[Index] Record the access level of declarations in the index

[ahoppen]

Depends on swiftlang/llvm-project#11716

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While updating the test cases, I noticed two slight oddities, for which I am happy with the current behavior, but I’m happy to be convinced by a different opinion.

• Function parameters are marked as fileprivate. I think we could make an argument that they should be marked as local instead of fileprivate even though they are indexed without index-locals enabled.
• Accessors such as willSet are marked as fileprivate. Since you can’t call them from anywhere else, I think this makes as much sense as anything. At least it matches the compiler’s effective access level.

rdar://163256878

[ahoppen]

swiftlang/llvm-project#11716

@swift-ci Please smoke test

[ahoppen]

swiftlang/llvm-project#11716

@swift-ci Please smoke test

[bnbarham]

• Function parameters are marked as fileprivate. I think we could make an argument that they should be marked as local instead of fileprivate even though they are indexed without index-locals enabled.
• Accessors such as willSet are marked as fileprivate. Since you can’t call them from anywhere else, I think this makes as much sense as anything. At least it matches the compiler’s effective access level.

My preference here would be to not include any access level for them.

Also CC @keith as IIRC you were thinking about adding access levels sometime in the past.

[bnbarham]

Access level was added to the index request (not the index itself) in #31942 and there was a long discussion there about whether it should be effective access or getFormalAccessScope, with the conclusion being getFormalAccessScope.

One notable case there was:

private enum E {
    case a, b, c
}
extension E {
    private func f() { print("Hello") }
}

Where apparently getEffectiveAccess gives fileprivate for f (which it isn't).

[ahoppen]

Great calls with the reference to the index request reporting access levels. I merged the two implementations, while at it also realized that we didn’t report the access level for macros in the old implementation.

One thing that crossed my mind while working on this: We only report access levels for definitions but both definitions and references are annotated as Local. Should we consider also only annotating declarations as Local?

[ahoppen]

swiftlang/llvm-project#11716

@swift-ci Please smoke test

[keith]

Thanks for the cc! I was definitely interested in this case, unfortunately because of the limited slack plan I can't scroll back to our discussion on my specific examples for why. But IIRC I wanted to use this for various lint rules about ACLs. I could see this helping with tools for automatically making imports private when possible, automatically downgrading ACLs, etc. So i'm very excited to see something like this land! cc @jpsim who might be interested as well