private_to_this not considered in ABI analysis

[ZacSweers]

Plugin version
0.26.1

Gradle version
6.3

Android Gradle Plugin (AGP) version
Irrelevant

Describe the bug
Kotlin visibility has a notion of "private to this", which is present in metadata. I don't think this is currently accounted for.

To Reproduce
Steps to reproduce the behavior:

private class Foo

class Bar {
  private val foo = Foo()
}

Expected behavior
A clear and concise description of what you expected to happen.

Additional context
Add any other context about the problem here.

Example of reading the flag from metadata: https://github.com/square/kotlinpoet/blob/master/kotlinpoet-metadata/src/main/kotlin/com/squareup/kotlinpoet/metadata/Flags.kt#L46

[autonomousapps]

Are you sure? I just created a project with the only source file like this:

class Library {
    fun someLibraryMethod(): Boolean {
        val p = PrivateToThis()
        return true
    }
}

private class PrivateToThis

(most of this was auto-generated by gradle init)

I then ran ./gradlew abiAnalysisMain, which produced a file build/reports/dependency-analysis/main/abi-dump.txt, whose contents is

public final class abi/example/Library {
        public fun <init> ()V
        public final fun someLibraryMethod ()Z
}

(as expected)

The companion build/reports/dependency-analysis/main/abi.json file is empty.

nb, I'm not even allowed to compile something like this:

class Library {
    fun someLibraryMethod(): PrivateToThis {
        return PrivateToThis()
    }
}

private class PrivateToThis

[ZacSweers]

That case might not hit it exactly then. Maybe a private top level function?

[autonomousapps]

@ZacSweers are you seeing such PrivateToThis members showing up in an ABI report?

[ZacSweers]

Haven't seen any yet. Can close this out for now I think and just deal with it if it comes up