Custom attributes were not printed because they are marked
'UserInaccesible'.
* Make CustomAttr 'RejectByParser' instead of 'UserInaccessible'
* Remove special treatment for Result Builder attributes
* Load implicit modules in module/header interface gen requests
rdar://79927502
If a method has an `async` variant, the non-`async` variant will now mark its completion handler parameter `@Sendable`. This shouldn't be a breaking change in Swift 5 code since these declarations are automatically `@_predatesConcurrency`.
Also adds:
• Support for `@_nonSendable` on parameters, which can be used to override this implicit `@Sendable`
• Support for `@Sendable` on block typedefs; it's generally going to be a good idea to mark completion block typedefs `@Sendable`.
Fixes rdar://85569247.
Instead of a new attribute `@completionHandlerAsync`, allow the use of
the existing `renamed` parameter of `@available` to specify the
asynchronous alternative of a synchronous function.
No errors will be output from invalid names as `@completionHandlerAsync`
had, but if a function is correctly matched then it will be used to
output warnings when using the synchronous function in an asynchronous
context (as before).
Resolves rdar://80612731
Mark imported `@completionHandlerAsync` attrs as
implicit, which avoids printing them in generated
interfaces. And for the sake of completion,
serialize the implicit bit in case it's used
elsewhere in the future.
To make sure we continue to print
`@completionHandlerAsync` attributes explicitly
written by the user in Swift, add a SourceKit
interface test.
Resolves rdar://76685011
