[SR-7151] Generalize CaseIterable Synthesis for Availability

[CodaFi]

Previous ID	SR-7151
Radar	rdar://problem/43569215
Original Reporter	@CodaFi
Type	Improvement
Status	In Progress
Resolution

Additional Detail from JIRA

Votes	2
Component/s	Compiler
Labels	Improvement, StarterBug
Assignee	None
Priority	Medium

md5: 508eab090d1f0026b4428b290a2d40be

relates to:

• SR-9094 Unavailable enum case with synthesized raw value causes error

Issue Description:

As of this issue, the current implementation of SE-0194 does not synthesize a conformance if any cases contain an availability attribute. This restriction may be lifted at any time by an implementation that maintains the source-order invariant.

enum Rhapsody: CaseIterable {
  @available(*, unavailable)
  case inBlue 
  case hungarian, bohemian
  @available(*, deprecated)
  case onATheme
}
Rhapsody.allCases // [hungarian, bohemian, onATheme] 

[tkremenek]

@swift-ci create

[swift-ci]

Comment by Owen Voorhees (JIRA)

Tagging a bug I found while implementing this which will impact most use cases: SR-9094

[NKorotkov]

Any news on this issue? Swift 5.7, still a problem.