Add Xcode support policy

[mtrezza]

New Feature / Enhancement Checklist

• I am not disclosing a vulnerability.
• I am not just asking a question.
• I have searched through existing issues.

Current Limitation

This repo has no Xcode support policy, the CI currently runs a job for Xcode 14, which has been deprecated in Sept 2023. Maintaining the CI for older Xcode versions created additional efforts and its unclear how long we will and how long it makes sense to support older versions.

Feature / Enhancement Description

Policy context:

• Xcode major release every year in Sept.
• Every Xcode major release adds support for new Swift and iOS versions.
• Simulators for newest devices only available in new Xcode version

Historic Xcode release schedule:

• Xcode 14: Sept 2022
• Xcode 15: Sept 2023
• Xcode 16: Sept 2024

Historic iOS release schedule:

• iOS 16: Sept 2022
• iOS 17: Sept 2023
• iOS 18: Sept 2024

We can assume that developers adopt the newest Xcode version quickly after release, to test their app on newest device simulators and iOs versions.

I believe running the CI in the current and previous Xcode version is sufficient.

Tasks:

• Add support policy to README
• Remove job from unsupported Xcode versions from CI
  • feat: Remove support for Xcode 14 #1835

References:

• feat: Add PFObject.fromDictionary to create an object from dictionary #1834 (comment).

[parse-github-assistant]

Thanks for opening this issue!

• 🎉 We are excited about your ideas for improvement!

[mtrezza]

@dplewis What do you think?

[dplewis]

@mtrezza It's kinda hard to keep track because the github macos runners can update at anytime. Removing old Ruby versions, update default iOS SDK version, default Xcode version etc.

I believe we should support the latest version of the last Xcode version in our case 15.4 (default for macos-14-arm64 image).

For newer versions of Xcode is tricky because they would require you to download SDK that are missing which we couldn't do in the CI. This is the reason why I'm using 16.1 instead of 16.2 in #1835

Feel free to do a PR for Xcode support policy.

[mtrezza]

Good, the policy would only specify how long we support a Xcode major version, it wouldn't mandate which feature / patch version we use in the CI. I don't think it's important that we run on the latest Xcode feature or patch version, e.g. Xcode 16.1 vs. 16.2, we can choose whatever works. I'll ping you in the PR for review.

[mtrezza]

I've opened #1838 in an attempt to define a support policy for Xcode, iOS, macOS and watchOS. Apple doesn't have an official, published support schedule. I inferred the support dates from the Xcode support policy, assuming yearly releases.

The resulting table looks like this:

Xcode Version	iOS Version	macOS Version	macOS Version	Release Date	End-of-Support Date	Parse Apple SDK Support
Xcode 13	iOS 15	macOS 12	watchOS 8	September 2021	October 2022	>= 1.19.3 <2.7.2
Xcode 14	iOS 16	macOS 13	watchOS 9	September 2022	October 2023	>= 2.7.2
Xcode 15	iOS 17	macOS 14	watchOS 10	September 2023	October 2024	>= 3.0.0
Xcode 16	iOS 18	macOS 15	watchOS 11	September 2024	tbd	>= 4.2.0
Xcode 17	iOS 19	macOS 16	watchOS 12	tbd	tbd	tbd

Which means we would run a total of 6 CI jobs. For example as of today:

• Xcode 15:
  • iOS 17
  • macOS 14
  • watchOS 10
• Xcode 16:
  • iOS 18
  • macOS 15
  • watchOS 11

@dplewis Do you think it's easily possible to run these jobs? Or do you see any obstacles - it seems that PRs for CI jobs in this repo are often quite complex.

[parseplatformorg]

🎉 This change has been released in version 5.0.0