@swift-ci create

Retracting my previous remarks as it does behave as intended and I misread the diagnostic text.

I will say that this sugar is terser but not necessarily clearer. The Swift Book, for example, does not mention that ? acts as sugar for .some. It's also gonna be hard to format the diagnostic text in general with and without sugar for nested cases.

I’ve decided to mark this as NTBF for the reasons above. The ?-style is a terser form of this, but given the choice between undocumented sugar and documented longer form, I’ll always take the latter. This also doesn’t have an impact on diagnostic quality.

You don't need the ? as of Swift 5.1, so I think this should suggest to add bar (and not bar? or .some(.bar) and none cases.

I take issue with that for the same reason. We should be spelling the long form since we don't want to have to look back at the way the subject was spelled (it can be an arbitrarily complex expression), and it's up to the user to apply whatever sugar they wish.