[Gradle, JS] Make MultiplePluginDeclarationDetector compatible w/ conf cache

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

@@ -0,0 +1,36 @@
+/*
+ * 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.
+ */
+
+package org.jetbrains.kotlin.gradle.plugin
+
+import org.gradle.api.invocation.Gradle
+import org.gradle.api.services.BuildService
+import org.gradle.api.services.BuildServiceParameters
+
+abstract class BuildFinishedListenerService : BuildService<BuildServiceParameters.None>, AutoCloseable {
+    private val actionsOnClose = mutableListOf<() -> Unit>()
+
+    fun onClose(action: () -> Unit) {
+        actionsOnClose.add(action)
+    }
+
+    override fun close() {
+        for (action in actionsOnClose) {
+            action()
+        }
+        actionsOnClose.clear()
+    }
+
+    companion object {
+        fun getInstance(gradle: Gradle): BuildFinishedListenerService {
+            // Use class loader hashcode in case there are multiple class loaders in the same build
+            return gradle.sharedServices
+                .registerIfAbsent(
+                    "build-finished-listener_${BuildFinishedListenerService::class.java.classLoader.hashCode()}",
+                    BuildFinishedListenerService::class.java
+                ) {}.get()
+        }
+    }
+}

libraries/tools/kotlin-gradle-plugin/src/main/kotlin/org/jetbrains/kotlin/gradle/targets/js/MultiplePluginDeclarationDetector.kt

@@ -7,8 +7,10 @@ package org.jetbrains.kotlin.gradle.targets.js
 
 import org.gradle.api.Project
 import org.gradle.api.invocation.Gradle
+import org.jetbrains.kotlin.gradle.plugin.BuildFinishedListenerService
 import org.jetbrains.kotlin.gradle.plugin.KotlinPluginInMultipleProjectsHolder
 import org.jetbrains.kotlin.gradle.plugin.MULTIPLE_KOTLIN_PLUGINS_LOADED_WARNING
+import org.jetbrains.kotlin.gradle.utils.isConfigurationCacheAvailable
 
 internal class MultiplePluginDeclarationDetector
 private constructor() {
@@ -40,9 +42,12 @@ private constructor() {
 
             val detector = MultiplePluginDeclarationDetector()
             instance = detector
-//            gradle.buildFinished {
+
-//                instance = null
+            if (isConfigurationCacheAvailable(gradle)) {
-//            }
+                BuildFinishedListenerService.getInstance(gradle).onClose { instance = null }
+            } else {
+                gradle.buildFinished { instance = null }
+            }
 
             return detector
         }
@@ -51,4 +56,4 @@ private constructor() {
             getInstance(project.gradle).detect(project)
         }
     }
-}
+}