Deprecating Old Xcode Patch Versions

A previously working Xcode build pipeline may start failing.

Our Xcode patch policy states that we retain the latest patch version of each Xcode major.minor version we support. Once a new patch version has been released, we will deprecate the previous patch version and redirect all requests to the new patch.

If your Fastlane configuration is relying on a hard-coded Xcode path, you may find that when a new patch version is realised that this will start to fail as the Xcode app path contains the version number of Xcode.

Example

You use the Xcode 12.1.0 image and specify /Applications/Xcode-12.1.app in one of your Fastlane actions.

We release Xcode 12.1.1 and redirect requests for 12.1.0 to this new image. Therefore the new Xcode app path is /Applications/Xcode-12.1.1.app and your job will fail on Path '/Applications/Xcode-12.1.app' doesn't exist

Best Practices for Avoiding Hard-coded Paths

In each image, we always symlink Xcode to a generic path. For example:

/Applications/Xcode-12.1.app -> /Applications/Xcode.app

The generic path remains consistent across all images, regardless of the Xcode version, and should be used for CircleCI jobs where possible.

We can also utilise a variable and CI environment test to avoid the use of a hard-coded path when running on CircleCI specifically. For example:

# fastlane/Fastfile

xcodePath = "/Applications/Xcode-12.1.app"

platform :iOS do
  before_all do
    setup_circle_ci
    if is_ci
      xcodePath = "/Applications/Xcode.app"
    end
  end
  ...
end

The above sets a variable, xcodePath, where we store the required path to Xcode. By using if is_ciwe can check whether the job is running on CircleCI and set the generic Xcode path if this is true. This allows you to continue using a hardcoded path when dealing with a local environment, if required, whilst using the generic symlinked path on CircleCI which helps prevent breaking changes between Xcode version changes.