Xcode8 - failure during Swift migration process erroneously sets "hey I converted to Swift 3" state

Number:rdar://28265400 Date Originated:9/12/2016
Status:Open Resolved:
Product:Developer Tools Product Version:Version 8.0 (8A218a)
Classification:Serious Bug Reproducible:Always
I have a project (attached) that I tried to upgrade to Swift 3 from Swift 2.2

The migrator said "No changes necessary!", and marks the project as having been Swift 3 migrated

There's a build error due to no team being set in the "General Tab"

Fixed that, built - got a whole lot of errors.  It is swift 2.2 code after all and 

Did "convert to current swift syntax", and it said "this has already been updated to Swift 3.0" which is in fact, a lie.

Looks like the "hey, this has been updated to Swift 3" flag has been set before the update actually successfully runs. In this case, it fails, but the flag has already been set.  Now I have to curse at Xcode's lousy quality control (seems like this will be happening to just about _every_ Xcode 7 -> Swift 3 project, especially because the Swift migrator appears modally in the project before I can fix anything like fixing the team - which I hadn't had to do in any prior beta before GM) and re-run the migrator and tell it to go ahead and do the work it thought it did, but didn't.

Video attached showing the problem.

Steps to Reproduce:

Expected Results:

Actual Results:

Version 8.0 (8A218a)
10.11.6 (15G31)

It's really not that big a deal - just sigh at usual Xcode lossage and try the migration again, but when these kinds of things happen day-in, day-out, it's just another heavy-sigh death-of-a-thousand-cuts that makes using Xcode unpleasant


'CInterop.zip' and 'failed-migration.mp4' were successfully uploaded.


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