen(context: publicRoomInvalidAliasViewModel.context)
         }
-        .snapshotPreferences(delay: 1.5)
+        .snapshotPreferences(expect: publicRoomExistingAliasViewModel.context.$viewState.map { state in
+            !state.aliasErrors.isEmpty
+        })
         .previewDisplayName("Create Public Room, invalid alias")
         NavigationStack {
             CreateRoomScreen(context: publicRoomExistingAliasViewModel.context)
         }
-        .snapshotPreferences(delay: 1.5)
+        .snapshotPreferences(expect: publicRoomExistingAliasViewModel.context.$viewState.map { state in
+            !state.aliasErrors.isEmpty
+        })
         .previewDisplayName("Create Public Room, existing alias")
     }
 }

ElementX/Sources/Screens/EmojiPickerScreen/View/EmojiPickerScreen.swift

@@ -97,7 +97,9 @@ struct EmojiPickerScreen_Previews: PreviewProvider, TestablePreview {
     static var previews: some View {
         EmojiPickerScreen(context: viewModel.context, selectedEmojis: ["😀", "😄"])
             .previewDisplayName("Screen")
-            .snapshotPreferences(delay: 0.5)
+            .snapshotPreferences(expect: viewModel.context.$viewState.map { state in
+                !state.categories.isEmpty
+            })
     }
 }
 

ElementX/Sources/Screens/FilePreviewScreen/View/TimelineMediaPreviewDetailsView.swift

@@ -152,16 +152,17 @@ struct TimelineMediaPreviewDetailsView_Previews: PreviewProvider, TestablePrevie
         TimelineMediaPreviewDetailsView(item: viewModel.state.currentItem,
                                         context: viewModel.context)
             .previewDisplayName("Image")
-            .snapshotPreferences(delay: 0.1)
+            .snapshotPreferences(expect: viewModel.context.$viewState.map { state in
+                state.currentItemActions?.secondaryActions.contains(.redact) ?? false
+            })
+        
         TimelineMediaPreviewDetailsView(item: unknownTypeViewModel.state.currentItem,
                                         context: unknownTypeViewModel.context)
             .previewDisplayName("Unknown type")
-            .snapshotPreferences(delay: 0.1)
         
         TimelineMediaPreviewDetailsView(item: presentedOnRoomViewModel.state.currentItem,
                                         context: presentedOnRoomViewModel.context)
             .previewDisplayName("Incoming on Room")
-            .snapshotPreferences(delay: 0.1)
     }
     
     static func makeViewModel(contentType: UTType? = nil, isOutgoing: Bool = false, isPresentedOnRoomScreen: Bool = false) -> TimelineMediaPreviewViewModel {

ElementX/Sources/Screens/HomeScreen/View/HomeScreen.swift

@@ -196,19 +196,26 @@ struct HomeScreen_Previews: PreviewProvider, TestablePreview {
         NavigationStack {
             HomeScreen(context: loadingViewModel.context)
         }
+        .snapshotPreferences(expect: loadedViewModel.context.$viewState.map { state in
+            state.roomListMode == .skeletons
+        })
         .previewDisplayName("Loading")
         
         NavigationStack {
             HomeScreen(context: emptyViewModel.context)
         }
+        .snapshotPreferences(expect: emptyViewModel.context.$viewState.map { state in
+            state.roomListMode == .empty
+        })
         .previewDisplayName("Empty")
-        .snapshotPreferences(delay: 4.0)
         
         NavigationStack {
             HomeScreen(context: loadedViewModel.context)
         }
+        .snapshotPreferences(expect: loadedViewModel.context.$viewState.map { state in
+            state.roomListMode == .rooms
+        })
         .previewDisplayName("Loaded")
-        .snapshotPreferences(delay: 4.0)
     }
     
     static func viewModel(_ mode: HomeScreenRoomListMode) -> HomeScreenViewModel {

ElementX/Sources/Screens/JoinRoomScreen/View/JoinRoomScreen.swift

@@ -202,32 +202,42 @@ struct JoinRoomScreen_Previews: PreviewProvider, TestablePreview {
         NavigationStack {
             JoinRoomScreen(context: unknownViewModel.context)
         }
+        .snapshotPreferences(expect: unknownViewModel.context.$viewState.map { state in
+            state.roomDetails != nil
+        })
         .previewDisplayName("Unknown")
-        .snapshotPreferences(delay: 0.25)
         
         NavigationStack {
             JoinRoomScreen(context: knockViewModel.context)
         }
+        .snapshotPreferences(expect: knockViewModel.context.$viewState.map { state in
+            state.roomDetails != nil
+        })
         .previewDisplayName("Knock")
-        .snapshotPreferences(delay: 0.25)
         
         NavigationStack {
             JoinRoomScreen(context: joinViewModel.context)
         }
+        .snapshotPreferences(expect: joinViewModel.context.$viewState.map { state in
+            state.roomDetails != nil
+        })
         .previewDisplayName("Join")
-        .snapshotPreferences(delay: 0.25)
         
         NavigationStack {
             JoinRoomScreen(context: inviteViewModel.context)
         }
+        .snapshotPreferences(expect: inviteViewModel.context.$viewState.map { state in
+            state.roomDetails != nil
+        })
         .previewDisplayName("Invite")
-        .snapshotPreferences(delay: 0.25)
         
         NavigationStack {
             JoinRoomScreen(context: knockedViewModel.context)
         }
+        .snapshotPreferences(expect: knockedViewModel.context.$viewState.map { state in
+            state.roomDetails != nil
+        })
         .previewDisplayName("Knocked")
-        .snapshotPreferences(delay: 0.25)
     }
     
     static func makeViewModel(mode: JoinRoomScreenInteractionMode) -> JoinRoomScreenViewModel {

ElementX/Sources/Screens/KnockRequestsListScreen/View/KnockRequestsListScreen.swift

@@ -127,23 +127,32 @@ struct KnockRequestsListScreen_Previews: PreviewProvider, TestablePreview {
         NavigationStack {
             KnockRequestsListScreen(context: viewModel.context)
         }
-        .snapshotPreferences(delay: 0.2)
+        .snapshotPreferences(expect: viewModel.context.$viewState.map { state in
+            state.shouldDisplayRequests == true
+        })
         
         NavigationStack {
             KnockRequestsListScreen(context: singleRequestViewModel.context)
         }
+        .snapshotPreferences(expect: singleRequestViewModel.context.$viewState.map { state in
+            state.shouldDisplayRequests == true
+        })
         .previewDisplayName("Single Request")
-        .snapshotPreferences(delay: 0.2)
-
+        
         NavigationStack {
             KnockRequestsListScreen(context: emptyViewModel.context)
         }
+        .snapshotPreferences(expect: emptyViewModel.context.$viewState.map { state in
+            state.shouldDisplayEmptyView == true
+        })
         .previewDisplayName("Empty state")
-        .snapshotPreferences(delay: 0.2)
         
         NavigationStack {
             KnockRequestsListScreen(context: loadingViewModel.context)
         }
+        .snapshotPreferences(expect: loadingViewModel.context.$viewState.map { state in
+            state.isLoading == true
+        })
         .previewDisplayName("Loading state")
     }
 }

ElementX/Sources/Screens/Onboarding/IdentityConfirmationScreen/View/IdentityConfirmationScreen.swift

@@ -108,7 +108,9 @@ struct IdentityConfirmationScreen_Previews: PreviewProvider, TestablePreview {
         NavigationStack {
             IdentityConfirmationScreen(context: viewModel.context)
         }
-        .snapshotPreferences(delay: 1)
+        .snapshotPreferences(expect: viewModel.context.$viewState.map { state in
+            state.availableActions.contains([.interactiveVerification, .recovery])
+        })
     }
     
     private static var viewModel: IdentityConfirmationScreenViewModel {

ElementX/Sources/Screens/RoomDetailsEditScreen/View/RoomDetailsEditScreen.swift

@@ -174,12 +174,13 @@ struct RoomDetailsEditScreen_Previews: PreviewProvider, TestablePreview {
             RoomDetailsEditScreen(context: readOnlyViewModel.context)
         }
         .previewDisplayName("Read only")
-        .snapshotPreferences(delay: 0.25)
         
         NavigationStack {
             RoomDetailsEditScreen(context: editableViewModel.context)
         }
+        .snapshotPreferences(expect: editableViewModel.context.$viewState.map { state in
+            state.canEditTopic == true
+        })
         .previewDisplayName("Editable")
-        .snapshotPreferences(delay: 0.25)
     }
 }

ElementX/Sources/Screens/RoomDetailsScreen/View/RoomDetailsScreen.swift

@@ -419,13 +419,21 @@ struct RoomDetailsScreen_Previews: PreviewProvider, TestablePreview {
     
     static var previews: some View {
         RoomDetailsScreen(context: simpleRoomViewModel.context)
+            .snapshotPreferences(expect: simpleRoomViewModel.context.$viewState.map { state in
+                state.shortcuts.contains(.invite)
+            })
             .previewDisplayName("Simple Room")
-            .snapshotPreferences(delay: 2)
+        
         RoomDetailsScreen(context: dmRoomViewModel.context)
+            .snapshotPreferences(expect: dmRoomViewModel.context.$viewState.map { state in
+                state.accountOwner != nil
+            })
             .previewDisplayName("DM Room")
-            .snapshotPreferences(delay: 0.25)
+
         RoomDetailsScreen(context: genericRoomViewModel.context)
+            .snapshotPreferences(expect: genericRoomViewModel.context.$viewState.map { state in
+                state.shortcuts.contains(.invite)
+            })
             .previewDisplayName("Generic Room")
-            .snapshotPreferences(delay: 0.25)
     }
 }

ElementX/Sources/Screens/RoomDirectorySearchScreen/View/RoomDirectorySearchScreen.swift

@@ -98,6 +98,5 @@ struct RoomDirectorySearchScreen_Previews: PreviewProvider, TestablePreview {
     
     static var previews: some View {
         RoomDirectorySearchScreen(context: viewModel.context)
-            .snapshotPreferences(delay: 1.0)
     }
 }

ElementX/Sources/Screens/RoomMemberDetailsScreen/View/RoomMemberDetailsScreen.swift

@@ -139,17 +139,28 @@ struct RoomMemberDetailsScreen_Previews: PreviewProvider, TestablePreview {
     
     static var previews: some View {
         RoomMemberDetailsScreen(context: verifiedUserViewModel.context)
+            .snapshotPreferences(expect: verifiedUserViewModel.context.$viewState.map { state in
+                state.isVerified == true
+            })
             .previewDisplayName("Verified User")
-            .snapshotPreferences(delay: 0.25)
+            
         RoomMemberDetailsScreen(context: otherUserViewModel.context)
+            .snapshotPreferences(expect: otherUserViewModel.context.$viewState.map { state in
+                state.memberDetails?.role == .user
+            })
             .previewDisplayName("Other User")
-            .snapshotPreferences(delay: 0.25)
+            
         RoomMemberDetailsScreen(context: accountOwnerViewModel.context)
+            .snapshotPreferences(expect: accountOwnerViewModel.context.$viewState.map { state in
+                state.isOwnMemberDetails == true
+            })
             .previewDisplayName("Account Owner")
-            .snapshotPreferences(delay: 0.25)
+            
         RoomMemberDetailsScreen(context: ignoredUserViewModel.context)
+            .snapshotPreferences(expect: ignoredUserViewModel.context.$viewState.map { state in
+                state.memberDetails?.isIgnored ?? false
+            })
             .previewDisplayName("Ignored User")
-            .snapshotPreferences(delay: 0.25)
     }
     
     static func makeViewModel(member: RoomMemberProxyMock) -> RoomMemberDetailsScreenViewModel {

ElementX/Sources/Screens/RoomMemberListScreen/View/RoomMembersListManageMemberSheet.swift

@@ -72,13 +72,11 @@ struct RoomMembersListManageMemberSheet_Previews: PreviewProvider, TestablePrevi
                                          actions: [.kick, .ban],
                                          context: viewModel.context)
             .previewDisplayName("Joined")
-            .snapshotPreferences(delay: 0.2)
         
         RoomMembersListManageMemberSheet(member: .init(withProxy: RoomMemberProxyMock.mockBanned[3]),
                                          actions: [],
                                          context: viewModel.context)
             .previewDisplayName("Banned")
-            .snapshotPreferences(delay: 0.2)
     }
 }
 

ElementX/Sources/Screens/RoomMemberListScreen/View/RoomMembersListScreen.swift

@@ -117,31 +117,41 @@ struct RoomMembersListScreen_Previews: PreviewProvider, TestablePreview {
         NavigationStack {
             RoomMembersListScreen(context: viewModel.context)
         }
-        .snapshotPreferences(delay: 1.0)
+        .snapshotPreferences(expect: viewModel.context.$viewState.map { state in
+            !state.visibleJoinedMembers.isEmpty
+        })
         .previewDisplayName("Member")
         
         NavigationStack {
             RoomMembersListScreen(context: invitesViewModel.context)
         }
-        .snapshotPreferences(delay: 1.0)
+        .snapshotPreferences(expect: invitesViewModel.context.$viewState.map { state in
+            !state.visibleJoinedMembers.isEmpty
+        })
         .previewDisplayName("Invites")
         
         NavigationStack {
             RoomMembersListScreen(context: adminViewModel.context)
         }
-        .snapshotPreferences(delay: 1.0)
+        .snapshotPreferences(expect: adminViewModel.context.$viewState.map { state in
+            state.canBanUsers == true
+        })
         .previewDisplayName("Admin: Members")
         
         NavigationStack {
             RoomMembersListScreen(context: bannedViewModel.context)
         }
-        .snapshotPreferences(delay: 1.0)
+        .snapshotPreferences(expect: bannedViewModel.context.$viewState.map { state in
+            state.canBanUsers == true
+        })
         .previewDisplayName("Admin: Banned")
         
         NavigationStack {
             RoomMembersListScreen(context: emptyBannedViewModel.context)
         }
-        .snapshotPreferences(delay: 1.0)
+        .snapshotPreferences(expect: emptyBannedViewModel.context.$viewState.map { state in
+            state.canBanUsers == true
+        })
         .previewDisplayName("Admin: Empty Banned")
     }
     

ElementX/Sources/Screens/RoomPollsHistoryScreen/View/RoomPollsHistoryScreen.swift

@@ -151,12 +151,10 @@ struct RoomPollsHistoryScreen_Previews: PreviewProvider, TestablePreview {
             RoomPollsHistoryScreen(context: viewModelEmpty.context)
         }
         .previewDisplayName("No polls")
-        .snapshotPreferences(delay: 1.0)
 
         NavigationStack {
             RoomPollsHistoryScreen(context: viewModel.context)
         }
         .previewDisplayName("polls")
-        .snapshotPreferences(delay: 1.0)
     }
 }

ElementX/Sources/Screens/SecureBackup/SecureBackupRecoveryKeyScreen/View/SecureBackupRecoveryKeyScreen.swift

@@ -224,7 +224,7 @@ struct SecureBackupRecoveryKeyScreen: View {
 struct SecureBackupRecoveryKeyScreen_Previews: PreviewProvider, TestablePreview {
     static let key = "EsTM njec uHYA yHmh dQdW Nj4o bNRU 9jMN XGMc KUNM UFr5 R8GY"
     static let notSetUpViewModel = viewModel(recoveryState: .disabled)
-    static let generatingViewModel = viewModel(recoveryState: .disabled, generateKey: true)
+    static let generatingViewModel = viewModel(recoveryState: .disabled, generateKey: true, key: key)
     static let setupViewModel = viewModel(recoveryState: .enabled, generateKey: true, key: key)
     static let incompleteViewModel = viewModel(recoveryState: .incomplete)
     static let unknownViewModel = viewModel(recoveryState: .unknown)
@@ -239,14 +239,15 @@ struct SecureBackupRecoveryKeyScreen_Previews: PreviewProvider, TestablePreview
             SecureBackupRecoveryKeyScreen(context: generatingViewModel.context)
         }
         .previewDisplayName("Generating")
-        .snapshotPreferences(delay: 0.25)
         
         NavigationStack {
             SecureBackupRecoveryKeyScreen(context: setupViewModel.context)
         }
+        .snapshotPreferences(expect: setupViewModel.context.$viewState.map { state in
+            state.recoveryKey != nil
+        })
         .previewDisplayName("Set up")
-        .snapshotPreferences(delay: 0.25)
-
+        
         NavigationStack {
             SecureBackupRecoveryKeyScreen(context: incompleteViewModel.context)
         }

ElementX/Sources/Screens/SecureBackup/SecureBackupScreen/View/SecureBackupScreen.swift

@@ -125,28 +125,37 @@ struct SecureBackupScreen_Previews: PreviewProvider, TestablePreview {
     static let recoveryIncompleteViewModel = viewModel(keyBackupState: .enabled, recoveryState: .incomplete)
     
     static var previews: some View {
-        Group {
-            NavigationStack {
-                SecureBackupScreen(context: bothSetupViewModel.context)
-            }
-            .previewDisplayName("Both setup")
-            
-            NavigationStack {
-                SecureBackupScreen(context: onlyKeyBackupSetUpViewModel.context)
-            }
-            .previewDisplayName("Only key backup setup")
-            
-            NavigationStack {
-                SecureBackupScreen(context: keyBackupDisabledViewModel.context)
-            }
-            .previewDisplayName("Key backup disabled")
-            
-            NavigationStack {
-                SecureBackupScreen(context: recoveryIncompleteViewModel.context)
-            }
-            .previewDisplayName("Recovery incomplete")
+        NavigationStack {
+            SecureBackupScreen(context: bothSetupViewModel.context)
         }
-        .snapshotPreferences(delay: 1.0)
+        .snapshotPreferences(expect: bothSetupViewModel.context.$viewState.map { state in
+            state.keyBackupState == .enabled
+        })
+        .previewDisplayName("Both setup")
+        
+        NavigationStack {
+            SecureBackupScreen(context: onlyKeyBackupSetUpViewModel.context)
+        }
+        .snapshotPreferences(expect: onlyKeyBackupSetUpViewModel.context.$viewState.map { state in
+            state.keyBackupState == .enabled
+        })
+        .previewDisplayName("Only key backup setup")
+        
+        NavigationStack {
+            SecureBackupScreen(context: keyBackupDisabledViewModel.context)
+        }
+        .snapshotPreferences(expect: keyBackupDisabledViewModel.context.$viewState.map { state in
+            state.keyBackupState == .unknown
+        })
+        .previewDisplayName("Key backup disabled")
+        
+        NavigationStack {
+            SecureBackupScreen(context: recoveryIncompleteViewModel.context)
+        }
+        .snapshotPreferences(expect: recoveryIncompleteViewModel.context.$viewState.map { state in
+            state.recoveryState == .incomplete
+        })
+        .previewDisplayName("Recovery incomplete")
     }
     
     static func viewModel(keyBackupState: SecureBackupKeyBackupState,

ElementX/Sources/Screens/Settings/NotificationSettingsScreen/View/NotificationSettingsScreen.swift

@@ -253,9 +253,14 @@ struct NotificationSettingsScreen_Previews: PreviewProvider, TestablePreview {
 
     static var previews: some View {
         NotificationSettingsScreen(context: viewModel.context)
-            .snapshotPreferences(delay: 2.0)
+            .snapshotPreferences(expect: viewModel.context.$viewState.map { state in
+                state.settings != nil
+            })
+        
         NotificationSettingsScreen(context: viewModelConfigurationMismatch.context)
-            .snapshotPreferences(delay: 2.0)
+            .snapshotPreferences(expect: viewModelConfigurationMismatch.context.$viewState.map { state in
+                state.settings != nil
+            })
             .previewDisplayName("Configuration mismatch")
     }
 }

ElementX/Sources/Screens/Settings/SettingsScreen/View/SettingsScreen.swift

@@ -239,7 +239,9 @@ struct SettingsScreen_Previews: PreviewProvider, TestablePreview {
     static var previews: some View {
         NavigationStack {
             SettingsScreen(context: viewModel.context)
-                .snapshotPreferences(delay: 1.0)
+                .snapshotPreferences(expect: viewModel.context.$viewState.map { state in
+                    state.accountSessionsListURL != nil
+                })
         }
     }
 }

ElementX/Sources/Screens/Timeline/View/Replies/TimelineReplyView.swift

@@ -321,8 +321,6 @@ struct TimelineReplyView_Previews: PreviewProvider, TestablePreview {
         }
         .padding()
         .environmentObject(viewModel.context)
-        // Allow member names to load. Reduce precission as the `mockThumbnail` randomly renders slightly differently
-        .snapshotPreferences(delay: 0.2, precision: 0.98)
         .previewLayout(.sizeThatFits)
     }
 }

ElementX/Sources/Screens/Timeline/View/Style/TimelineItemBubbledStylerView.swift

@@ -355,14 +355,12 @@ struct TimelineItemBubbledStylerView_Previews: PreviewProvider, TestablePreview
             .previewDisplayName("Replies")
         threads
             .previewDisplayName("Thread decorator")
-            .snapshotPreferences(delay: 1)
             .previewLayout(.fixed(width: 390, height: 1700))
             .padding(.bottom, 20)
         encryptionAuthenticity
             .previewDisplayName("Encryption Indicators")
         pinned
             .previewDisplayName("Pinned messages")
-            .snapshotPreferences(delay: 1)
             .previewLayout(.fixed(width: 390, height: 1150))
             .padding(.bottom, 20)
     }

ElementX/Sources/Screens/Timeline/View/TimelineItemViews/FormattedBodyText.swift

@@ -205,6 +205,5 @@ struct FormattedBodyText_Previews: PreviewProvider, TestablePreview {
             .padding()
         }
         .previewLayout(.sizeThatFits)
-        .snapshotPreferences(delay: 0.25)
     }
 }

ElementX/Sources/Screens/UserProfileScreen/View/UserProfileScreen.swift

@@ -112,14 +112,22 @@ struct UserProfileScreen_Previews: PreviewProvider, TestablePreview {
     
     static var previews: some View {
         UserProfileScreen(context: verifiedUserViewModel.context)
+            .snapshotPreferences(expect: verifiedUserViewModel.context.$viewState.map { state in
+                state.isVerified != nil
+            })
             .previewDisplayName("Verified User")
-            .snapshotPreferences(delay: 0.25)
+        
         UserProfileScreen(context: otherUserViewModel.context)
+            .snapshotPreferences(expect: otherUserViewModel.context.$viewState.map { state in
+                state.isVerified != nil
+            })
             .previewDisplayName("Other User")
-            .snapshotPreferences(delay: 0.25)
+        
         UserProfileScreen(context: accountOwnerViewModel.context)
+            .snapshotPreferences(expect: accountOwnerViewModel.context.$viewState.map { state in
+                state.isVerified != nil
+            })
             .previewDisplayName("Account Owner")
-            .snapshotPreferences(delay: 0.25)
     }
     
     static func makeViewModel(userID: String) -> UserProfileScreenViewModel {