This change makes us treat it exactly as we do 'init'. We don't allow renaming the base name,
and don't fail if the basename doesn't match for calls.
Also:
- explicit init calls/references like `MyType.init(42)` are now reported with
'init' as a keywordBase range, rather than nothing.
- cursor info no longer reports rename as available on init/callAsFunction
calls without arguments, as there's nothing to rename in that case.
- Improved detection of when a referenced function is a call (rather than
reference) across syntactic rename, cursor-info, and indexing.
Resolves rdar://problem/60340429
Apply the same checks as ApplyExprs to
UnresolvedMemberExprs in getCalleeLocator to
resolve callees in cases where they're used with
`callAsFunction` in addition to a weird edge case
where we currently allow them with constructor
calls, e.g:
```
struct S {
static let s = S.self
}
let x: S = .s()
```
Arguably we should be representing ".member()"
expressions with an UnresolvedMemberExpr + CallExpr,
which would avoid the need to apply these special
cases, and reject the above syntax for not using
an explicit ".init". Doing so will likely require
a bit of hacking in CSGen though.
Resolves SR-11909.
We still want the constraint system to try looking up
a callAsFunction method even if it's inaccessible, as
we'll be able to record a fix and emit a suitable
diagnostic.
Rather than coercing the call arguments ourselves,
just build the finished member reference for the
callAsFunction method, and let finishApply do the
rest. This allows us to deal with transformations
such as IUO unwraps.
Resolves SR-11881.
Add a case to getCalleeLocator to return the
appropriate locator for a call to an implicit
callAsFunction member reference.
Resolves SR-11386 & SR-11778.
Introduce callables: values of types that declare `func callAsFunction`
methods can be called like functions. The call syntax is shorthand for
applying `func callAsFunction` methods.
```swift
struct Adder {
var base: Int
func callAsFunction(_ x: Int) -> Int {
return x + base
}
}
var adder = Adder(base: 3)
adder(10) // desugars to `adder.callAsFunction(10)`
```
`func callAsFunction` argument labels are required at call sites.
Multiple `func callAsFunction` methods on a single type are supported.
`mutating func callAsFunction` is supported.
SR-11378 tracks improving `callAsFunction` diagnostics.
