Record the initializer type as soon as we have a solution, before
it is applied, and get the type from the constriant system instead
of from the final type checked expression.
Note that the coerceToMaterializable() was unnecessary, since we
always coerce the value to an rvalue type with coerceToType().
Eventually coerceToMaterializable() should go away.
This is mostly NFC, except using the result of simplifyType() rather
than the type of the final expression changes some diagnostics where it
appears we were previously losing sugar.
Also this accidentally fixes a crasher. Unfortunately the underlying
issue is still there (applying a solution has bugs with opened
existentials "leaking" out) -- this merely masks the problem by
getting the initializer type directly from the constriant system.
And make an attempt to use the constraint system's contextualType to bind type information; this makes things better but doesn't seem to be a complete solution for contextually typing key paths.
It's particularly likely someone will try to type `\(foo)`, which looks like a string interpolation segment, outside of a string literal, so give that case a special diagnostic. Fixes rdar://problem/32315365.
It looks like the compiler is having troubles with the pattern when the
non-mutaing operator is defined on the protocol, and delegates to the
mutating version, that is provided by the concrete type. Adding similar
definitions of non-mutating operators to concrete types significantly
speeds up the typechecking of complex expressions, like the one in
the ByteSwap benchmark.
This is a bit more robust and user-friendly than hoping more brittle recovery in SILGen or IRGen for unsupported components kicks in. rdar://problem/32200714
```swift
func foo(f: Void) -> ()) {}
```
This compiler currently suggests we change this to:
```swift
func foo(f: (Void) -> ()) {}
```
That's `(()) -> ()`, almost certainly not what someone wants in Swift
4. We should suggest changing that to:
```swift
func foo(f: () -> ()) {}
```
Additionally,
```swift
func foo(f: (Void) -> ()) {}
```
Should trigger a warning that the `(Void)` input type is `(())`, and you
can't supply `()` to it in Swift 4, and suggest a fix-it change it to:
```swift
func foo(f: () -> ()) {}
```
rdar://problem/32143617
We had an inconsistency in the handling of ConstraintKind::Equal in that
we would take
$T1 Equal $T2
where $T2 was previously bound to a type, and bind the RValue type of
$T2's type to $T1. That does not allow for us to later attempt to bind
the LValue type of that type to $T1 (as might happen in simplifying an
OptionalObject constraint).
Instead, if $T1 can be bound to an LValue and $T2 is not an LValue,
we'll defer simplifying the Equal constraint until after $T1 is bound
through some other type variable binding or constraint simplification.
Fixes rdar://problem/31724272.
The delcared type was incorrect here as opposed to the type checker
incorrectly diagnosing a problem. Fix the test and add another test
without a subscript operation to ensure that it works.
We can't reliably decide in the parser if a type was forgotten or a
wrong type was meant to be a type (e.g. `let x: class MyClass`).
This patch applies a heuristic that the parameter was most likely
forgotten if the next character is a closing bracket or a semantic
separator.
This catches the most common cases of function parameters and variable
declarations that are immediately initialised.
This fixes SR-4785.
This introduces a few unfortunate things because the syntax is awkward.
In particular, the period and following token in \.[a], \.? and \.! are
token sequences that don't appear anywhere else in Swift, and so need
special handling. This is somewhat compounded by \foo.bar.baz possibly
being \(foo).bar.baz or \(foo.bar).baz (parens around the type), and,
furthermore, needing to distinguish \Foo?.bar from \Foo.?bar.
rdar://problem/31724243
(in Swift 4 mode)
There are a lot of other things that overload ranking does *not* take
into account, and I intend to file a more general bug about that, but
this should resolve some of the most egregious ambiguities with Swift
3's import rules (SE-0005, particularly "omit needless words" and
adding default arguments).
Finishes rdar://problem/25607552.
We would misreport a cast from G<T> to G<Int> or vice versa
as always failing, because we were checking for an exact
subtype relationship instead of archetype binding.
Fixes <https://bugs.swift.org/browse/SR-3609>.
If the -enable-experimental-subclass-existentials staging flag
is on, resolveType() now allows protocol compositions to contain
class types. It also diagnoses if a composition has more than one
superclass requirement.
Also, change diagnostics that talked about 'protocol composition'
to 'protocol-constrained type'.
Since such types can now contain a superclass constraint, it's not
correct to call them protocol composition.
"Protocol-constrained type" isn't quite accurate either because
'Any' has no protocols, and 'AnyObject' will have no protocols but
a general class constraint; but those are edge cases which won't
come up in these diagnostics.
TODO:
- Select the KeyPath subclass corresponding to the write capability of the key path components
- Figure out an issue with unresolved solutions being chosen with contextually-typed keypaths
- Diagnostic QoI
When in Swift 3 compatibility mode without
`-warn-swift3-objc-inference`, warn on the *uses* of declarations that
depend on the Objective-C runtime that became `@objc` due to the
deprecated inference rule. This far more directly captures important
uses of the deprecated Objective-C entrypoints. We diagnose:
* `#selector` expressions that refer to one of these `@objc` members
* `#keyPath` expressions that refer to one of these `@objc` members
* Dynamic lookup (i.e., member access via `AnyObject`) that refers to
one of these `@objc` members.
The "map into the right context" logic was only getting hit
if we didn't exit early to handle the lvalue case. Move it up
to the top of the function.
Fixes <https://bugs.swift.org/browse/SR-4369>.
rdar://problem/21193574 says that this warning dates back to when closure args before default args used to be considered as trailing closures. This is not the case anymore so Jordan suggested we remove the warning.
`1 { }` was parsed as a call expression with a trailing closure. This made the diagnostics for `var x = 1 { get { ... } }` extremely bad. Resolves SR-3671.