Code Completion not showing all possibilities

[Luceid71]

Swift version

6.23

Platform

Bazzite DX Linux

Editor

VSCode

Description

No response

Steps to Reproduce

Create a public interface A. create a fileprivate interface B that inherits A. Make an extension of B called C, giving it a public function. C's public function will not show up in autocomplete. I'm not sure if the functions on A and B were relevant or needed but that's how I had it set up.

Logging

sourcekit-lsp-23783.0.log
sourcekit-lsp-24850.0.log
sourcekit-lsp-26066.0.log
sourcekit-lsp-27899.0.log
sourcekit-lsp-35611.0.log

swift-versions.txt

[ahoppen]

Thanks for the bug report. I couldn’t see anything in your SourceKit-LSP logs that indicates a set-up error, so I suspect that the code completion machinery must be missing the member somewhere. I tried reproducing it using the following example but was unable to, both value and foo show up when completing in the following. Am I missing something in the set-up or are you trying to complete in a different location?

public protocol A {
    var value: Int { get }

    mutating func foo()
}

fileprivate protocol B: A {
    var value: Int { get set }

    mutating func foo()
}


extension B {
    mutating func foo() {
        self./*complete here*/
    }
}

[Luceid71]

Yes, I apologize for not being specific enough. It does appear that the autocomplete works just fine in the same file, but if you call it anywhere else, the autocomplete no longer works. However, if this were intended behavior, I should not be able to call the function at all in other locations, correct? So it still seems like a bug unless I am misunderstanding.

public protocol iStat
{
	var Value: Int {get}

	mutating func RecalculateValue()
}

fileprivate protocol iStatPrivate : iStat
{
	var Value: Int {get set}

	mutating func RecalculateValue()
}

extension iStatPrivate
{
	public mutating func RecalculateValue()
	{
		Value = 4
		GD.print("Test \(Value)")
	}
}

public class Stat : iStatPrivate
{
	fileprivate(set) public var Value: Int = 0

	init(){}
}

public class Testy
{
	var stat = Stat()
	
	public func Test()
	{
		// this autocomplete works just fine
		stat.RecalculateValue()
	}
}

// Some other file //

public class Testy2
{
	var stat = Stat()
	
	public func Test()
	{
		// Autocomplete cannot find this
		stat.RecalculateValue()
	}
}

[ahoppen]

Thanks for sharing the reproducer, @Luceid71. I was able to reduce it down a little further.

FileA.swift

public protocol BaseProto {
    func foo()
}

private protocol PrivateProto: BaseProto {
    func foo()
}

extension PrivateProto {
    func foo() {}
}

class MyStruct: PrivateProto {
    init() {}
}

FileB.swift

func test(myStruct: MyStruct) {
  myStruct.foo() // Complete `foo` here
}

I was honestly surprised that this compiles at all. I just checked this with recent Swift development snapshots and since swiftlang/swift#85846 this now produces a warning at the class definition saying: Method 'foo()' must be as accessible as its enclosing type because it matches a requirement in protocol 'BaseProto'.

The problem is that you are trying to satisfy a protocol requirement that requires internal access with a method that is only accessible at the (file)private access level, which isn’t supposed to be valid.

I’m going to close this issue since it’s not worth spending engineering time fixing this until this emits the warning I mentioned in released compiler and eventually becomes invalid with the StrictAccessControl upcoming language feature.