Add JSON stringifier for IAMs in unit tests

- Some unit tests were using an IAM's `jsonRepresentation` to use in server responses
- `jsonRepresentation` uses key of "messageId" so we need to replace that with "id" when working with the backend

- added `convertIAMtoJson` method that replaces "messageId" with "id"
- refactored code to use this method instead of `jsonRepresentation`

Author: nan-li

iOS_SDK/OneSignalSDK/UnitTests/InAppMessagingIntegrationTests.m

@@ -490,7 +490,8 @@ - (void)testIAMClickLaunchesAPIRequestMultipleTimes_Redisplay {
     let firstTrigger = [OSTrigger customTriggerWithProperty:@"prop1" withOperator:OSTriggerOperatorTypeExists withValue:nil];
 
     let message = [OSInAppMessageTestHelper testMessageWithTriggers:@[@[firstTrigger]] withRedisplayLimit:limit delay:@(delay)];
-    let registrationResponse = [OSInAppMessageTestHelper testRegistrationJsonWithMessages:@[message.jsonRepresentation]];
+    NSDictionary* json = [OSInAppMessageTestHelper convertIAMtoJson:message];
+    let registrationResponse = [OSInAppMessageTestHelper testRegistrationJsonWithMessages:@[json]];
 
     [OneSignalClientOverrider setMockResponseForRequest:NSStringFromClass([OSRequestRegisterUser class]) withResponse:registrationResponse];
 
@@ -1525,7 +1526,8 @@ - (void)testInAppMessageDisplayMultipleTimesSessionDurationTrigger {
     [OneSignal pauseInAppMessages:NO];
     let trigger = [OSTrigger dynamicTriggerWithKind:OS_DYNAMIC_TRIGGER_KIND_SESSION_TIME withOperator:OSTriggerOperatorTypeGreaterThanOrEqualTo withValue:@0];
     let message = [OSInAppMessageTestHelper testMessageWithTriggers:@[@[trigger]] withRedisplayLimit:5 delay:@30];
-    let registrationJson = [OSInAppMessageTestHelper testRegistrationJsonWithMessages:@[message.jsonRepresentation]];
+    NSDictionary* json = [OSInAppMessageTestHelper convertIAMtoJson:message];
+    let registrationJson = [OSInAppMessageTestHelper testRegistrationJsonWithMessages:@[json]];
 
     //Time interval mock
     NSDateComponents* comps = [[NSDateComponents alloc]init];
@@ -1642,7 +1644,8 @@ - (void)testIAMLifecyleEventsFired {
  Mock response JSON and initializes the OneSignal SDK
  */
 - (void)initOneSignalWithInAppMessage:(OSInAppMessageInternal *)message {
-    let registrationJson = [OSInAppMessageTestHelper testRegistrationJsonWithMessages:@[message.jsonRepresentation]];
+    NSDictionary* json = [OSInAppMessageTestHelper convertIAMtoJson:message];
+    let registrationJson = [OSInAppMessageTestHelper testRegistrationJsonWithMessages:@[json]];
     [self initOneSignalWithRegistrationJSON:registrationJson];
 }
 

iOS_SDK/OneSignalSDK/UnitTests/OSInAppMessagingHelpers.h

@@ -61,6 +61,7 @@ NS_ASSUME_NONNULL_BEGIN
 + (OSInAppMessageInternal *)testMessageWithTriggers:(NSArray <NSArray<OSTrigger *> *> *)triggers;
 + (OSInAppMessageInternal *)testMessageWithTriggers:(NSArray <NSArray<OSTrigger *> *> *)triggers withRedisplayLimit:(NSInteger)limit delay:(NSNumber *)delay;
 + (OSInAppMessageInternal *)testMessageWithPastEndTime:(BOOL)pastEndTime;
++ (NSDictionary *)convertIAMtoJson:(OSInAppMessageInternal *)message;
 + (NSDictionary *)testRegistrationJsonWithMessages:(NSArray<NSDictionary *> *)messages;
 + (NSDictionary *)testMessageJsonWithTriggerPropertyName:(NSString *)property withId:(NSString *)triggerId withOperator:(OSTriggerOperatorType)type withValue:(id)value;
 + (NSDictionary*)testInAppMessageGetContainsWithHTML:(NSString *)html;

iOS_SDK/OneSignalSDK/UnitTests/OSInAppMessagingHelpers.m

@@ -245,6 +245,14 @@ + (OSInAppMessageInternal *)testMessageWithTriggers:(NSArray <NSArray<OSTrigger
     return message;
 }
 
+// jsonRepresentation uses key of "messageId" but we need to use key of "id" for creating IAM, etc.
++ (NSDictionary *)convertIAMtoJson:(OSInAppMessageInternal *)message {
+    NSMutableDictionary *json = [message.jsonRepresentation mutableCopy];
+    json[@"id"] = message.messageId;
+    [json removeObjectForKey:@"messageId"];
+    return json;
+}
+
 + (NSDictionary *)testRegistrationJsonWithMessages:(NSArray<NSDictionary *> *)messages {
     return @{
         @"id" : @"1234",