Add rtl6d1

Source/ARTProtocolMessage.m

@@ -6,6 +6,7 @@
 //  Copyright (c) 2014 Ably. All rights reserved.
 //
 
+#import "ARTDefault.h"
 #import "ARTProtocolMessage.h"
 #import "ARTProtocolMessage+Private.h"
 #import "ARTStatus.h"
@@ -85,6 +86,9 @@ - (BOOL)mergeFrom:(ARTProtocolMessage *)other {
      if (![other.channel isEqualToString:self.channel] || other.action != self.action) {
          return NO;
      }
+     if ([self mergeWouldExceedMaxSize:self.messages]) {
+         return NO;
+     }
 
      switch (self.action) {
          case ARTProtocolMessageMessage:
@@ -98,6 +102,24 @@ - (BOOL)mergeFrom:(ARTProtocolMessage *)other {
      }
 }
 
+- (BOOL)mergeWouldExceedMaxSize:(NSArray<ARTMessage*>*)messages {
+    NSInteger queuedMessagesSize = 0;
+    for (ARTMessage *message in self.messages) {
+        queuedMessagesSize += [message messageSize];
+    }
+    NSInteger messagesSize = 0;
+    for (ARTMessage *message in messages) {
+        messagesSize += [message messageSize];
+    }
+    NSInteger totalSize = queuedMessagesSize + messagesSize;
+    NSInteger maxSize = [ARTDefault maxMessageSize];
+    if (_connectionDetails.maxMessageSize) {
+        maxSize = _connectionDetails.maxMessageSize;
+    }
+    return totalSize > maxSize;
+}
+
+
 - (void)setConnectionSerial:(int64_t)connectionSerial {
     _connectionSerial =connectionSerial;
     _hasConnectionSerial = true;

Spec/RealtimeClientChannel.swift

@@ -2057,6 +2057,37 @@ class RealtimeClientChannel: QuickSpec {
                         }
                     }
                 }
+
+                // RTL6d1
+                it("The resulting ProtocolMessage must not exceed the maxMessageSize") {
+                    let options = AblyTests.commonAppSetup()
+                    options.autoConnect = false
+                    let client = AblyTests.newRealtime(options)
+                    defer { client.dispose(); client.close() }
+                    let channel = client.channels.get("test-maxMessageSize")
+                    // This amount of messages would be beyond maxMessageSize, if bundled together
+                    let messagesToBeSent = 1000
+
+                    // call publish before connecting, so messages are queued
+                    waitUntil(timeout: testTimeout*2) { done in
+                        let partialDone = AblyTests.splitDone(messagesToBeSent, done: done)
+                        for i in 1...messagesToBeSent {
+                            channel.publish("initial initial\(i)", data: "message message\(i)") { error in
+                                expect(error).to(beNil())
+                                partialDone()
+                            }
+                        }
+                        client.connect()
+                    }
+
+                    let transport = client.transport as! TestProxyTransport
+                    let protocolMessages = transport.protocolMessagesSent.filter{ $0.action == .message }
+                    // verify that messages are not bundled in a single protocol message
+                    expect(protocolMessages.count).to(beGreaterThan(1))
+                    // verify that all the messages have been sent
+                    let messagesSent = protocolMessages.compactMap{$0.messages?.count}.reduce(0, +)
+                    expect(messagesSent).to(equal(messagesToBeSent))
+                }
 
                 // RTL6e
                 context("Unidentified clients using Basic Auth") {