This post is from the WWDC26 SwiftUI Q&A.
I didn't hear any changes to testing in Swift Packages allowing UI tests. Maybe one day.
In the meantime what is your recommendation? I see, and have so far chosen to, add an 'example' project inside the package. This is a full fledged app that integrates the package.
My next issue is combining the xcresult file of the unit tests of the package, with the ui tests of the example app using the xcresulttool. I don't think it is meant to combine test results from different runs but I could be wrong. I got it working to combine results across different devices and languages of the same test plan but not different ones.