Fix autoclosure param interface type when it involves archetypes.
Had some repeated locals from moving this block of code around - cleaned up.
Alternate implementation where KeyPathExpr is essentially a literal type and can be either a KeyPath(R,V) or (R)->V.
Some unneccessary code now.
Implicit closure pieces need valid sourceLocs in case a coerce expr needs to refer to the beginning of the closure in `\.foo as (A) -> B`.
Removed explicit noescape from function type so `let a: (A) -> B = \.foo` is valid.
Remove optimization that optional path is always read-only KP type in CSGen, since it can also now be of function type.
Currently, because argument info has been collected based solely
on anchor, it would be possible to overwrite labels for expressions
like `foo[0](x)` since `ApplyExpr` uses its function expression as
a key for argument information cache, which leads to errors while
attempting optimizations based on that information.
Simplify the interface to gatherConstraints() by performing the
uniquing within the function itself and returning only the resulting
(uniqued) vector of constraints.
IDE functionality needs some internal type checking logics, e.g. checking
whether an extension is applicable to a concrete type. We used to directly
expose an header from sema called IDETypeChecking.h so that IDE functionalities
could invoke these APIs. The goal of the commit and following commits is to
expose evaluator requests instead of directly exposing function entry points from
sema so that we could later move IDETypeChecking.h to libIDE and implement these functions
by internally evaluating these requests.
```swift
protocol Proto {}
struct ConcreteProto {}
struct MyStruct<T> {}
extension MyStruct where T: Proto {
static var option: MyStruct<ConcreteProto> { get }
}
func foo<T: Proto>(arg: MyStruct<T>) {}
func test() {
foo(arg: .#^HERE^#)
}
```
In this case, the type of `MyStruct.option` is `MyStruct<ConcreteProto>`
whereas the context type is `MyStruct<T> where T: Proto`.
When checking the convertibility of them , we need to "open archetype types".
rdar://problem/24570603
rdar://problem/51723460
Don't filter out members if the base type has unresolved types.
Previously, initializers used to be hidden if the type has 'where'
requirements on the generic parameters.
This patch enables initializer completion for `SwiftUI.ForEach`.
rdar://problem/49480808
When multiple property wrapper attributes are provided on a declaration,
compose them outside-in to form a composite property wrapper type. For
example,
@A @B @C var foo = 17
will produce
var $foo = A(initialValue: B(initialValue: C(initialValue: 17)))
and foo's getter/setter will access "foo.value.value.value".
The implicit TypeExprs for function builders were getting inconsistently set
types, which would sometimes be the metatype and sometimes not be the
metatype, leading to a crash in the new test code.
Use the opened type from the callee declaration to open up references to
generic function builders that contain type parameters. This allows general
use of generic function builders.
Introduce an attribute @_disfavoredOverload that can be used to state
that a particular declaration should be avoided if there is a
successful type-check for a non-@_disfavoredOverload. It's a way to
nudge overload resolution away from particular solutions.
The initialization of an instance property that has an attached
property delegate involves the initial value written on the property
declaration, the implicit memberwise initializer, and the default
arguments to the implicit memberwise initializer. Implement SILGen
support for each of these cases.
There is a small semantic change to the creation of the implicit
memberwise initializer due to SE-0242 (default arguments for the
memberwise initializer). Specifically, the memberwise initializer will
use the original property type for the parameter to memberwise
initializer when either of the following is true:
- The corresponding property has an initial value specified with the
`=` syntax, e.g., `@Lazy var i = 17`, or
- The corresponding property has no initial value, but the property
delegate type has an `init(initialValue:)`.
The specific case that changed is when a property has an initial value
specified as a direct initialization of the delegate *and* the
property delegate type has an `init(initialValue:)`, e.g.,
```swift
struct X {
@Lazy(closure: { ... })
var i: Int
}
```
Previously, this would have synthesized an initializer:
```swift
init(i: Int = ???) { ... }
```
However, there is no way for the initialization specified within the
declaration of i to be expressed via the default argument. Now, it
synthesizes an initializer:
```swift
init(i: Lazy<Int> = Lazy(closure: { ... }))
```
A property with an attached delegate can be initialized in one of two ways:
* By directly specifying initialization arguments on the attribute,
e.g., "@SomeDelegate(x: 17, y: 42) var a".
* By initializing the original property itself, which goes through the
delegate type's init(initialValue:) initializer, e.g.,
"@Lazy var x = 17".
Implement support for both forms of initialization, including type
inference and checking for inconsistencies (e.g., if the annotation on
the property type doesn't match what the delegate type would
provide).
Previously, nearly all of the type vars for a key path component were dumped under the KeyPathExpr itself, whcih made them difficult to differentiate when debugging. Attach each one to “key path component #N -> function result” instead.
# Conflicts:
# lib/Sema/CSGen.cpp
We have a systemic class of issues where noescape types end up bound to
type variables in places that should not. The existing diagnostic for
this is ad-hoc and duplicated in several places but it doesn't actually
address the root cause of the problem.
For now, I've changed all call sites of createTypeVariable() to set the
new flag. I plan on removing enough occurrences of the flag to replicate
the old diagnostics. Then we can continue to refine this over time.
Type-check based diagnostics could introduce keypath dynamic member
expressions into AST, which have to be converted back to their
original member or subscript reference form before attempting
re-typecheck.
The use of the reference to a private implementation caused a silent
use-after-free which would normally not trigger a problem as the use was
pretty close by. The reference would copy the pointer and the
destructor for the implementation would free the backing memory. We
would then continue to use the free'd memory to query the information.
The Windows heap allocator kindly scribbles over the memory which caused
an invalid memory access, helping isolate the use-after-free.
Instead of building ArgumentShuffleExprs, lets just build a TupleExpr,
with explicit representation of collected varargs and default
arguments.
This isn't quite as elegant as it should be, because when re-typechecking,
SanitizeExpr needs to restore the 'old' parameter list by stripping out
the nodes inserted by type checking. However that hackery is all isolated
in one place and will go away soon.
Note that there's a minor change the generated SIL. Caller default
arguments (#file, #line, etc) are no longer delayed and are instead
evaluated in their usual argument position. I don't believe this actually
results in an observable change in behavior, but if it turns out to be
a problem, we can pretty easily change it back to the old behavior with a
bit of extra work.
VarargExpansionExpr shows up in call argument lists in synthesized
initializers and modify accessors when we need to forward arguments
to a call taking varargs.
Previously we would say that the type of VarargExpansionExpr is
$T when its subexpression type is [$T]. matchCallArguments() would
then 'collect' the single VarargExpansionExpr into a variadic
argument list with a single element, and build an ArgumentShuffleExpr
for the argument list.
In turn, SILGen would peephole vararg emission of a variadic
argument list with a single entry that happens to be a
VarargExpansionExpr, by returning the subexpression's value,
which happened to be an array of the right element type,
instead of building a new array containing the elements of the
variadic argument list.
This was all too complicated. Instead, let's say that the type of
a VarargExpansionExpr is [$T], except that when it appears in a
TupleExpr, the variadic bit of the corresponding element is set.
Then, matchCallArguments() needs to support a case where both
the parameter and argument list have a matching vararg element.
In this case, instead of collecting multiple arguments into a
single variadic argument list, we treat the variadic argument like
an ordinary parameter, bypassing construction of the
ArgumentShuffleExpr altogether.
Finally, SILGen now needs to be able to emit a VarargExpansionExpr
in ordinary rvalue position, since it now appears as a child of a
TupleExpr; it can do this by simply emitting the sub-expression
to produce an array value.
