Given something like `max(1, 2)` inside a type that conforms to Sequence, this
allows the compiler to consider Swift.max as well as the two methods with that
name on Sequence.
When the operand of a collection upcast is a dictionary literal,
upcast the elements of the collection instead. This avoids going
through the dynamic-casting machinery.
When we form a collection upcast of an array literal, upcast the
individual elements directly so we avoid a call through the
runtime. This both improves code generation and sidesteps a regression
involving the inability to dynamically cast function types.
Fixes SR-7362 / rdar://problem/39218656.
We just needed to select the final type based on which branch of the
disjunction successfully type-checked the expression.
Fixes [SR-7208](https://bugs.swift.org/browse/SR-7208)
and rdar://problem/37159360.
Instead of passing the base expression of a member access to `getAccessSemanticsFromContext`, we now just pass a bool flag for whether this is a member access on the implicit 'self' declaration.
Currently we always directly access a member when mutating it in its own didSet/willSet observer (in order to prevent infinite recursion). However we also do this even when accessing the same member on a *different* instance.
This commit changes the behaviour such that only member accesses on the implicit 'self' declaration are accessed directly within that member's own willSet/didSet.
Note that this change has the potential to cause recursion in cases where it didn't previously, for example this will now infinitely recurse:
struct S {
var i = 0 {
didSet {
var s = self
s.i = 5
}
}
}
var s = S()
s.i = 2
I don't know how serious this impact is though.
Resolves SR-419.
We need to ensure that the conformance is fully reified during type checking since we will use it during SILGen for the keypath. Speculative fix for SR-7207.
Allow certain bindings and conversions involving non-escaping
function types to succeed in "diagnostic" mode to gather fixes
and diagnose such problems better, expecially related to
conversions to 'Any' and generic parameters.
Resolves: rdar://problem/38648760
Some of the expressions call into `typeCheckExpressionShallow` while trying to
apply solutions, we need to respect the fact that sub-expressions might be
already properly type-checked while propagating l-value access kind.
Resolves: rdar://problem/38309176
When performing a binding/assignment to a weak or unowned variable/property from an initialiser call, emit a warning that the instance will be immediately deallocated.
We were inserting function conversion expressions that were then
turned into forces of values in cases where we merely referenced
functions, but did not actually call them.
Fixes rdar://problem/37241550.
We were not handling IUO results of @optional protocol methods
properly, sometimes forcing the @optional requirement rather than the
result of the call.
Fixes rdar://problem/37240984.
* Implement the recently accepted SE-0195 proposal, which introduces "Dynamic
Member Lookup" Types. This is a dusted off and updated version of PR13361,
which switches from DynamicMemberLookupProtocol to @dynamicMemberLookup as
was requested by the final review decision. This also rebases it,
updates it for other changes in the compiler, fixes a bunch of bugs, and adds support for keypaths.
Thank you to @rudx and @DougGregor in particular for the helpful review comments and test cases!
This is useful for explicit casts and type expressions, where
type loc and expression types might be different, and allows
constraint solver to avoid setting opened types to expressions
which resolves multiple crashes.
Allow functions with type `(()) -> T` to be passed in places where we
expect `() -> T`, but only for -swift-version 4 (for -swift-version 3
this already works due to other horrible things in CSSimplify.cpp).
We need to look at how we can help migrate these cases to
-swift-version 5, but in the meantime, but that is something we can
consider separately.
Generic parameters can become sources of metadata types and
conformances. To access them the layout needs to be available to IRGen.
rdar://37086144
SR-6879
This partially reverts commit 8685ee01a1.
The tests are still in place, but the code change is no longer necessary
now that IUOs are removed from the type system.
Fixes: rdar://problem/37013789
Stop creating ImplicitlyUnwrappedOptional<T> so that we can remove it
from the type system.
Enable the code that generates disjunctions for Optional<T> and
rewrites expressions based on the original declared type being 'T!'.
Most of the changes supporting this were previously merged to master,
but some things were difficult to merge to master without actually
removing IUOs from the type system:
- Dynamic member lookup and dynamic subscripting
- Changes to ensure the bridging peephole still works
Past commits have attempted to retain as much fidelity with how we
were printing things as possible. There are some cases where we still
are not printing things the same way:
- In diagnostics we will print '?' rather than '!'
- Some SourceKit and Code Completion output where we print a Type
rather than Decl.
Things like module printing via swift-ide-test attempt to print '!'
any place that we now have Optional types that were declared as IUOs.
There are some diagnostics regressions related to the fact that we can
no longer "look through" IUOs. For the same reason some output and
functionality changes in Code Completion. I have an idea of how we can
restore these, and have opened a bug to investigate doing so.
There are some small source compatibility breaks that result from
this change:
- Results of dynamic lookup that are themselves declared IUO can in
rare circumstances be inferred differently. This shows up in
test/ClangImporter/objc_parse.swift, where we have
var optStr = obj.nsstringProperty
Rather than inferring optStr to be 'String!?', we now infer this to
be 'String??', which is in line with the expectations of SE-0054.
The fact that we were only inferring the outermost IUO to be an
Optional in Swift 4 was a result of the incomplete implementation of
SE-0054 as opposed to a particular design. This should rarely cause
problems since in the common-case of actually using the property rather
than just assigning it to a value with inferred type, we will behave
the same way.
- Overloading functions with inout parameters strictly by a difference
in optionality (i.e. Optional<T> vs. ImplicitlyUnwrappedOptional<T>)
will result in an error rather than the diagnostic that was added
in Swift 4.1.
- Any place where '!' was being used where it wasn't supposed to be
allowed by SE-0054 will now treat the '!' as if it were '?'.
Swift 4.1 generates warnings for these saying that putting '!'
in that location is deprecated. These locations include for example
typealiases or any place where '!' is nested in another type like
`Int!?` or `[Int!]`.
This commit effectively means ImplicitlyUnwrappedOptional<T> is no
longer part of the type system, although I haven't actually removed
all of the code dealing with it yet.
ImplicitlyUnwrappedOptional<T> is is dead, long live implicitly
unwrapped Optional<T>!
Resolves rdar://problem/33272674.
