This hooks up call argument position completion to the typeCheckForCodeCompletion API to generate completions from all the solutions the constraint solver produces (even those requiring fixes), rather than relying on a single solution being applied to the AST (if any).
Co-authored-by: Nathan Hawes <nathan.john.hawes@gmail.com>
This ensures that opened archetypes always inherit any outer generic parameters from the context in which they reside. This matters because class bounds may bind generic parameters from these outer contexts, and without the outer context you can wind up with ill-formed generic environments like
<τ_0_0, where τ_0_0 : C<T>, τ_0_0 : P>
Where T is otherwise unbound because there is no entry for it among the generic parameters of the environment's associated generic signature.
Since `SolutionApplicationTarget` could represent whole statement
or pattern with multiple expressions, it makes sense to add a dedicated
method to pre-check everything together.
It's a convenient way to use existing logic for default argument inference
because suhc inference cannot open whole signature but only conformance
and layout constraints associated generic parameters used in a particular
parameter position.
When calling a generic function with an argument of existential type,
implicitly "open" the existential type into a concrete archetype, which
can then be bound to the generic type. This extends the implicit
opening that is performed when accessing a member of an existential
type from the "self" parameter to all parameters. For example:
func unsafeFirst<C: Collection>(_ c: C) -> C.Element { c.first! }
func g(c: any Collection) {
unsafeFirst(c) // currently an error
// with this change, succeeds and produces an 'Any'
}
This avoids many common sources of errors of the form
protocol 'P' as a type cannot conform to the protocol itself
which come from calling generic functions with an existential, and
allows another way "out" if one has an existention and needs to treat
it generically.
This feature is behind a frontend flag
`-enable-experimental-opened-existential-types`.
Instead of asking callers of `isExpired` to provide the threshold,
let's ask for that upfront. This change also allows us to check how
much time remains in the timer and build timers with different
thresholds without having to safe that information somewhere else.
Some implicit calls to `.callAsFunction` require that a new root
expression to be created for them in order to record argument list
and resolved overload choice.
Opaque opaque types and record them within the "opened types" of the
constraint system, then use that information to compute the set of
substitutions needed for the opaque type declaration using the normal
mechanism of the constraint solver. Record these substitutions within
the underlying-to-opaque conversion.
Use the recorded substitutions in the underlying-to-opaque conversion
to set the underlying substitutions for the opaque type declaration
itself, rather than reconstructing the substitutions in an ad hoc manner
that does not account for structural opaque result types.
When evaluating whether code is within a closure that uses concurrency
features, use the type of the closure as it's known during type checking,
so that contextual information (e.g., it's passed to a `@Sendable` or
`async` parameter of function type) can affect the result. This
corrects the definition for doing strict checking within a minimal
context for the end result of the type-check, rather than it's initial
state, catching more issues.
Fixes SR-15131 / rdar://problem/82535088.
Use this to enable better detection of async contexts when determining
whether to diagnose problems with concurrency.
Part of SR-15131 / rdar://problem/82535088.
We need to modify the pointer pointing to the cancellation flag when reusing an ASTContext for code completion. This is not possible by the previous design because `TypeCheckerOptions` was `const`. Moving the cancellation flag to `ASTContext` will also allow other stages of the compiler to honor a cancellation request.
Despite being otherwise disconnected from the
constraint system, it's possible for it to affect
how we type-check tuple matches in certain cases.
This is due to the fact that:
- It can have a lower type variable ID than an
opened generic parameter type, so becomes the
representative when merged with it. And because it
has a different locator, this can influence
binding prioritization.
- Tuple subtyping is broken, as it's currently a
*weaker* relationship than conversion.
Therefore, temporarily restore this bit of logic
for language versions < 6. If possible, we should
try and fix tuple subtying in Swift 6 mode to not
accept label mismatches, so that it's not more
permissive than tuple conversion.
rdar://85263844
If a type variable has a subtype binding which came from a conversion/subtype/equality
constraint to a struct or enum (expect to `AnyHashable`, `Unsafe{Mutable}RawPointer`),
attempt it early because that type is the only choice which is not going to fail such
constraint.
For example, in cases like `$T argument convertible to Int` type variable could
only be bound to `Int`, `Int!`, or `@lvalue Int` to satisfy that constraint, so
it would make sense to attempt to bind it to `Int` early if it doesn't represent
a result of a member lookup (that's how IUO and/or `@lvalue` could be inferred)`
and doesn't have any direct disjunction associated with it e.g. for coercion or
optional matching.
Caching the result here feels a little overkill as
it's only useful for one protocol, and the
`TypeChecker::getDefaultType` computation is
cached by the request evaluator.
For a non-public property where the type is defined by an assignment, like
`internal var internalAssigned = NewStruct()`, type-checking the type's
availability is done via checking the initializer expression.
In -check-api-availaiblity-only mode, pass down a flag to not check
availability in expressions for initializer expressions of such
non-public properties.
rdar://84389825
