From 54ecb93f3c0e6f56a20d761a89b47422bf26819d Mon Sep 17 00:00:00 2001
From: evgeny <khokhlov.e.n@gmail.com>
Date: Mon, 9 Sep 2024 10:28:29 +0100
Subject: [PATCH 1/2] feat: use Cancellation object instead of unsubscribe
 methods

It's proven to be easier to manage to implement when subscription return object that you can use to unsubscribe
---
 .gitignore                                    |  1 +
 .../main/java/com/ably/chat/Cancellation.kt   | 12 ++++++++
 .../java/com/ably/chat/ConnectionStatus.kt    |  8 +----
 .../com/ably/chat/EmitsDiscontinuities.kt     |  8 +----
 .../src/main/java/com/ably/chat/Messages.kt   | 29 +++++--------------
 .../src/main/java/com/ably/chat/Occupancy.kt  | 21 ++------------
 .../src/main/java/com/ably/chat/Presence.kt   | 20 ++-----------
 .../main/java/com/ably/chat/RoomReactions.kt  | 19 ++----------
 .../src/main/java/com/ably/chat/RoomStatus.kt |  7 +----
 .../src/main/java/com/ably/chat/Typing.kt     | 19 ++----------
 10 files changed, 36 insertions(+), 108 deletions(-)
 create mode 100644 chat-android/src/main/java/com/ably/chat/Cancellation.kt

diff --git a/.gitignore b/.gitignore
index 4544f87..92c9f86 100644
--- a/.gitignore
+++ b/.gitignore
@@ -95,6 +95,7 @@ publish.properties
 /.idea/compiler.xml
 /.idea/jarRepositories.xml
 /.idea/misc.xml
+/.idea/shelf
 
 # general
 **/.DS_Store
diff --git a/chat-android/src/main/java/com/ably/chat/Cancellation.kt b/chat-android/src/main/java/com/ably/chat/Cancellation.kt
new file mode 100644
index 0000000..2357a1a
--- /dev/null
+++ b/chat-android/src/main/java/com/ably/chat/Cancellation.kt
@@ -0,0 +1,12 @@
+package com.ably.chat
+
+/**
+ * A cancellation handle, returned by various functions (mostly subscriptions)
+ * where cancellation is required.
+ */
+fun interface Cancellation {
+    /**
+     * Handle cancellation (unsubscribe listeners, clean up)
+     */
+    fun cancel()
+}
diff --git a/chat-android/src/main/java/com/ably/chat/ConnectionStatus.kt b/chat-android/src/main/java/com/ably/chat/ConnectionStatus.kt
index 6858f50..c9cc806 100644
--- a/chat-android/src/main/java/com/ably/chat/ConnectionStatus.kt
+++ b/chat-android/src/main/java/com/ably/chat/ConnectionStatus.kt
@@ -25,13 +25,7 @@ interface ConnectionStatus {
      * Registers a listener that will be called whenever the connection status changes.
      * @param listener The function to call when the status changes.
      */
-    fun on(listener: Listener)
-
-    /**
-     * Unregisters a listener
-     * @param listener The function to call when the status changes.
-     */
-    fun off(listener: Listener)
+    fun on(listener: Listener): Cancellation
 
     /**
      * An interface for listening to changes for the connection status
diff --git a/chat-android/src/main/java/com/ably/chat/EmitsDiscontinuities.kt b/chat-android/src/main/java/com/ably/chat/EmitsDiscontinuities.kt
index 10ffac6..6606bc2 100644
--- a/chat-android/src/main/java/com/ably/chat/EmitsDiscontinuities.kt
+++ b/chat-android/src/main/java/com/ably/chat/EmitsDiscontinuities.kt
@@ -10,13 +10,7 @@ interface EmitsDiscontinuities {
      * Register a listener to be called when a discontinuity is detected.
      * @param listener The listener to be called when a discontinuity is detected.
      */
-    fun onDiscontinuity(listener: Listener)
-
-    /**
-     * Unregister a listener to be called when a discontinuity is detected.
-     * @param listener The listener
-     */
-    fun offDiscontinuity(listener: Listener)
+    fun onDiscontinuity(listener: Listener): Cancellation
 
     /**
      * An interface for listening when discontinuity happens
diff --git a/chat-android/src/main/java/com/ably/chat/Messages.kt b/chat-android/src/main/java/com/ably/chat/Messages.kt
index 854b147..dc47679 100644
--- a/chat-android/src/main/java/com/ably/chat/Messages.kt
+++ b/chat-android/src/main/java/com/ably/chat/Messages.kt
@@ -3,7 +3,6 @@
 package com.ably.chat
 
 import io.ably.lib.realtime.Channel
-import io.ably.lib.types.PaginatedResult
 
 /**
  * This interface is used to interact with messages in a chat room: subscribing
@@ -24,13 +23,7 @@ interface Messages : EmitsDiscontinuities {
      * @param listener callback that will be called
      * @returns A response object that allows you to control the subscription.
      */
-    fun subscribe(listener: Listener)
-
-    /**
-     * Unsubscribe listener
-     * @param listener callback that will be unsubscribed
-     */
-    fun unsubscribe(listener: Listener)
+    fun subscribe(listener: Listener): MessagesSubscription
 
     /**
      * Get messages that have been previously sent to the chat room, based on the provided options.
@@ -176,6 +169,10 @@ data class SendMessageParams(
     val headers: MessageHeaders? = null,
 )
 
+interface MessagesSubscription : Cancellation {
+    suspend fun getPreviousMessages(queryOptions: QueryOptions): PaginatedResult<Message>
+}
+
 class DefaultMessages(
     private val roomId: String,
     private val realtimeClient: RealtimeClient,
@@ -190,25 +187,15 @@ class DefaultMessages(
     override val channel: Channel
         get() = realtimeClient.channels.get(messagesChannelName, ChatChannelOptions())
 
-    override fun subscribe(listener: Messages.Listener) {
+    override fun subscribe(listener: Messages.Listener): MessagesSubscription {
         TODO("Not yet implemented")
     }
 
-    override fun unsubscribe(listener: Messages.Listener) {
-        TODO("Not yet implemented")
-    }
-
-    override suspend fun get(options: QueryOptions): PaginatedResult<Message> {
-        TODO("Not yet implemented")
-    }
+    override suspend fun get(options: QueryOptions): PaginatedResult<Message> = chatApi.getMessages(roomId, options)
 
     override suspend fun send(params: SendMessageParams): Message = chatApi.sendMessage(roomId, params)
 
-    override fun onDiscontinuity(listener: EmitsDiscontinuities.Listener) {
-        TODO("Not yet implemented")
-    }
-
-    override fun offDiscontinuity(listener: EmitsDiscontinuities.Listener) {
+    override fun onDiscontinuity(listener: EmitsDiscontinuities.Listener): Cancellation {
         TODO("Not yet implemented")
     }
 }
diff --git a/chat-android/src/main/java/com/ably/chat/Occupancy.kt b/chat-android/src/main/java/com/ably/chat/Occupancy.kt
index 62a6bb0..95be9c4 100644
--- a/chat-android/src/main/java/com/ably/chat/Occupancy.kt
+++ b/chat-android/src/main/java/com/ably/chat/Occupancy.kt
@@ -23,14 +23,7 @@ interface Occupancy : EmitsDiscontinuities {
      *
      * @param listener A listener to be called when the occupancy of the room changes.
      */
-    fun subscribe(listener: Listener)
-
-    /**
-     * Unsubscribe a given listener to occupancy updates of the chat room.
-     *
-     * @param listener A listener to be unsubscribed.
-     */
-    fun unsubscribe(listener: Listener)
+    fun subscribe(listener: Listener): Cancellation
 
     /**
      * Get the current occupancy of the chat room.
@@ -72,11 +65,7 @@ internal class DefaultOccupancy(
     override val channel: Channel
         get() = messages.channel
 
-    override fun subscribe(listener: Occupancy.Listener) {
-        TODO("Not yet implemented")
-    }
-
-    override fun unsubscribe(listener: Occupancy.Listener) {
+    override fun subscribe(listener: Occupancy.Listener): Cancellation {
         TODO("Not yet implemented")
     }
 
@@ -84,11 +73,7 @@ internal class DefaultOccupancy(
         TODO("Not yet implemented")
     }
 
-    override fun onDiscontinuity(listener: EmitsDiscontinuities.Listener) {
-        TODO("Not yet implemented")
-    }
-
-    override fun offDiscontinuity(listener: EmitsDiscontinuities.Listener) {
+    override fun onDiscontinuity(listener: EmitsDiscontinuities.Listener): Cancellation {
         TODO("Not yet implemented")
     }
 }
diff --git a/chat-android/src/main/java/com/ably/chat/Presence.kt b/chat-android/src/main/java/com/ably/chat/Presence.kt
index ba49296..5987102 100644
--- a/chat-android/src/main/java/com/ably/chat/Presence.kt
+++ b/chat-android/src/main/java/com/ably/chat/Presence.kt
@@ -60,13 +60,7 @@ interface Presence : EmitsDiscontinuities {
      * Subscribe the given listener to all presence events.
      * @param listener listener to subscribe
      */
-    fun subscribe(listener: Listener)
-
-    /**
-     * Unsubscribe the given listener to all presence events.
-     * @param listener listener to unsubscribe
-     */
-    fun unsubscribe(listener: Listener)
+    fun subscribe(listener: Listener): Cancellation
 
     /**
      * An interface for listening to new presence event
@@ -162,19 +156,11 @@ internal class DefaultPresence(
         TODO("Not yet implemented")
     }
 
-    override fun subscribe(listener: Presence.Listener) {
-        TODO("Not yet implemented")
-    }
-
-    override fun unsubscribe(listener: Presence.Listener) {
-        TODO("Not yet implemented")
-    }
-
-    override fun onDiscontinuity(listener: EmitsDiscontinuities.Listener) {
+    override fun subscribe(listener: Presence.Listener): Cancellation {
         TODO("Not yet implemented")
     }
 
-    override fun offDiscontinuity(listener: EmitsDiscontinuities.Listener) {
+    override fun onDiscontinuity(listener: EmitsDiscontinuities.Listener): Cancellation {
         TODO("Not yet implemented")
     }
 }
diff --git a/chat-android/src/main/java/com/ably/chat/RoomReactions.kt b/chat-android/src/main/java/com/ably/chat/RoomReactions.kt
index f3a2d58..2c79339 100644
--- a/chat-android/src/main/java/com/ably/chat/RoomReactions.kt
+++ b/chat-android/src/main/java/com/ably/chat/RoomReactions.kt
@@ -38,12 +38,7 @@ interface RoomReactions : EmitsDiscontinuities {
      * @param listener The listener function to be called when a reaction is received.
      * @returns A response object that allows you to control the subscription.
      */
-    fun subscribe(listener: Listener)
-
-    /**
-     * Unsubscribe all listeners from receiving room-level reaction events.
-     */
-    fun unsubscribe(listener: Listener)
+    fun subscribe(listener: Listener): Cancellation
 
     /**
      * An interface for listening to new reaction events
@@ -116,19 +111,11 @@ internal class DefaultRoomReactions(
         TODO("Not yet implemented")
     }
 
-    override fun subscribe(listener: RoomReactions.Listener) {
-        TODO("Not yet implemented")
-    }
-
-    override fun unsubscribe(listener: RoomReactions.Listener) {
-        TODO("Not yet implemented")
-    }
-
-    override fun onDiscontinuity(listener: EmitsDiscontinuities.Listener) {
+    override fun subscribe(listener: RoomReactions.Listener): Cancellation {
         TODO("Not yet implemented")
     }
 
-    override fun offDiscontinuity(listener: EmitsDiscontinuities.Listener) {
+    override fun onDiscontinuity(listener: EmitsDiscontinuities.Listener): Cancellation {
         TODO("Not yet implemented")
     }
 }
diff --git a/chat-android/src/main/java/com/ably/chat/RoomStatus.kt b/chat-android/src/main/java/com/ably/chat/RoomStatus.kt
index 09f5b7a..82620b7 100644
--- a/chat-android/src/main/java/com/ably/chat/RoomStatus.kt
+++ b/chat-android/src/main/java/com/ably/chat/RoomStatus.kt
@@ -21,12 +21,7 @@ interface RoomStatus {
      * @param listener The function to call when the status changes.
      * @returns An object that can be used to unregister the listener.
      */
-    fun on(listener: Listener)
-
-    /**
-     * Removes all listeners that were added by the `onChange` method.
-     */
-    fun off(listener: Listener)
+    fun on(listener: Listener): Cancellation
 
     /**
      * An interface for listening to changes for the room status
diff --git a/chat-android/src/main/java/com/ably/chat/Typing.kt b/chat-android/src/main/java/com/ably/chat/Typing.kt
index fa75bc2..5de49f6 100644
--- a/chat-android/src/main/java/com/ably/chat/Typing.kt
+++ b/chat-android/src/main/java/com/ably/chat/Typing.kt
@@ -37,12 +37,7 @@ interface Typing : EmitsDiscontinuities {
      *
      * @param listener A listener to be called when the typing state of a user in the room changes.
      */
-    fun subscribe(listener: Listener)
-
-    /**
-     * Unsubscribe listeners from receiving typing events.
-     */
-    fun unsubscribe(listener: Listener)
+    fun subscribe(listener: Listener): Cancellation
 
     /**
      * Get the current typers, a set of clientIds.
@@ -89,11 +84,7 @@ internal class DefaultTyping(
     override val channel: Channel
         get() = realtimeClient.channels.get(typingIndicatorsChannelName, ChatChannelOptions())
 
-    override fun subscribe(listener: Typing.Listener) {
-        TODO("Not yet implemented")
-    }
-
-    override fun unsubscribe(listener: Typing.Listener) {
+    override fun subscribe(listener: Typing.Listener): Cancellation {
         TODO("Not yet implemented")
     }
 
@@ -109,11 +100,7 @@ internal class DefaultTyping(
         TODO("Not yet implemented")
     }
 
-    override fun onDiscontinuity(listener: EmitsDiscontinuities.Listener) {
-        TODO("Not yet implemented")
-    }
-
-    override fun offDiscontinuity(listener: EmitsDiscontinuities.Listener) {
+    override fun onDiscontinuity(listener: EmitsDiscontinuities.Listener): Cancellation {
         TODO("Not yet implemented")
     }
 }

From f5b2078981fc66e2ced91ac0e21f52dd10aed0c0 Mon Sep 17 00:00:00 2001
From: evgeny <khokhlov.e.n@gmail.com>
Date: Tue, 17 Sep 2024 12:45:15 +0100
Subject: [PATCH 2/2] chore: rename `Cancellation` to `Subscription` to avoid
 confusions with coroutine cancellation

---
 .../src/main/java/com/ably/chat/Cancellation.kt      | 12 ------------
 .../src/main/java/com/ably/chat/ConnectionStatus.kt  |  2 +-
 .../main/java/com/ably/chat/EmitsDiscontinuities.kt  |  2 +-
 chat-android/src/main/java/com/ably/chat/Messages.kt |  4 ++--
 .../src/main/java/com/ably/chat/Occupancy.kt         |  6 +++---
 chat-android/src/main/java/com/ably/chat/Presence.kt |  6 +++---
 .../src/main/java/com/ably/chat/RoomReactions.kt     |  6 +++---
 .../src/main/java/com/ably/chat/RoomStatus.kt        |  2 +-
 .../src/main/java/com/ably/chat/Subscription.kt      | 12 ++++++++++++
 chat-android/src/main/java/com/ably/chat/Typing.kt   |  6 +++---
 10 files changed, 29 insertions(+), 29 deletions(-)
 delete mode 100644 chat-android/src/main/java/com/ably/chat/Cancellation.kt
 create mode 100644 chat-android/src/main/java/com/ably/chat/Subscription.kt

diff --git a/chat-android/src/main/java/com/ably/chat/Cancellation.kt b/chat-android/src/main/java/com/ably/chat/Cancellation.kt
deleted file mode 100644
index 2357a1a..0000000
--- a/chat-android/src/main/java/com/ably/chat/Cancellation.kt
+++ /dev/null
@@ -1,12 +0,0 @@
-package com.ably.chat
-
-/**
- * A cancellation handle, returned by various functions (mostly subscriptions)
- * where cancellation is required.
- */
-fun interface Cancellation {
-    /**
-     * Handle cancellation (unsubscribe listeners, clean up)
-     */
-    fun cancel()
-}
diff --git a/chat-android/src/main/java/com/ably/chat/ConnectionStatus.kt b/chat-android/src/main/java/com/ably/chat/ConnectionStatus.kt
index c9cc806..2822f10 100644
--- a/chat-android/src/main/java/com/ably/chat/ConnectionStatus.kt
+++ b/chat-android/src/main/java/com/ably/chat/ConnectionStatus.kt
@@ -25,7 +25,7 @@ interface ConnectionStatus {
      * Registers a listener that will be called whenever the connection status changes.
      * @param listener The function to call when the status changes.
      */
-    fun on(listener: Listener): Cancellation
+    fun on(listener: Listener): Subscription
 
     /**
      * An interface for listening to changes for the connection status
diff --git a/chat-android/src/main/java/com/ably/chat/EmitsDiscontinuities.kt b/chat-android/src/main/java/com/ably/chat/EmitsDiscontinuities.kt
index 6606bc2..07412f4 100644
--- a/chat-android/src/main/java/com/ably/chat/EmitsDiscontinuities.kt
+++ b/chat-android/src/main/java/com/ably/chat/EmitsDiscontinuities.kt
@@ -10,7 +10,7 @@ interface EmitsDiscontinuities {
      * Register a listener to be called when a discontinuity is detected.
      * @param listener The listener to be called when a discontinuity is detected.
      */
-    fun onDiscontinuity(listener: Listener): Cancellation
+    fun onDiscontinuity(listener: Listener): Subscription
 
     /**
      * An interface for listening when discontinuity happens
diff --git a/chat-android/src/main/java/com/ably/chat/Messages.kt b/chat-android/src/main/java/com/ably/chat/Messages.kt
index dc47679..eb9600f 100644
--- a/chat-android/src/main/java/com/ably/chat/Messages.kt
+++ b/chat-android/src/main/java/com/ably/chat/Messages.kt
@@ -169,7 +169,7 @@ data class SendMessageParams(
     val headers: MessageHeaders? = null,
 )
 
-interface MessagesSubscription : Cancellation {
+interface MessagesSubscription : Subscription {
     suspend fun getPreviousMessages(queryOptions: QueryOptions): PaginatedResult<Message>
 }
 
@@ -195,7 +195,7 @@ class DefaultMessages(
 
     override suspend fun send(params: SendMessageParams): Message = chatApi.sendMessage(roomId, params)
 
-    override fun onDiscontinuity(listener: EmitsDiscontinuities.Listener): Cancellation {
+    override fun onDiscontinuity(listener: EmitsDiscontinuities.Listener): Subscription {
         TODO("Not yet implemented")
     }
 }
diff --git a/chat-android/src/main/java/com/ably/chat/Occupancy.kt b/chat-android/src/main/java/com/ably/chat/Occupancy.kt
index 95be9c4..a9e18ed 100644
--- a/chat-android/src/main/java/com/ably/chat/Occupancy.kt
+++ b/chat-android/src/main/java/com/ably/chat/Occupancy.kt
@@ -23,7 +23,7 @@ interface Occupancy : EmitsDiscontinuities {
      *
      * @param listener A listener to be called when the occupancy of the room changes.
      */
-    fun subscribe(listener: Listener): Cancellation
+    fun subscribe(listener: Listener): Subscription
 
     /**
      * Get the current occupancy of the chat room.
@@ -65,7 +65,7 @@ internal class DefaultOccupancy(
     override val channel: Channel
         get() = messages.channel
 
-    override fun subscribe(listener: Occupancy.Listener): Cancellation {
+    override fun subscribe(listener: Occupancy.Listener): Subscription {
         TODO("Not yet implemented")
     }
 
@@ -73,7 +73,7 @@ internal class DefaultOccupancy(
         TODO("Not yet implemented")
     }
 
-    override fun onDiscontinuity(listener: EmitsDiscontinuities.Listener): Cancellation {
+    override fun onDiscontinuity(listener: EmitsDiscontinuities.Listener): Subscription {
         TODO("Not yet implemented")
     }
 }
diff --git a/chat-android/src/main/java/com/ably/chat/Presence.kt b/chat-android/src/main/java/com/ably/chat/Presence.kt
index 5987102..2973e48 100644
--- a/chat-android/src/main/java/com/ably/chat/Presence.kt
+++ b/chat-android/src/main/java/com/ably/chat/Presence.kt
@@ -60,7 +60,7 @@ interface Presence : EmitsDiscontinuities {
      * Subscribe the given listener to all presence events.
      * @param listener listener to subscribe
      */
-    fun subscribe(listener: Listener): Cancellation
+    fun subscribe(listener: Listener): Subscription
 
     /**
      * An interface for listening to new presence event
@@ -156,11 +156,11 @@ internal class DefaultPresence(
         TODO("Not yet implemented")
     }
 
-    override fun subscribe(listener: Presence.Listener): Cancellation {
+    override fun subscribe(listener: Presence.Listener): Subscription {
         TODO("Not yet implemented")
     }
 
-    override fun onDiscontinuity(listener: EmitsDiscontinuities.Listener): Cancellation {
+    override fun onDiscontinuity(listener: EmitsDiscontinuities.Listener): Subscription {
         TODO("Not yet implemented")
     }
 }
diff --git a/chat-android/src/main/java/com/ably/chat/RoomReactions.kt b/chat-android/src/main/java/com/ably/chat/RoomReactions.kt
index 2c79339..06b214c 100644
--- a/chat-android/src/main/java/com/ably/chat/RoomReactions.kt
+++ b/chat-android/src/main/java/com/ably/chat/RoomReactions.kt
@@ -38,7 +38,7 @@ interface RoomReactions : EmitsDiscontinuities {
      * @param listener The listener function to be called when a reaction is received.
      * @returns A response object that allows you to control the subscription.
      */
-    fun subscribe(listener: Listener): Cancellation
+    fun subscribe(listener: Listener): Subscription
 
     /**
      * An interface for listening to new reaction events
@@ -111,11 +111,11 @@ internal class DefaultRoomReactions(
         TODO("Not yet implemented")
     }
 
-    override fun subscribe(listener: RoomReactions.Listener): Cancellation {
+    override fun subscribe(listener: RoomReactions.Listener): Subscription {
         TODO("Not yet implemented")
     }
 
-    override fun onDiscontinuity(listener: EmitsDiscontinuities.Listener): Cancellation {
+    override fun onDiscontinuity(listener: EmitsDiscontinuities.Listener): Subscription {
         TODO("Not yet implemented")
     }
 }
diff --git a/chat-android/src/main/java/com/ably/chat/RoomStatus.kt b/chat-android/src/main/java/com/ably/chat/RoomStatus.kt
index 82620b7..05e54e4 100644
--- a/chat-android/src/main/java/com/ably/chat/RoomStatus.kt
+++ b/chat-android/src/main/java/com/ably/chat/RoomStatus.kt
@@ -21,7 +21,7 @@ interface RoomStatus {
      * @param listener The function to call when the status changes.
      * @returns An object that can be used to unregister the listener.
      */
-    fun on(listener: Listener): Cancellation
+    fun on(listener: Listener): Subscription
 
     /**
      * An interface for listening to changes for the room status
diff --git a/chat-android/src/main/java/com/ably/chat/Subscription.kt b/chat-android/src/main/java/com/ably/chat/Subscription.kt
new file mode 100644
index 0000000..e2990a8
--- /dev/null
+++ b/chat-android/src/main/java/com/ably/chat/Subscription.kt
@@ -0,0 +1,12 @@
+package com.ably.chat
+
+/**
+ * An unsubscription handle, returned by various functions (mostly subscriptions)
+ * where unsubscription is required.
+ */
+fun interface Subscription {
+    /**
+     * Handle unsubscription (unsubscribe listeners, clean up)
+     */
+    fun unsubscribe()
+}
diff --git a/chat-android/src/main/java/com/ably/chat/Typing.kt b/chat-android/src/main/java/com/ably/chat/Typing.kt
index 5de49f6..6add59f 100644
--- a/chat-android/src/main/java/com/ably/chat/Typing.kt
+++ b/chat-android/src/main/java/com/ably/chat/Typing.kt
@@ -37,7 +37,7 @@ interface Typing : EmitsDiscontinuities {
      *
      * @param listener A listener to be called when the typing state of a user in the room changes.
      */
-    fun subscribe(listener: Listener): Cancellation
+    fun subscribe(listener: Listener): Subscription
 
     /**
      * Get the current typers, a set of clientIds.
@@ -84,7 +84,7 @@ internal class DefaultTyping(
     override val channel: Channel
         get() = realtimeClient.channels.get(typingIndicatorsChannelName, ChatChannelOptions())
 
-    override fun subscribe(listener: Typing.Listener): Cancellation {
+    override fun subscribe(listener: Typing.Listener): Subscription {
         TODO("Not yet implemented")
     }
 
@@ -100,7 +100,7 @@ internal class DefaultTyping(
         TODO("Not yet implemented")
     }
 
-    override fun onDiscontinuity(listener: EmitsDiscontinuities.Listener): Cancellation {
+    override fun onDiscontinuity(listener: EmitsDiscontinuities.Listener): Subscription {
         TODO("Not yet implemented")
     }
 }