IssueTracker

Versions

• AGP: 8.5.2 and 8.7.2 (possibly others)
• Kotlin: 2.0+

Description

We have encountered an issue when using R8 to minify & obfuscate published library artifact. When the library contains a Kotlin interface with a companion object which defines operator fun invoke() and the operator also has annotation @JvmName("someName") the invoke operator is removed (possibly inlined) from the artifact, but the signature is kept.

This issue is not apparent if the library module is directly used within the project in other module via the gradle dependency definition implementation(project(mylibrary)) and is present only if the published library artifact is used.

Sample:

Sample project: https://github.com/pavelreiter/r8-issue-interface-invoke

Example affected code:

package com.example.mylibrary

import androidx.annotation.Keep

@Keep
interface Configuration {
    val someString: String
    val someBool: Boolean

    @Keep
    companion object {
        @JvmName("getDefault")
        @JvmStatic
        @Keep
        operator fun invoke() : Configuration = object : Configuration {
            override val someString: String
                get() = "Configuration.getDefault()"
            override val someBool: Boolean
                get() = false
        }
    }
}

Example test

package com.example.mylibrary

import org.junit.Test

import org.junit.Assert.*

/**
 * Tests the invocation calls of [Configuration] and [Configuration2].
 */
class ExampleUnitTest {

    /**
     * This test fails because R8 removes the `operator fun invoke()` when using published artifact.
     */
    @Test
    fun configurationInvoke() {
        Configuration()
    }

    /**
     * The invoke call via JvmName functions as expected.
     */
    @Test
    fun configurationJavaProxy() {
        ConfigProxy.getDefault()
    }

    /**
     * The invoke call without JvmName annotation also works.
     */
    @Test
    fun configuration2WithoutJvmName() {
        Configuration2()
    }
}

The test configurationInvoke fails with java.lang.NoSuchMethodError: 'com.example.mylibrary.Configuration com.example.mylibrary.Configuration$Companion.invoke()'