If we're using the macro-specific local discriminator, we need to
make sure we avoid mangling the regular local discriminator in
`appendDeclName`, since that could prematurely kick local discriminator
assignment before type-checking has finished.
rdar://143834482
For now the semantics provided by `@extensible` keyword on per-enum
basis. We might return this as an upcoming feature in the future with
a way to opt-out.
This attribute controls whether cross-module access to the declaration
needs `@unknown default:` because it's allowed to gain new cases even
if the module is non-resilient.
While here, fix some issues around implied isolated conformances (we
could get into an inconsistent state). Also provide an educational
note discussing isolated conformances and the kinds of errors one can
see when they are used from outside of their isolation domain.
The changes in https://github.com/swiftlang/swift/pull/80040 caused the
compiler to start diagnosing extensions containing only members that are
either `@_spi`, `@_alwaysEmitIntoClient`, or unavailable when the
`-require-explicit-availability` flag is passed. Extensions should not be
diagnosed when they only contain members that would not be diagnosed
themselves.
Resolves rdar://148275432.
When a generic function has potentially Escapable outputs, those outputs
declare lifetime dependencies, which have no effect when substitution
leads to those types becoming `Escapable` in a concrete context.
This means that type substitution should canonically eliminate lifetime
dependencies targeting Escapable parameters or returns, and that
type checking should allow a function value with potentially-Escapable
lifetime dependencies to bind to a function type without those dependencies
when the target of the dependencies is Escapable.
Fixes rdar://147533059.
Rather than fixing-up in the parser, adjust the ASTScope logic such
that a `try` element in a SequenceExpr is considered as covering all
elements to the right of it. Cases where this isn't true are invalid,
and will be diagnosed during sequence folding. e.g:
```
0 * try foo() + bar()
_ = try foo() ~~~ bar() // Assuming `~~~` has lower precedence than `=`
```
This ensures we correctly handle `try` in assignment sequences, and
allows ASTGen to get the behavior for free.
rdar://132872235
Suppose module 'Foo' exists in the search paths and specifies user module version '1.0'.
If the first encountered 'canImport' query is unversioned:
...
Followed by a versioned one:
...
The success of the first check will record an unversioned successful canImport, which will cause the second check to evaluate to 'true', which is incorrect.
This change causes even unversioned 'canImport' checks to track and record the discovered user module version.
