[CodeCompletion] Do not offer completion Wrapped members for optional key path root type

[LucianoPAlmeida]

As described on the SR code completion is offering wrapped member for optional root key path type, which leads to invalid completions in some situations because using key path optional root to access wrapped members is invalid.

Resolves SR-13426.

[LucianoPAlmeida]

@swift-ci Please test

[LucianoPAlmeida]

cc @varungandhi-apple :)

[swift-ci]

Build failed
Swift Test OS X Platform
Git Sha - 919db68b36617ffffaad15fea3ecd042e69bd086

[LucianoPAlmeida]

@swift-ci Please test MacOS platform

[rintaro]

I think what we need to do is not removing . before ?.. The following example successfully compiles:

struct MyStruct {
  var value: Int { 1 }
}

func foo<T>(x: KeyPath<MyStruct?, T>) {}

let _ = foo(x: \.?.value)
let _ = foo(x: \MyStruct?.?.value)

[varungandhi-apple]

TIL \.?.value is legal syntax.

[theblixguy]

TIL as well. It looks like the grammar mentions it: https://docs.swift.org/swift-book/ReferenceManual/Expressions.html#grammar_key-path-components.

[LucianoPAlmeida]

TIL \.?.value is legal syntax.

I also didn't known this

Thanks @rintaro, I'll make the changes :)

[LucianoPAlmeida]

Changes applied to not erase the . for key path optional root type so completion will result in \.?.wrappedTypeMember
cc @rintaro

[rintaro]

@swift-ci Please smoke test

[rintaro]

Thank you!