Add separate Plugin Classpaths per compilation

Make them extend the common CP for sake of backward compatibility
^KT-45020 Fixed

libraries/tools/kotlin-gradle-plugin/src/functionalTest/kotlin/org/jetbrains/kotlin/gradle/mpp/CompilationSpecificPluginPath.kt

+/*
+ * Copyright 2010-2021 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.
+ */
+@file:Suppress("invisible_reference", "invisible_member", "FunctionName")
+
+package org.jetbrains.kotlin.gradle.mpp
+
+import org.gradle.api.Project
+import org.gradle.api.internal.project.ProjectInternal
+import org.gradle.api.provider.Provider
+import org.gradle.testfixtures.ProjectBuilder
+import org.jetbrains.kotlin.gradle.dsl.KotlinMultiplatformExtension
+import org.jetbrains.kotlin.gradle.dsl.kotlinExtension
+import org.jetbrains.kotlin.gradle.plugin.*
+import org.jetbrains.kotlin.gradle.tasks.KotlinCompile
+import kotlin.test.Test
+import kotlin.test.assertEquals
+import kotlin.test.assertNotNull
+import kotlin.test.assertTrue
+
+internal class CompilationSpecificPluginPath {
+    @Test
+    fun `each compilation should have its own plugin classpath`() {
+        val project = buildProjectWithMPP {
+            kotlin {
+                jvm("jvm1")
+                jvm("jvm2")
+                js("js") { browser() }
+            }
+        }
+
+        // Expect to see plugin classpath for each target compilation
+        listOf("jvm1", "jvm2", "js")
+            .map(String::capitalize)
+            .flatMap { listOf(pluginClassPathConfiguration(it, "main"), pluginClassPathConfiguration(it, "test")) }
+            .plus(pluginClassPathConfiguration("metadata", "main")) // and also one for metadata
+            .forEach { assertNotNull(project.configurations.findByName(it), "Configuration $it should exist") }
+    }
+
+    @Test
+    fun `kotlin plugin author can control plugin artifacts per compilation`() {
+        // Given platform-specific Kotlin plugins
+        class JvmOnly : FakeSubPlugin("jvmOnly", null, { target.platformType == KotlinPlatformType.jvm })
+        class JsOnly : FakeSubPlugin("jsOnly", null, { target.platformType == KotlinPlatformType.js })
+
+        // When apply them to a Kotlin MPP Project
+        val project = buildProjectWithMPP {
+            plugins.apply(JvmOnly::class.java)
+            plugins.apply(JsOnly::class.java)
+
+            kotlin {
+                jvm("desktop")
+                js("web", IR) {
+                    browser()
+                }
+            }
+        }
+        project.evaluate()
+
+        // Then each plugin classpath should have its own dependency
+        assertEquals(listOf("kotlin-scripting-compiler-embeddable", "jvmOnly"), project.subplugins("desktop"))
+        assertEquals(listOf("kotlin-scripting-compiler-embeddable", "jsOnly"), project.subplugins("web"))
+
+        // And each compilation task should have its own plugin classpath
+        val compileDesktop = project.tasks.getByName("compileKotlinDesktop") as KotlinCompile
+        val expectedConfig = project.configurations.getByName(pluginClassPathConfiguration("desktop", "main"))
+        assertEquals(expectedConfig, compileDesktop.pluginClasspath)
+    }
+
+    @Test
+    fun `native artifact should take precedence over regular artifact for native platform`() {
+        // Given common plugin but with native-specific artifact
+        class NativeSpecificPlugin : FakeSubPlugin("common", "native", { true })
+
+        val project = buildProjectWithMPP {
+            plugins.apply(NativeSpecificPlugin::class.java)
+
+            kotlin {
+                jvm()
+                linuxX64()
+            }
+        }
+        project.evaluate()
+
+        assertTrue("common" in project.subplugins("jvm"))
+        assertTrue("native" in project.subplugins("linuxX64"))
+        assertTrue("common" !in project.subplugins("linuxX64"))
+    }
+
+    @Test
+    fun `it should be possible to add common plugin classpath to all compilations except native`() {
+        // Given MPP project
+        val project = buildProjectWithMPP {
+            kotlin {
+                jvm()
+                js { browser() }
+                linuxX64("native")
+            }
+        }
+
+        // When adding a shared plugin to common Plugin Classpath
+        project.dependencies.add(PLUGIN_CLASSPATH_CONFIGURATION_NAME, "test:shared")
+        project.evaluate()
+
+        // Then ALL compilations should have shared plugin EXCEPT native
+        assertTrue("shared" in project.subplugins("jvm"))
+        assertTrue("shared" in project.subplugins("js"))
+        assertTrue("shared" in project.subplugins("js", "test"))
+        assertTrue("shared" in project.subplugins("metadata"))
+        assertTrue("shared" !in project.subplugins("native"))
+    }
+
+    @Test
+    fun `native compilations should have its own shared plugin classpath`() {
+        // Given MPP project
+        val project = buildProjectWithMPP {
+            kotlin {
+                jvm()
+                linuxX64("linux")
+                linuxX64("mac")
+            }
+        }
+
+        // When adding a shared plugin to native Plugin Classpath
+        project.dependencies.add(NATIVE_COMPILER_PLUGIN_CLASSPATH_CONFIGURATION_NAME, "test:shared")
+        project.evaluate()
+
+        // Then ALL native compilations should have shared plugin
+        assertTrue("shared" in project.subplugins("linux"))
+        assertTrue("shared" in project.subplugins("mac"))
+        assertTrue("shared" in project.subplugins("mac", "test"))
+
+        // And all non-native should not have it
+        assertTrue("shared" !in project.subplugins("metadata"))
+        assertTrue("shared" !in project.subplugins("jvm"))
+    }
+
+    private fun pluginClassPathConfiguration(target: String, compilation: String) =
+        "kotlinCompilerPluginClasspath${target.capitalize()}${compilation.capitalize()}"
+
+    private fun Project.subplugins(target: String, compilation: String = "main") = this
+        .configurations
+        .getByName(pluginClassPathConfiguration(target, compilation))
+        .allDependencies
+        .map { it.name }
+
+
+    private fun buildProjectWithMPP(code: Project.() -> Unit): ProjectInternal {
+        val project = ProjectBuilder.builder().build()
+        project.plugins.apply("kotlin-multiplatform")
+        project.code()
+        return project as ProjectInternal
+    }
+
+    private fun Project.kotlin(code: KotlinMultiplatformExtension.() -> Unit) {
+        val kotlin = project.kotlinExtension as KotlinMultiplatformExtension
+        kotlin.code()
+    }
+
+    private abstract class FakeSubPlugin(
+        val id: String,
+        val idNative: String? = null,
+        val isApplicablePredicate: KotlinCompilation<*>.() -> Boolean
+    ) : KotlinCompilerPluginSupportPlugin {
+        override fun isApplicable(kotlinCompilation: KotlinCompilation<*>): Boolean = kotlinCompilation.isApplicablePredicate()
+
+        override fun applyToCompilation(kotlinCompilation: KotlinCompilation<*>): Provider<List<SubpluginOption>> =
+            kotlinCompilation.target.project.provider { emptyList<SubpluginOption>() }
+
+        override fun getCompilerPluginId(): String = id
+
+        override fun getPluginArtifact(): SubpluginArtifact = SubpluginArtifact(
+            "test",
+            id
+        )
+
+        override fun getPluginArtifactForNative(): SubpluginArtifact? = idNative?.let {
+            SubpluginArtifact(
+                "test",
+                it
+            )
+        }
+    }
+}
\ No newline at end of file

libraries/tools/kotlin-gradle-plugin/src/main/kotlin/org/jetbrains/kotlin/gradle/internal/kapt/KaptWithKotlincTask.kt

@@ -21,7 +21,6 @@ import org.jetbrains.kotlin.gradle.internal.kapt.incremental.KaptIncrementalChan
 import org.jetbrains.kotlin.gradle.internal.tasks.allOutputFiles
 import org.jetbrains.kotlin.gradle.logging.GradleKotlinLogger
 import org.jetbrains.kotlin.gradle.logging.GradlePrintingMessageCollector
-import org.jetbrains.kotlin.gradle.plugin.PLUGIN_CLASSPATH_CONFIGURATION_NAME
 import org.jetbrains.kotlin.gradle.tasks.CompilerPluginOptions
 import org.jetbrains.kotlin.gradle.tasks.GradleCompileTaskProvider
 import org.jetbrains.kotlin.gradle.utils.getValue
@@ -35,14 +34,7 @@ abstract class KaptWithKotlincTask : KaptTask(), CompilerArgumentAwareWithInput<
 
     @get:Classpath
     @get:InputFiles
-    @Suppress("unused")
-    internal val kotlinTaskPluginClasspaths
-        get() = kotlinCompileTask.pluginClasspath
-
-    @get:Classpath
-    @get:InputFiles
-    val pluginClasspath: FileCollection
-        get() = project.configurations.getByName(PLUGIN_CLASSPATH_CONFIGURATION_NAME)
+    val pluginClasspath: FileCollection get() = kotlinCompileTask.pluginClasspath
 
     @get:Internal
     val taskProvider = GradleCompileTaskProvider(this)

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

@@ -564,9 +564,6 @@ internal abstract class AbstractKotlinPlugin(
 
             // Setup the consuming configurations:
             project.dependencies.attributesSchema.attribute(KotlinPlatformType.attribute)
-            kotlinTarget.compilations.all { compilation ->
-                AbstractKotlinTargetConfigurator.defineConfigurationsForCompilation(compilation)
-            }
 
             project.configurations.getByName("default").apply {
                 setupAsLocalTargetSpecificConfigurationIfSupported(kotlinTarget)
@@ -595,6 +592,7 @@ internal abstract class AbstractKotlinPlugin(
             buildSourceSetProcessor: (AbstractKotlinCompilation<*>) -> KotlinSourceSetProcessor<*>
         ) {
             kotlinTarget.compilations.all { compilation ->
+                AbstractKotlinTargetConfigurator.defineConfigurationsForCompilation(compilation)
                 buildSourceSetProcessor(compilation).run()
             }
         }

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

@@ -24,7 +24,6 @@ import org.gradle.api.internal.FeaturePreviews
 import org.gradle.api.logging.Logger
 import org.gradle.api.logging.Logging
 import org.gradle.tooling.provider.model.ToolingModelBuilderRegistry
-import org.jetbrains.kotlin.cli.common.CompilerSystemProperties
 import org.jetbrains.kotlin.gradle.dsl.*
 import org.jetbrains.kotlin.gradle.logging.kotlinDebug
 import org.jetbrains.kotlin.gradle.plugin.mpp.KotlinMetadataTarget

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

@@ -272,6 +272,17 @@ abstract class AbstractKotlinTargetConfigurator<KotlinTargetType : KotlinTarget>
             val target = compilation.target
             val configurations = target.project.configurations
 
+            val pluginConfiguration = configurations.maybeCreate(compilation.pluginConfigurationName).apply {
+                if (target.platformType == KotlinPlatformType.native) {
+                    extendsFrom(configurations.getByName(NATIVE_COMPILER_PLUGIN_CLASSPATH_CONFIGURATION_NAME))
+                } else {
+                    extendsFrom(target.project.commonKotlinPluginClasspath)
+                }
+                isVisible = false
+                isCanBeConsumed = false
+                description = "Kotlin compiler plugins for $compilation"
+            }
+
             val compileConfiguration = configurations.findByName(compilation.deprecatedCompileConfigurationName)?.apply {
                 isCanBeConsumed = false
                 setupAsLocalTargetSpecificConfigurationIfSupported(target)
@@ -493,3 +504,7 @@ fun Configuration.usesPlatformOf(target: KotlinTarget): Configuration {
     }
     return this
 }
+
+internal val Project.commonKotlinPluginClasspath get() = configurations.getByName(PLUGIN_CLASSPATH_CONFIGURATION_NAME)
+internal val KotlinCompilation<*>.pluginConfigurationName
+    get() = lowerCamelCaseName(PLUGIN_CLASSPATH_CONFIGURATION_NAME, target.disambiguationClassifier, compilationName)
\ No newline at end of file

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

@@ -66,12 +66,11 @@ class SubpluginEnvironment(
             val pluginId = subplugin.getCompilerPluginId()
             project.logger.kotlinDebug { "Loading subplugin $pluginId" }
 
-            subplugin.getPluginArtifact().let { artifact ->
-                project.addMavenDependency(PLUGIN_CLASSPATH_CONFIGURATION_NAME, artifact)
-            }
-
-            subplugin.getPluginArtifactForNative()?.let { artifact ->
-                project.addMavenDependency(NATIVE_COMPILER_PLUGIN_CLASSPATH_CONFIGURATION_NAME, artifact)
+            val nativeArtifact = subplugin.getPluginArtifactForNative()
+            if (nativeArtifact != null && kotlinCompilation.platformType == KotlinPlatformType.native) {
+                project.addMavenDependency(kotlinCompilation.pluginConfigurationName, nativeArtifact)
+            } else {
+                project.addMavenDependency(kotlinCompilation.pluginConfigurationName, subplugin.getPluginArtifact())
             }
 
             val subpluginOptionsProvider = subplugin.applyToCompilation(kotlinCompilation)

libraries/tools/kotlin-gradle-plugin/src/main/kotlin/org/jetbrains/kotlin/gradle/targets/native/KotlinNativeTargetConfigurator.kt

@@ -65,7 +65,9 @@ open class KotlinNativeTargetConfigurator<T : KotlinNativeTarget>(
                 .addSubpluginOptions(project, compilation)
 
             compilation.compileKotlinTaskProvider.configure {
-                it.compilerPluginClasspath = project.configurations.getByName(NATIVE_COMPILER_PLUGIN_CLASSPATH_CONFIGURATION_NAME)
+                it.compilerPluginClasspath = project
+                    .configurations
+                    .getByName(compilation.pluginConfigurationName)
             }
         }
     }

libraries/tools/kotlin-gradle-plugin/src/main/kotlin/org/jetbrains/kotlin/gradle/tasks/Tasks.kt

@@ -38,10 +38,8 @@ import org.jetbrains.kotlin.gradle.internal.*
 import org.jetbrains.kotlin.gradle.internal.tasks.TaskWithLocalState
 import org.jetbrains.kotlin.gradle.internal.tasks.allOutputFiles
 import org.jetbrains.kotlin.gradle.logging.*
+import org.jetbrains.kotlin.gradle.plugin.*
 import org.jetbrains.kotlin.gradle.plugin.COMPILER_CLASSPATH_CONFIGURATION_NAME
-import org.jetbrains.kotlin.gradle.plugin.KotlinMultiplatformPluginWrapper
-import org.jetbrains.kotlin.gradle.plugin.KotlinPlatformPluginBase
-import org.jetbrains.kotlin.gradle.plugin.PLUGIN_CLASSPATH_CONFIGURATION_NAME
 import org.jetbrains.kotlin.gradle.plugin.mpp.AbstractKotlinCompilation
 import org.jetbrains.kotlin.gradle.plugin.mpp.associateWithTransitiveClosure
 import org.jetbrains.kotlin.gradle.plugin.mpp.ownModuleName
@@ -219,7 +217,9 @@ abstract class AbstractKotlinCompile<T : CommonCompilerArguments>() : AbstractKo
 
     @get:InputFiles
     @get:Classpath
-    open val pluginClasspath: FileCollection = project.configurations.getByName(PLUGIN_CLASSPATH_CONFIGURATION_NAME)
+    open val pluginClasspath: FileCollection by project.provider {
+        project.configurations.getByName(taskData.compilation.pluginConfigurationName)
+    }
 
     @get:Internal
     internal val pluginOptions = CompilerPluginOptions()