Model mapping: support Android targets

libraries/tools/kotlin-gradle-plugin/src/main/kotlin/org/jetbrains/kotlin/gradle/plugin/mpp/CompilationDetails.kt

@@ -330,7 +330,7 @@ open class DefaultCompilationDetails<T : KotlinCommonOptions>(
     }
 }
 
-internal open class DefaultCompilationDetailsWithRuntime<T : KotlinCommonOptions>(
+open class DefaultCompilationDetailsWithRuntime<T : KotlinCommonOptions>(
     target: KotlinTarget,
     compilationPurpose: String,
     createKotlinOptions: DefaultCompilationDetails<*>.() -> T
@@ -517,18 +517,19 @@ internal class WithJavaCompilationDetails<T : KotlinCommonOptions>(
     }
 }
 
-internal class AndroidCompilationDetails(
+class AndroidCompilationDetails(
     target: KotlinTarget,
     compilationPurpose: String,
+    /** Workaround mutual creation order: a compilation is not added to the target's compilations collection until some point, pass it here */
+    private val getCompilationInstance: () -> KotlinJvmAndroidCompilation
 ) : DefaultCompilationDetailsWithRuntime<KotlinJvmOptions>(
     target,
     compilationPurpose,
     { KotlinJvmOptionsImpl() }
 ) {
-    override val compilation: KotlinJvmAndroidCompilation
-        get() = super.compilation as KotlinJvmAndroidCompilation
+    override val compilation: KotlinJvmAndroidCompilation get() = getCompilationInstance()
 
-    val androidVariant = compilation.androidVariant
+    val androidVariant get() = compilation.androidVariant
 
     override val friendArtifacts: FileCollection
         get() = target.project.files(super.friendArtifacts, compilation.testedVariantArtifacts)

libraries/tools/kotlin-gradle-plugin/src/main/kotlin/org/jetbrains/kotlin/gradle/plugin/sources/kpm/FragmentMappedKotlinSourceSet.kt

@@ -19,11 +19,12 @@ import org.jetbrains.kotlin.gradle.plugin.mpp.pm20.util.unambiguousNameInProject
 import org.jetbrains.kotlin.gradle.plugin.sources.createDefaultSourceDirectorySet
 
 class FragmentMappedKotlinSourceSet(
+    private val sourceSetName: String,
     private val project: Project,
     internal val underlyingFragment: KotlinGradleFragment
 ) : KotlinSourceSet {
     val displayName: String
-        get() = underlyingFragment.unambiguousNameInProject
+        get() = sourceSetName
 
     override val apiConfigurationName: String get() = underlyingFragment.apiConfigurationName
     override val implementationConfigurationName: String get() = underlyingFragment.implementationConfigurationName

libraries/tools/kotlin-gradle-plugin/src/main/kotlin/org/jetbrains/kotlin/gradle/plugin/sources/kpm/FragmentMappedKotlinSourceSetFactory.kt

@@ -21,6 +21,6 @@ class FragmentMappedKotlinSourceSetFactory constructor(private val project: Proj
         val modules = project.kpmModules
         val fragment = modules.maybeCreate(moduleName).fragments.maybeCreate(fragmentName)
         /** TODO setup JS-specific attributes similar to [org.jetbrains.kotlin.gradle.plugin.sources.DefaultKotlinSourceSetFactory]*/
-        return FragmentMappedKotlinSourceSet(project, fragment)
+        return FragmentMappedKotlinSourceSet(name, project, fragment)
     }
 }

libraries/tools/kotlin-gradle-plugin/src/main/kotlin/org/jetbrains/kotlin/gradle/plugin/sources/kpm/SourceSetMappedFragmentLocator.kt

@@ -9,6 +9,9 @@ import org.gradle.api.Project
 import org.jetbrains.kotlin.gradle.dsl.*
 import org.jetbrains.kotlin.gradle.dsl.pm20Extension
 import org.jetbrains.kotlin.gradle.dsl.topLevelExtensionOrNull
+import org.jetbrains.kotlin.gradle.plugin.mpp.KotlinAndroidTarget
+import org.jetbrains.kotlin.gradle.plugin.mpp.KotlinAndroidTargetPreset
+import org.jetbrains.kotlin.gradle.plugin.mpp.pm20.KotlinGradleModule
 import org.jetbrains.kotlin.gradle.plugin.mpp.pm20.kpmModules
 
 interface SourceSetMappedFragmentLocator {
@@ -34,16 +37,41 @@ private class MultiplatformSourceSetMappedFragmentLocator : SourceSetMappedFragm
     override fun locateFragmentForSourceSet(project: Project, sourceSetName: String): SourceSetMappedFragmentLocator.FragmentLocation? {
         val camelCaseParts = sourceSetName.camelCaseParts()
         if (camelCaseParts.size < 2) {
-            return null
+            SourceSetMappedFragmentLocator.FragmentLocation(KotlinGradleModule.MAIN_MODULE_NAME, sourceSetName)
         }
+
+        val androidTarget = when (val ext = project.topLevelExtension) {
+            is KotlinAndroidProjectExtension -> ext.target
+            is KotlinMultiplatformExtension ->
+                ext.targets.withType(KotlinAndroidTarget::class.java).singleOrNull()
+                    ?: ext.presets.withType(KotlinAndroidTargetPreset::class.java).single().targetUnderConstruction
+            else -> null
+        }
+
         val candidateModuleNames = (1..camelCaseParts.size).asSequence().map { camelCaseParts.takeLast(it).joinToString("").decapitalize() }
+
         val moduleName =
-            candidateModuleNames.firstOrNull { project.kpmModules.findByName(it) != null } ?: candidateModuleNames.first()
-        val fragmentName = sourceSetName.dropLast(moduleName.length)
+            run {
+                if (androidTarget != null && sourceSetName.startsWith(androidTarget.name))
+                    androidSourceSetModuleName(androidTarget.name, sourceSetName)
+                else null
+            } ?: candidateModuleNames.firstOrNull { project.kpmModules.findByName(it) != null }
+            ?: KotlinGradleModule.MAIN_MODULE_NAME
+
+        val fragmentName =
+            if (sourceSetName.endsWith(moduleName, ignoreCase = true)) sourceSetName.dropLast(moduleName.length) else sourceSetName
 
         return SourceSetMappedFragmentLocator.FragmentLocation(moduleName, fragmentName)
     }
 
+    private fun androidSourceSetModuleName(targetName: String, sourceSetName: String): String? {
+        val compilationName = sourceSetName.removePrefix(targetName).takeIf { it != sourceSetName } ?: return null
+        return when {
+            "Test" in compilationName -> "test"
+            else -> KotlinGradleModule.MAIN_MODULE_NAME
+        }
+    }
+
     private fun String.camelCaseParts(): List<String> {
         val capitalizedMatches = Regex("[A-Z][^A-Z]*").findAll(this).toList()
         val firstNonCapitalizedWord = capitalizedMatches.firstOrNull()?.let { substring(it.range.first) } ?: this

libraries/tools/kotlin-gradle-plugin/src/main/kotlin/org/jetbrains/kotlin/gradle/targets/android/KotlinAndroidTargetPreset.kt

@@ -9,6 +9,9 @@ package org.jetbrains.kotlin.gradle.plugin.mpp
 import org.gradle.api.Project
 import org.jetbrains.kotlin.gradle.plugin.KotlinAndroidPlugin.Companion.dynamicallyApplyWhenAndroidPluginIsApplied
 import org.jetbrains.kotlin.gradle.plugin.KotlinTargetPreset
+import org.jetbrains.kotlin.gradle.plugin.mpp.pm20.PublicationRegistrationMode
+import org.jetbrains.kotlin.gradle.plugin.mpp.pm20.hasKpmModel
+import org.jetbrains.kotlin.gradle.plugin.mpp.pm20.mapTargetCompilationsToKpmVariants
 
 class KotlinAndroidTargetPreset(
     private val project: Project
@@ -20,12 +23,23 @@ class KotlinAndroidTargetPreset(
         val result = KotlinAndroidTarget(name, project).apply {
             disambiguationClassifier = name
             preset = this@KotlinAndroidTargetPreset
+            targetUnderConstruction = this
         }
 
         project.dynamicallyApplyWhenAndroidPluginIsApplied({ result })
+
+        if (project.hasKpmModel) {
+            mapTargetCompilationsToKpmVariants(result, PublicationRegistrationMode.AFTER_EVALUATE)
+        }
+
+        targetUnderConstruction = null
+
         return result
     }
 
+    /** This is a way to check if there's an Android target being configured now despite it not being added to the `kotlin.targets` yet */
+    internal var targetUnderConstruction: KotlinAndroidTarget? = null
+
     companion object {
         const val PRESET_NAME = "android"
     }

libraries/tools/kotlin-gradle-plugin/src/main/kotlin/org/jetbrains/kotlin/gradle/targets/jvm/KotlinJvmAndroidCompilation.kt

@@ -18,9 +18,8 @@ import org.jetbrains.kotlin.gradle.plugin.getJavaTaskProvider
 import org.jetbrains.kotlin.gradle.plugin.getTestedVariantData
 
 class KotlinJvmAndroidCompilation(
-    target: KotlinAndroidTarget,
-    name: String
-) : AbstractKotlinCompilationToRunnableFiles<KotlinJvmOptions>(AndroidCompilationDetails(target, name)) {
+    compilationDetails: AndroidCompilationDetails
+) : AbstractKotlinCompilationToRunnableFiles<KotlinJvmOptions>(compilationDetails) {
 
     lateinit var androidVariant: BaseVariant
         internal set

libraries/tools/kotlin-gradle-plugin/src/main/kotlin/org/jetbrains/kotlin/gradle/targets/jvm/KotlinJvmAndroidCompilationFactory.kt

@@ -16,6 +16,10 @@ class KotlinJvmAndroidCompilationFactory(
     override val itemClass: Class<KotlinJvmAndroidCompilation>
         get() = KotlinJvmAndroidCompilation::class.java
 
-    override fun create(name: String): KotlinJvmAndroidCompilation =
-        KotlinJvmAndroidCompilation(target, name)
+    override fun create(name: String): KotlinJvmAndroidCompilation {
+        lateinit var result: KotlinJvmAndroidCompilation
+        val details = AndroidCompilationDetails(target, name) { result }
+        result = KotlinJvmAndroidCompilation(details)
+        return result
+    }
 }