If there is something wrong with the context, let's assign a default
KeyPath type to the key path literal to avoid propagating placeholder
into the key path inference.
For methods there are two possibilities - force unwrap and
conditional, that's why we need a disjunction with two choices.
This is not the case for key path root type it could only
be force unwrapped.
`tryMatchRootAndValueFromType` anchored both root and value match
constraints directly on the key path expression. That is incorrect
because we have special locators for that.
If key path literal is passed as an argument to a function/subscript
application its type cannot be resolved until the overload for the
call is selected, otherwise it could prevent a valid keypath-to-function
conversion in cases were argument ends up being a function type.
Instead of trying to get string representation of the type itself,
let's just get it based on the type name, which works well with the
list of types we have.
Resolves: rdar://113675093
I think from SIL's perspective, it should only worry about whether the
type is move-only. That includes MoveOnlyWrapped SILTypes and regular
types that cannot be copied.
Most of the code querying `SILType::isPureMoveOnly` is in SILGen, where
it's very likely that the original AST type is sitting around already.
In such cases, I think it's fine to ask the AST type if it is
noncopyable. The clarity of only asking the ASTType if it's noncopyable
is beneficial, I think.
`lookupConformance` request is not cached and constraint solver
performs a lot of them for the same type (i.e. during disjunction
solving), let's try to cache previously performed requests to
see whether additional memory use is worth the performance benefit.
getClosureActorIsolation.
This is preparation for changing AbstractClosureExpr to store
ActorIsolation instead of ClosureActorIsolation, and convert to
ClosureActorIsolation when needed to allow incrementally updating
callers. This change is NFC.
These allow multi-statement `if`/`switch` expression
branches that can produce a value at the end by
saying `then <expr>`. This is gated behind
`-enable-experimental-feature ThenStatements`
pending evolution discussion.
Checking type variables is no longer necessary because constraint
system now stores types of all closures it encountered, this makes
detection logic more reliable as well.
Resolves: rdar://112426330
The fix used incorrect locators for attempted argument conversions,
didn't check whether arguments are already re-ordered and allowed
fixes as visible side-effects from checking.
Resolves: rdar://114341979
A type variable that represents a key path literal cannot be bound
directly to `AnyKeyPath` or `PartialKeyPath`, such types could only
be used for conversions.
It used to be the task of the binding inference to infer `AnyKeyPath`
and `PartiaKeyPath` as a `KeyPath` using previously generated type
variables for a root and value associated with key path literal
(previously stored in the locator).
Recently we switched over to storing key path information in the
constraint system and introduced `resolveKeyPath` method to gain
more control over how key path type variable gets assigned.
Getting information from the constraint system creates a problem
for the inference because "undo" for some bindings would be run
after solver scope has been erased, so instead of modifying bindings
in `inferFromRelational`, let's do that in `resolveKeyPath` right
before the key path type variable gets bound which seems to be a
better place for that logic anyway.
Resolves: rdar://113760727
If type variable we are about to bind represents a pack
expansion type, allow the binding to happen regardless of
what the \c type is, because contextual type is just a hint
in this situation and type variable would be bound to its
opened type instead.
Resolves: rdar://112617922
If either source or destination type is a hole conversion should
just be ignored because there is no r-value or other mismatch that
could be diagnosed in this case.
Placeholder types just like type variables are set up to return
a conformance ref which, in this case, would mean that we'd produce
an invalid diagnostic.
Such tuples should be treated specially because once pack expansion
is sufficiently resolved they'd get exploded and the resulting type
is what member lookup should use as a base.
Resolves: rdar://110721928
`same-shape` mismatch detection logic shouldn't expect that types are
always packs because they could be either invalid (i.e. Void) or pack
archetypes too.
Resolves: rdar://112090069
by creating a BoundGenericType for the keypath expr
with the keypath base and replacing the value with
the value typeVar that will be resolved when the value
typeVar is directly bound.
