Rename OneSignalCore class to prevent conflict with the framework name

[nan-li]

Description

One Line Summary

Rename OneSignalCore class to prevent conflict with the framework name, which was causing Swift apps to have build errors.

Details

Motivation

After we released v5.1.1 with the new CD action and then v5.1.2 manually (thinking the error was due to the CD process), both releases caused Swift build errors in apps that looked like this.

I noticed only OneSignalFramework import was erroring. Using OneSignalUser or OneSignalCore directly was ok.

It is because of adding a class called OneSignalCore in the OneSignalCore framework in #1371. The Swift interface in OneSignalFramework had a conflict between the class name and framework name. No other modules have a Swift interface.

Renamed the class to OneSignalCoreImpl but considered other choices like "manager", "controller", etc.

Scope

Renaming internal class

Testing

Unit testing

None

Manual testing

• I tested this on my iphone 13 with ios 17.2
• I added the OneSignalXCFramework pod to a project using the local path to the iOS SDK and confirmed the error went away and the app built and ran successfully.
• I also confirmed I was using the correct version by testing a behavior change in Change OSPushSubscriptionState's "nil" json values to be "" #1373

Affected code checklist

• Notifications
  • Display
  • Open
  • Push Processing
  • Confirm Deliveries
• Outcomes
• Sessions
• In-App Messaging
• REST API requests
• Public API changes

Checklist

Overview

• I have filled out all REQUIRED sections above
• PR does one thing
• Any Public API changes are explained in the PR details and conform to existing APIs

Testing

• I have included test coverage for these changes, or explained why they are not needed
• All automated tests pass, or I explained why that is not possible
• I have personally tested this on my device, or explained why that is not possible

Final pass

• Code is as readable as possible.
• I have reviewed this PR myself, ensuring it meets each checklist item

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