[ECO-5001] Some spec alignment

Example/AblyChatExample/Mocks/MockClients.swift

@@ -144,7 +144,7 @@ actor MockMessages: Messages {
         return message
     }
 
-    func subscribeToDiscontinuities() -> Subscription<ARTErrorInfo?> {
+    func subscribeToDiscontinuities() -> Subscription<DiscontinuityEvent> {
         fatalError("Not yet implemented")
     }
 }
@@ -195,7 +195,7 @@ actor MockRoomReactions: RoomReactions {
         .init(mockAsyncSequence: createSubscription())
     }
 
-    func subscribeToDiscontinuities() -> Subscription<ARTErrorInfo?> {
+    func subscribeToDiscontinuities() -> Subscription<DiscontinuityEvent> {
         fatalError("Not yet implemented")
     }
 }
@@ -244,7 +244,7 @@ actor MockTyping: Typing {
         }
     }
 
-    func subscribeToDiscontinuities() -> Subscription<ARTErrorInfo?> {
+    func subscribeToDiscontinuities() -> Subscription<DiscontinuityEvent> {
         fatalError("Not yet implemented")
     }
 }
@@ -348,7 +348,7 @@ actor MockPresence: Presence {
         .init(mockAsyncSequence: createSubscription())
     }
 
-    func subscribeToDiscontinuities() -> Subscription<ARTErrorInfo?> {
+    func subscribeToDiscontinuities() -> Subscription<DiscontinuityEvent> {
         fatalError("Not yet implemented")
     }
 }
@@ -383,7 +383,7 @@ actor MockOccupancy: Occupancy {
         OccupancyEvent(connections: 10, presenceMembers: 5)
     }
 
-    func subscribeToDiscontinuities() -> Subscription<ARTErrorInfo?> {
+    func subscribeToDiscontinuities() -> Subscription<DiscontinuityEvent> {
         fatalError("Not yet implemented")
     }
 }

Sources/AblyChat/DefaultMessages.swift

@@ -109,7 +109,7 @@ internal final class DefaultMessages: Messages, EmitsDiscontinuities {
     }
 
     // (CHA-M7) Users may subscribe to discontinuity events to know when there’s been a break in messages that they need to resolve. Their listener will be called when a discontinuity event is triggered from the room lifecycle.
-    internal func subscribeToDiscontinuities() async -> Subscription<ARTErrorInfo?> {
+    internal func subscribeToDiscontinuities() async -> Subscription<DiscontinuityEvent> {
         await featureChannel.subscribeToDiscontinuities()
     }
 

Sources/AblyChat/DefaultOccupancy.swift

@@ -50,7 +50,7 @@ internal final class DefaultOccupancy: Occupancy, EmitsDiscontinuities {
     }
 
     // (CHA-O5) Users may subscribe to discontinuity events to know when there’s been a break in occupancy. Their listener will be called when a discontinuity event is triggered from the room lifecycle. For occupancy, there shouldn’t need to be user action as most channels will send occupancy updates regularly as clients churn.
-    internal func subscribeToDiscontinuities() async -> Subscription<ARTErrorInfo?> {
+    internal func subscribeToDiscontinuities() async -> Subscription<DiscontinuityEvent> {
         await featureChannel.subscribeToDiscontinuities()
     }
 }

Sources/AblyChat/DefaultPresence.swift

@@ -194,7 +194,7 @@ internal final class DefaultPresence: Presence, EmitsDiscontinuities {
     }
 
     // (CHA-PR8) Users may subscribe to discontinuity events to know when there’s been a break in presence. Their listener will be called when a discontinuity event is triggered from the room lifecycle. For presence, there shouldn’t need to be user action as the underlying core SDK will heal the presence set.
-    internal func subscribeToDiscontinuities() async -> Subscription<ARTErrorInfo?> {
+    internal func subscribeToDiscontinuities() async -> Subscription<DiscontinuityEvent> {
         await featureChannel.subscribeToDiscontinuities()
     }
 

Sources/AblyChat/DefaultRoomLifecycleContributor.swift

@@ -3,7 +3,7 @@ import Ably
 internal actor DefaultRoomLifecycleContributor: RoomLifecycleContributor, EmitsDiscontinuities, CustomDebugStringConvertible {
     internal nonisolated let channel: DefaultRoomLifecycleContributorChannel
     internal nonisolated let feature: RoomFeature
-    private var discontinuitySubscriptions: [Subscription<ARTErrorInfo?>] = []
+    private var discontinuitySubscriptions: [Subscription<DiscontinuityEvent>] = []
 
     internal init(channel: DefaultRoomLifecycleContributorChannel, feature: RoomFeature) {
         self.channel = channel
@@ -12,14 +12,14 @@ internal actor DefaultRoomLifecycleContributor: RoomLifecycleContributor, EmitsD
 
     // MARK: - Discontinuities
 
-    internal func emitDiscontinuity(_ error: ARTErrorInfo?) {
+    internal func emitDiscontinuity(_ discontinuity: DiscontinuityEvent) {
         for subscription in discontinuitySubscriptions {
-            subscription.emit(error)
+            subscription.emit(discontinuity)
         }
     }
 
-    internal func subscribeToDiscontinuities() -> Subscription<ARTErrorInfo?> {
-        let subscription = Subscription<ARTErrorInfo?>(bufferingPolicy: .unbounded)
+    internal func subscribeToDiscontinuities() -> Subscription<DiscontinuityEvent> {
+        let subscription = Subscription<DiscontinuityEvent>(bufferingPolicy: .unbounded)
         // TODO: clean up old subscriptions (https://github.com/ably-labs/ably-chat-swift/issues/36)
         discontinuitySubscriptions.append(subscription)
         return subscription

Sources/AblyChat/DefaultRoomReactions.swift

@@ -80,7 +80,7 @@ internal final class DefaultRoomReactions: RoomReactions, EmitsDiscontinuities {
     }
 
     // (CHA-ER5) Users may subscribe to discontinuity events to know when there’s been a break in reactions that they need to resolve. Their listener will be called when a discontinuity event is triggered from the room lifecycle.
-    internal func subscribeToDiscontinuities() async -> Subscription<ARTErrorInfo?> {
+    internal func subscribeToDiscontinuities() async -> Subscription<DiscontinuityEvent> {
         await featureChannel.subscribeToDiscontinuities()
     }
 

Sources/AblyChat/DefaultTyping.swift

@@ -160,7 +160,7 @@ internal final class DefaultTyping: Typing {
     }
 
     // (CHA-T7) Users may subscribe to discontinuity events to know when there’s been a break in typing indicators. Their listener will be called when a discontinuity event is triggered from the room lifecycle. For typing, there shouldn’t need to be user action as the underlying core SDK will heal the presence set.
-    internal func subscribeToDiscontinuities() async -> Subscription<ARTErrorInfo?> {
+    internal func subscribeToDiscontinuities() async -> Subscription<DiscontinuityEvent> {
         await featureChannel.subscribeToDiscontinuities()
     }
 

Sources/AblyChat/EmitsDiscontinuities.swift

@@ -1,5 +1,14 @@
 import Ably
 
+public struct DiscontinuityEvent: Sendable, Equatable {
+    /// The error, if any, associated with this discontinuity.
+    public var error: ARTErrorInfo?
+
+    public init(error: ARTErrorInfo? = nil) {
+        self.error = error
+    }
+}
+
 public protocol EmitsDiscontinuities {
-    func subscribeToDiscontinuities() async -> Subscription<ARTErrorInfo?>
+    func subscribeToDiscontinuities() async -> Subscription<DiscontinuityEvent>
 }

Sources/AblyChat/Errors.swift

@@ -38,26 +38,25 @@ public enum ErrorCode: Int {
 
     /// The ``ARTErrorInfo.statusCode`` that should be returned for this error.
     internal var statusCode: Int {
-        // TODO: These are currently a guess, revisit once outstanding spec question re status codes is answered (https://github.com/ably/specification/pull/200#discussion_r1755222945), and also revisit in https://github.com/ably-labs/ably-chat-swift/issues/32
+        // These status codes are taken from the "Chat-specific Error Codes" section of the spec.
         switch self {
         case .nonspecific,
              .inconsistentRoomOptions,
-             .messagesDetachmentFailed,
-             .presenceDetachmentFailed,
-             .reactionsDetachmentFailed,
-             .occupancyDetachmentFailed,
-             .typingDetachmentFailed,
              .roomInFailedState,
              .roomIsReleasing,
              .roomIsReleased:
             400
         case
-            // TODO: These *AttachmentFailed ones are currently a best guess based on the limited status code information given in the spec at time of writing (i.e. CHA-RL1h4); it's not clear to me whether these error codes are always meant to have the same status code. Revisit once aforementioned spec question re status codes answered.
             .messagesAttachmentFailed,
             .presenceAttachmentFailed,
             .reactionsAttachmentFailed,
             .occupancyAttachmentFailed,
             .typingAttachmentFailed,
+            .messagesDetachmentFailed,
+            .presenceDetachmentFailed,
+            .reactionsDetachmentFailed,
+            .occupancyDetachmentFailed,
+            .typingDetachmentFailed,
             // CHA-RL9c
             .roomInInvalidState:
             500

Sources/AblyChat/RoomFeature.swift

@@ -58,7 +58,7 @@ internal struct DefaultFeatureChannel: FeatureChannel {
     internal var contributor: DefaultRoomLifecycleContributor
     internal var roomLifecycleManager: RoomLifecycleManager
 
-    internal func subscribeToDiscontinuities() async -> Subscription<ARTErrorInfo?> {
+    internal func subscribeToDiscontinuities() async -> Subscription<DiscontinuityEvent> {
         await contributor.subscribeToDiscontinuities()
     }