Remove support of Gradle 6.0 or less

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

@@ -253,8 +253,6 @@ private fun stdlibModuleForJvmCompilations(compilations: Iterable<KotlinCompilat
 
 //region kotlin-test
 internal fun configureKotlinTestDependency(project: Project) {
-    if (!isGradleVersionAtLeast(6, 0))
-        return
     if (!PropertiesProvider(project).kotlinTestInferJvmVariant)
         return
 

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

@@ -11,6 +11,9 @@ import org.gradle.api.Project
 import org.gradle.api.invocation.Gradle
 import org.gradle.api.logging.Logging
 import com.gradle.scan.plugin.BuildScanExtension
+import org.gradle.api.provider.Provider
+import org.gradle.build.event.BuildEventsListenerRegistry
+import org.gradle.tooling.events.OperationCompletionListener
 import org.jetbrains.kotlin.gradle.logging.kotlinDebug
 import org.jetbrains.kotlin.gradle.plugin.internal.state.TaskExecutionResults
 import org.jetbrains.kotlin.gradle.plugin.internal.state.TaskLoggers
@@ -23,7 +26,8 @@ import org.jetbrains.kotlin.gradle.utils.isConfigurationCacheAvailable
 
 //Support Gradle 6 and less. Move to
 internal class KotlinGradleBuildServices private constructor(
-    private val gradle: Gradle
+    private val gradle: Gradle,
+    private vararg val gradleListenerProviders: Provider<out OperationCompletionListener>
 ) : BuildAdapter() {
 
     companion object {
@@ -66,29 +70,32 @@ internal class KotlinGradleBuildServices private constructor(
         @Synchronized
         fun getInstance(project: Project, listenerRegistryHolder: BuildEventsListenerRegistryHolder): KotlinGradleBuildServices {
             val log = Logging.getLogger(KotlinGradleBuildServices::class.java)
-            val kotlinGradleListenerProvider: org.gradle.api.provider.Provider<KotlinGradleBuildListener> = project.provider {
+            val kotlinGradleListenerProvider: Provider<KotlinGradleBuildListener> = project.provider {
                 KotlinGradleBuildListener(KotlinGradleFinishBuildHandler())
             }
-            val kotlinGradleEsListenerProvider = project.provider {
-//                val listeners = project.objects.listProperty(ReportStatistics::class.java)
-//                    .value(listOf<ReportStatistics>(ReportStatisticsToElasticSearch))
-//                project.rootProject.extensions.findByType(BuildScanExtension::class.java)?.also { listeners.add(ReportStatisticsToBuildScan(it)) }
-//                KotlinBuildEsStatListener(project.rootProject.name, listeners.get())
 
-                val listeners = ArrayList<ReportStatistics>()
-                val buildScan = project.rootProject.extensions.findByName("buildScan")
-                buildScan?.also { listeners.add(ReportStatisticsToBuildScan(it as BuildScanExtension)) }
-                listeners.add(ReportStatisticsToElasticSearch)
-                KotlinBuildEsStatListener(project.rootProject.name, listeners)
+            val kotlinGradleEsListenerProvider = project.provider {
+                val listeners = project.rootProject.objects.listProperty(ReportStatistics::class.java)
+                    .value(listOf<ReportStatistics>(ReportStatisticsToElasticSearch))
+                project.rootProject.extensions.findByName("buildScan")
+                    ?.also { listeners.add(ReportStatisticsToBuildScan(it as BuildScanExtension)) }
+                KotlinBuildEsStatListener(project.rootProject.name, listeners.get())
             }
 
+
+            listenerRegistryHolder.listenerRegistry.onTaskCompletion(kotlinGradleListenerProvider)
+            listenerRegistryHolder.listenerRegistry.onTaskCompletion(kotlinGradleEsListenerProvider)
+
             if (instance != null) {
                 log.kotlinDebug(ALREADY_INITIALIZED_MESSAGE)
+//                instance!!.gradleListenerProviders.forEach { listenerRegistryHolder.listenerRegistry.onTaskCompletion(it) }
                 return instance!!
             }
 
             val gradle = project.gradle
-            val services = KotlinGradleBuildServices(gradle)
+            val services = KotlinGradleBuildServices(gradle, kotlinGradleListenerProvider, kotlinGradleEsListenerProvider)
+//            listenerRegistry.onTaskCompletion(kotlinGradleListenerProvider)
+//            listenerRegistry.onTaskCompletion(kotlinGradleEsListenerProvider)
             if (isConfigurationCacheAvailable(gradle)) {
                 listenerRegistryHolder.listenerRegistry!!.onTaskCompletion(kotlinGradleListenerProvider)
                 listenerRegistryHolder.listenerRegistry.onTaskCompletion(kotlinGradleEsListenerProvider)
@@ -97,6 +104,11 @@ internal class KotlinGradleBuildServices private constructor(
                 gradle.taskGraph.addTaskExecutionListener(kotlinGradleEsListenerProvider.get())
                 log.kotlinDebug(INIT_MESSAGE)
             }
+
+
+//            listenerRegistryHolder.listenerRegistry.onTaskCompletion(kotlinGradleListenerProvider)
+//            listenerRegistryHolder.listenerRegistry.onTaskCompletion(kotlinGradleEsListenerProvider)
+
             instance = services
 
             services.buildStarted()

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

@@ -73,7 +73,7 @@ class KotlinBuildEsStatListener(val projectName: String, val reportStatistics :
     }
 
     private fun availableForStat(taskPath: String): Boolean {
-        return taskPath.contains("compileKotlin")
+        return taskPath.contains("Kotlin")
     }
 
     override fun afterExecute(task: Task, taskState: TaskState) {

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

@@ -41,11 +41,7 @@ internal open class InspectClassesForMultiModuleIC : DefaultTask() {
     @get:Internal
     internal val fileTrees
         get() = sourceSetOutputClassesDir?.map {
-            if (isGradleVersionAtLeast(6, 0)) {
-                objects.fileTree().from(it).include("**/*.class")
-            } else {
-                project.fileTree(it).include("**/*.class")
-            }
+            objects.fileTree().from(it).include("**/*.class")
         }
 
     @get:Internal

libraries/tools/kotlin-gradle-plugin/src/main/kotlin/org/jetbrains/kotlin/gradle/testing/internal/conventions.kt

@@ -26,13 +26,9 @@ internal fun KotlinTest.configureConventions() {
     reports.configureConventions(project, name)
 
     fun binaryResultsDirDefault(): File = project.testResultsDir.resolve("$name/binary")
+    @Suppress("UnstableApiUsage")
+    binaryResultsDirectory.convention(project.layout.buildDirectory.dir(binaryResultsDirDefault().toRelativeString(project.buildDir)))
 
-    if (isGradleVersionAtLeast(5, 5)) {
-        @Suppress("UnstableApiUsage")
-        binaryResultsDirectory.convention(project.layout.buildDirectory.dir(binaryResultsDirDefault().toRelativeString(project.buildDir)))
-    } else {
-        conventionMapping.map("binResultsDir", ::binaryResultsDirDefault)
-    }
 }
 
 internal fun TestTaskReports.configureConventions(project: Project, name: String) {