[Gradle] Check when Android library is published from kotlin managed

components.

This can lead into errors and mistakes. Android requires users to
explicitly configure publication on AGP side.
For example BuildTypeAttribute may leak into publication.

So in this diagnostic we will warn users that doing publications
incorrectly.

^KT-70380 Verification Pending

libraries/tools/kotlin-gradle-plugin-integration-tests/build.gradle.kts

@@ -94,6 +94,11 @@ dependencies {
     testCompileOnly(project(":kotlin-gradle-plugin-test-utils-embeddable"))
     testRuntimeOnly(project(":kotlin-gradle-plugin-test-utils-embeddable")) { isTransitive = false }
 
+    // AGP classes for buildScriptInjection's
+    testCompileOnly(libs.android.gradle.plugin.gradle.api) { isTransitive = false }
+    testCompileOnly(libs.android.gradle.plugin.gradle) { isTransitive = false }
+
+
     testImplementation(project(path = ":examples:annotation-processor-example"))
     testImplementation(kotlinStdlib("jdk8"))
     testImplementation(project(":kotlin-parcelize-compiler"))

libraries/tools/kotlin-gradle-plugin-integration-tests/src/test/kotlin/org/jetbrains/kotlin/gradle/android/KotlinAndroidMppIT.kt

@@ -5,6 +5,7 @@
 
 package org.jetbrains.kotlin.gradle.android
 
+import org.gradle.api.publish.maven.MavenPublication
 import org.gradle.testkit.runner.BuildResult
 import org.gradle.util.GradleVersion
 import org.jetbrains.kotlin.gradle.plugin.diagnostics.KotlinToolingDiagnostics
@@ -1068,4 +1069,38 @@ class KotlinAndroidMppIT : KGPBaseTest() {
             }
         }
     }
+
+    @DisplayName("KT-70380: KMM App failed to consume android binary lib when published incorrectly")
+    @GradleAndroidTest
+    @AndroidTestVersions(additionalVersions = [TestVersions.AGP.AGP_81])
+    @GradleTestVersions(additionalVersions = [TestVersions.Gradle.G_8_1, TestVersions.Gradle.G_8_2, TestVersions.Gradle.G_8_3])
+    fun kotlinAndroidHasBuildTypeAttribute(
+        gradleVersion: GradleVersion,
+        agpVersion: String,
+        jdkVersion: JdkVersions.ProvidedJdk,
+    ) {
+        kotlinAndroidLibraryProject(gradleVersion, agpVersion, jdkVersion).apply {
+            buildScriptInjection {
+                applyMavenPublishPlugin()
+                publishing.publications.create("default", MavenPublication::class.java) { publication ->
+                    publication.groupId = "com.example"
+                    publication.artifactId = "lib"
+                    publication.version = "1.0"
+
+                    project.afterEvaluate {
+                        publication.from(project.components.getByName("release"))
+                    }
+                }
+            }
+
+            build("publish") {
+                if (agpVersion == TestVersions.AGP.AGP_73) {
+                    // AGP 7.3 configures Publication automatically, so no diagnostic should be reported
+                    assertNoDiagnostic(KotlinToolingDiagnostics.AndroidPublicationNotConfigured)
+                } else {
+                    assertHasDiagnostic(KotlinToolingDiagnostics.AndroidPublicationNotConfigured)
+                }
+            }
+        }
+    }
 }

libraries/tools/kotlin-gradle-plugin-integration-tests/src/test/kotlin/org/jetbrains/kotlin/gradle/testbase/testGradleBuildInjection.kt

@@ -5,7 +5,11 @@
 
 package org.jetbrains.kotlin.gradle.testbase
 
+import com.android.build.api.dsl.LibraryExtension
 import org.gradle.api.Project
+import org.gradle.api.plugins.JavaPluginExtension
+import org.gradle.api.publish.PublishingExtension
+import org.jetbrains.kotlin.gradle.dsl.KotlinMultiplatformExtension
 import kotlin.io.path.appendText
 import kotlin.io.path.exists
 import kotlin.io.path.readText
@@ -76,7 +80,10 @@ annotation class BuildGradleKtsInjectionScope
 class GradleBuildScriptInjectionContext(
     val project: Project
 ) {
-    val kotlinMultiplatform get() = project.extensions.getByName("kotlin") as org.jetbrains.kotlin.gradle.dsl.KotlinMultiplatformExtension
+    val java get() = project.extensions.getByName("java") as JavaPluginExtension
+    val kotlinMultiplatform get() = project.extensions.getByName("kotlin") as KotlinMultiplatformExtension
+    val androidLibrary get() = project.extensions.getByName("android") as LibraryExtension
+    val publishing get() = project.extensions.getByName("publishing") as PublishingExtension
     val dependencies get() = project.dependencies
 }
 

libraries/tools/kotlin-gradle-plugin-integration-tests/src/test/kotlin/org/jetbrains/kotlin/gradle/testbase/testProjectsBuildScriptInjectionDsl.kt

@@ -0,0 +1,50 @@
+/*
+ * Copyright 2010-2024 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
+ */
+
+package org.jetbrains.kotlin.gradle.testbase
+
+import org.gradle.api.publish.PublishingExtension
+import org.gradle.jvm.toolchain.JavaLanguageVersion
+import org.gradle.util.GradleVersion
+
+fun KGPBaseTest.kotlinAndroidLibraryProject(
+    gradleVersion: GradleVersion,
+    agpVersion: String,
+    jdkVersion: JdkVersions.ProvidedJdk,
+): TestProject {
+    return project(
+        "base-kotlin-android-library",
+        gradleVersion,
+        buildOptions = defaultBuildOptions.copy(androidVersion = agpVersion),
+        buildJdk = jdkVersion.location,
+    ) {
+        buildScriptInjection { applyDefaultAndroidLibraryConfiguration() }
+    }
+}
+
+fun GradleBuildScriptInjectionContext.applyMavenPublishPlugin(): PublishingExtension {
+    project.plugins.apply("maven-publish")
+    publishing.repositories.apply {
+        maven { maven ->
+            maven.setUrl(project.layout.projectDirectory.dir("repo"))
+        }
+    }
+    return publishing
+}
+
+fun GradleBuildScriptInjectionContext.applyDefaultAndroidLibraryConfiguration() {
+    androidLibrary.apply {
+        compileSdk = 31
+        defaultConfig {
+            minSdk = 31
+            testInstrumentationRunner = "androidx.test.runner.AndroidJUnitRunner"
+        }
+        namespace = "org.jetbrains.kotlin.sample"
+    }
+
+    java.apply {
+        toolchain.languageVersion.set(JavaLanguageVersion.of(8))
+    }
+}

libraries/tools/kotlin-gradle-plugin-integration-tests/src/test/resources/testProject/base-kotlin-android-library/build.gradle.kts

@@ -0,0 +1,6 @@
+plugins {
+    id("com.android.library")
+    kotlin("android")
+}
+
+// To be filled by test code using buildScriptInjection API

libraries/tools/kotlin-gradle-plugin-integration-tests/src/test/resources/testProject/base-kotlin-android-library/src/main/AndroidManifest.xml

@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="utf-8"?>
+<manifest xmlns:android="http://schemas.android.com/apk/res/android">
+    <application>
+        <activity android:name=".KotlinActivity"/>
+    </application>
+</manifest>

libraries/tools/kotlin-gradle-plugin-integration-tests/src/test/resources/testProject/base-kotlin-android-library/src/main/kotlin/com/example/AppDummy.kt

@@ -0,0 +1,8 @@
+/*
+ * Copyright 2010-2018 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
+ */
+
+package com.example
+
+class AppDummy

libraries/tools/kotlin-gradle-plugin-integration-tests/src/test/resources/testProject/base-kotlin-android-library/src/main/kotlin/com/example/KotlinActivity.kt

@@ -0,0 +1,10 @@
+/*
+ * Copyright 2010-2018 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
+ */
+
+package com.example
+
+import android.app.Activity
+
+open class KotlinActivity : Activity()

libraries/tools/kotlin-gradle-plugin/api/all/kotlin-gradle-plugin.api

@@ -1166,6 +1166,11 @@ public final class org/jetbrains/kotlin/gradle/plugin/diagnostics/KotlinToolingD
 	public final fun invoke (Lorg/jetbrains/kotlin/gradle/plugin/KotlinSourceSet;)Lorg/jetbrains/kotlin/gradle/plugin/diagnostics/ToolingDiagnostic;
 }
 
+public final class org/jetbrains/kotlin/gradle/plugin/diagnostics/KotlinToolingDiagnostics$AndroidPublicationNotConfigured : org/jetbrains/kotlin/gradle/plugin/diagnostics/ToolingDiagnosticFactory {
+	public static final field INSTANCE Lorg/jetbrains/kotlin/gradle/plugin/diagnostics/KotlinToolingDiagnostics$AndroidPublicationNotConfigured;
+	public final fun invoke (Ljava/lang/String;Ljava/lang/String;)Lorg/jetbrains/kotlin/gradle/plugin/diagnostics/ToolingDiagnostic;
+}
+
 public final class org/jetbrains/kotlin/gradle/plugin/diagnostics/KotlinToolingDiagnostics$AndroidSourceSetLayoutV1Deprecation : org/jetbrains/kotlin/gradle/plugin/diagnostics/ToolingDiagnosticFactory {
 	public static final field INSTANCE Lorg/jetbrains/kotlin/gradle/plugin/diagnostics/KotlinToolingDiagnostics$AndroidSourceSetLayoutV1Deprecation;
 	public final fun invoke ()Lorg/jetbrains/kotlin/gradle/plugin/diagnostics/ToolingDiagnostic;

libraries/tools/kotlin-gradle-plugin/src/common/kotlin/org/jetbrains/kotlin/gradle/plugin/diagnostics/KotlinToolingDiagnostics.kt

@@ -10,7 +10,6 @@ import org.gradle.util.GradleVersion
 import org.jetbrains.kotlin.gradle.InternalKotlinGradlePluginApi
 import org.jetbrains.kotlin.gradle.PRESETS_DEPRECATION_MESSAGE_SUFFIX
 import org.jetbrains.kotlin.gradle.dsl.KotlinSourceSetConvention.isAccessedByKotlinSourceSetConventionAt
-import org.jetbrains.kotlin.gradle.dsl.NativeTargetShortcutTrace
 import org.jetbrains.kotlin.gradle.internal.KOTLIN_BUILD_TOOLS_API_IMPL
 import org.jetbrains.kotlin.gradle.internal.KOTLIN_MODULE_GROUP
 import org.jetbrains.kotlin.gradle.plugin.KotlinCompilation
@@ -1027,6 +1026,29 @@ object KotlinToolingDiagnostics {
             """.trimIndent()
         )
     }
+
+    object AndroidPublicationNotConfigured : ToolingDiagnosticFactory(WARNING) {
+        operator fun invoke(
+            componentName: String,
+            publicationName: String,
+        ): ToolingDiagnostic = build(
+            """
+                Android Publication '$publicationName' for variant '$componentName' was not configured properly:
+                
+                To avoid this warning, please create and configure Android publication variant with name '$componentName'.
+                Example:
+
+                    android {
+                        publishing {
+                            singleVariant("$componentName") {}
+                        }
+                    }
+                    
+                See https://kotl.in/oe70nr for more details
+            """.trimIndent(),
+            throwable = Throwable()
+        )
+    }
 }
 
 private fun String.indentLines(nSpaces: Int = 4, skipFirstLine: Boolean = true): String {

libraries/tools/kotlin-gradle-plugin/src/common/kotlin/org/jetbrains/kotlin/gradle/plugin/diagnostics/checkers/AndroidPublicationNotConfiguredChecker.kt

@@ -0,0 +1,51 @@
+/*
+ * Copyright 2010-2024 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
+ */
+
+package org.jetbrains.kotlin.gradle.plugin.diagnostics.checkers
+
+import org.gradle.api.publish.PublishingExtension
+import org.gradle.api.publish.maven.MavenPublication
+import org.jetbrains.kotlin.gradle.dsl.KotlinAndroidProjectExtension
+import org.jetbrains.kotlin.gradle.dsl.kotlinExtension
+import org.jetbrains.kotlin.gradle.plugin.KotlinPluginLifecycle.Stage
+import org.jetbrains.kotlin.gradle.plugin.await
+import org.jetbrains.kotlin.gradle.plugin.diagnostics.KotlinGradleProjectChecker
+import org.jetbrains.kotlin.gradle.plugin.diagnostics.KotlinGradleProjectCheckerContext
+import org.jetbrains.kotlin.gradle.plugin.diagnostics.KotlinToolingDiagnostics
+import org.jetbrains.kotlin.gradle.plugin.diagnostics.KotlinToolingDiagnosticsCollector
+import org.jetbrains.kotlin.gradle.plugin.internal.getComponentOrNull
+import org.jetbrains.kotlin.gradle.plugin.mpp.KotlinTargetSoftwareComponent
+import org.jetbrains.kotlin.gradle.utils.isPluginApplied
+
+internal object AndroidPublicationNotConfiguredChecker : KotlinGradleProjectChecker {
+    override suspend fun KotlinGradleProjectCheckerContext.runChecks(collector: KotlinToolingDiagnosticsCollector) {
+        // kotlin("android") is applied
+        if (project.kotlinExtension !is KotlinAndroidProjectExtension) return
+        project.isPluginApplied("com.android.library") || return
+        project.isPluginApplied("maven-publish") || return
+
+        // After this stage, all publications are created and configured
+        Stage.AfterFinaliseDsl.await()
+
+        val publishing = project.extensions.getByName("publishing") as PublishingExtension
+        publishing.publications.withType(MavenPublication::class.java).configureEach { publication ->
+            val component = publication.getComponentOrNull(project) ?: return@configureEach
+
+            // This is heuristic, but still reliable check.
+            // When all three plugins are applied AND user configured AGP's publications correctly,
+            // then neither of the components should be `KotlinTargetComponent`
+            if (component !is KotlinTargetSoftwareComponent) return@configureEach
+
+            collector.report(
+                project,
+                KotlinToolingDiagnostics.AndroidPublicationNotConfigured(
+                    // cast is needed to avoid ambiguity on getName()
+                    componentName = component.name,
+                    publicationName = publication.name,
+                )
+            )
+        }
+    }
+}

libraries/tools/kotlin-gradle-plugin/src/common/kotlin/org/jetbrains/kotlin/gradle/plugin/mpp/AbstractKotlinTarget.kt

@@ -96,7 +96,6 @@ abstract class AbstractKotlinTarget(
 
     /**
      * Returns, potentially not configured (e.g. without some usages), Gradle SoftwareComponent's for this target
-     * For final version of components use [awaitComponents]
      */
     override val components: Set<KotlinTargetSoftwareComponent> by lazy {
         kotlinComponents.map { kotlinComponent -> KotlinTargetSoftwareComponent(this, kotlinComponent) }.toSet()

libraries/tools/kotlin-gradle-plugin/src/common/kotlin/org/jetbrains/kotlin/gradle/plugin/registerKotlinPluginExtensions.kt

@@ -174,6 +174,7 @@ internal fun Project.registerKotlinPluginExtensions() {
         register(project, OverriddenKotlinNativeHomeChecker)
         register(project, ComposePluginSuggestApplyChecker)
         register(project, NativeVersionChecker)
+        register(project, AndroidPublicationNotConfiguredChecker)
 
         if (isMultiplatform) {
             register(project, MultipleSourceSetRootsInCompilationChecker)