Fix toolchain may fail to find tools.jar and false-fail the build.

This may happen when build itself is running on JDK9+ and toolchain
is set to <=JDK1.8. CompilerEnvironment gets 'tools.jar' from the
current Gradle Daemon JDK, but there was a check if exception should be
thrown that uses 'javaVersion' from toolchain provided JDK.

Additionally also fixed 'tools.jar' was not provided for
 'KotlinCompileWithWorkers' task.

^KT-47940 Fixed

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

@@ -671,6 +671,21 @@ class KotlinJavaToolchainTest : KGPBaseTest() {
         }
     }
 
+    @DisplayName("Toolchain should not make an exception when build is running on JDK 11, but toolchain is set to JDK 1.8")
+    @GradleTestVersions(minVersion = "6.7.1")
+    @GradleTest
+    internal fun shouldNotRaiseErrorOnJDK11withJDK1_8Toolchain(gradleVersion: GradleVersion) {
+        project(
+            projectName = "simple".fullProjectName,
+            gradleVersion = gradleVersion,
+            buildJdk = getJdk11().javaHome
+        ) {
+            useToolchainExtension(8)
+
+            build("assemble", forceOutput = true)
+        }
+    }
+
     private fun BuildResult.assertJdkHomeIsUsingJdk(
         javaexecPath: String
     ) = assertOutputContains("[KOTLIN] Kotlin compilation 'jdkHome' argument: $javaexecPath")

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

@@ -23,7 +23,7 @@ import kotlin.test.assertTrue
  *
  * @param [projectName] test project name in 'src/test/resources/testProject` directory.
  * @param [buildOptions] common Gradle build options
- * @param [buildJdk] path to JDK build should run with. *Note*: providing it disables debug!
+ * @param [buildJdk] path to JDK build should run with. *Note* Only append to 'gradle.properties'!
  */
 fun KGPBaseTest.project(
     projectName: String,
@@ -33,7 +33,7 @@ fun KGPBaseTest.project(
     addHeapDumpOptions: Boolean = true,
     enableGradleDebug: Boolean = false,
     projectPathAdditionalSuffix: String = "",
-    buildJdk: String? = null,
+    buildJdk: File? = null,
     test: TestProject.() -> Unit
 ): TestProject {
     val projectPath = setupProjectFromTestResources(
@@ -52,9 +52,6 @@ fun KGPBaseTest.project(
         .withProjectDir(projectPath.toFile())
         .withTestKitDir(testKitDir.toAbsolutePath().toFile())
         .withGradleVersion(gradleVersion.version)
-        .also {
-            if (buildJdk != null) it.withEnvironment(mapOf("JAVA_HOME" to buildJdk))
-        }
 
     val testProject = TestProject(
         gradleRunner,
@@ -65,6 +62,9 @@ fun KGPBaseTest.project(
         enableGradleDebug,
         forceOutput
     )
+
+    if (buildJdk != null) testProject.setupNonDefaultJdk(buildJdk)
+
     testProject.test()
     return testProject
 }
@@ -241,6 +241,16 @@ private fun Path.addDefaultBuildFiles() {
     }
 }
 
+private fun TestProject.setupNonDefaultJdk(pathToJdk: File) {
+    gradleProperties.modify {
+        """
+        |org.gradle.java.home=${pathToJdk.absolutePath.replace('\\', '/')}
+        |
+        |$it        
+        """.trimMargin()
+    }
+}
+
 @OptIn(ExperimentalPathApi::class)
 internal fun Path.enableAndroidSdk() {
     val androidSdk = KtTestUtil.findAndroidSdk()
@@ -326,11 +336,11 @@ private fun Path.addHeapDumpOptions() {
     if (existingJvmArgsLine.isEmpty()) {
         propertiesFile.writeText(
             """
-            # modified in addHeapDumpOptions
+            |# modified in addHeapDumpOptions
-            org.gradle.jvmargs=$heapDumpOutOfErrorStr $heapDumpPathStr
+            |org.gradle.jvmargs=$heapDumpOutOfErrorStr $heapDumpPathStr
-             
+            | 
-            $propertiesContent
+            |$propertiesContent
-            """.trimIndent()
+            """.trimMargin()
         )
     } else {
         val argsLine = existingJvmArgsLine.first()

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

@@ -75,14 +75,17 @@ internal abstract class DefaultKotlinJavaToolchain @Inject constructor(
         )
         .chainedFinalizeValueOnRead()
 
-    private fun getToolsJarFromJvm(jvmProvider: Provider<Jvm>): Provider<File?> {
+    private fun getToolsJarFromJvm(
+        jvmProvider: Provider<Jvm>,
+        javaVersionProvider: Provider<JavaVersion>
+    ): Provider<File?> {
         return objects
             .propertyWithConvention(
                 jvmProvider.flatMap { jvm ->
                     objects.propertyWithConvention(jvm.toolsJar)
                 }
             )
-            .orElse(javaVersion.flatMap {
+            .orElse(javaVersionProvider.flatMap {
                 if (it < JavaVersion.VERSION_1_9) {
                     throw GradleException(
                         "Kotlin could not find the required JDK tools in the Java installation. " +
@@ -95,10 +98,16 @@ internal abstract class DefaultKotlinJavaToolchain @Inject constructor(
     }
 
     @get:Internal
-    internal val jdkToolsJar: Provider<File?> = getToolsJarFromJvm(providedJvm)
+    internal val jdkToolsJar: Provider<File?> = getToolsJarFromJvm(providedJvm, javaVersion)
 
     @get:Internal
-    internal val currentJvmJdkToolsJar: Provider<File?> = getToolsJarFromJvm(currentJvm)
+    internal val currentJvmJdkToolsJar: Provider<File?> = getToolsJarFromJvm(
+        currentJvm,
+        currentJvm.map {
+            // Current JVM should always have java version
+            it.javaVersion!!
+        }
+    )
 
     final override val jdk: KotlinJavaToolchain.JdkSetter = DefaultJdkSetter(
         providedJvm,

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

@@ -776,16 +776,16 @@ internal abstract class KotlinCompileWithWorkers @Inject constructor(
     workerExecutor: WorkerExecutor
 ) : KotlinCompile(kotlinOptions) {
     override val compilerRunner: Provider<GradleCompilerRunner> =
-        objects.propertyWithConvention(
+        defaultKotlinJavaToolchain.flatMap { toolchain ->
-            gradleCompileTaskProvider.map {
+            objects.property(gradleCompileTaskProvider.map {
                 GradleCompilerRunnerWithWorkers(
                     it,
-                    null,
+                    toolchain.currentJvmJdkToolsJar.orNull,
                     normalizedKotlinDaemonJvmArguments.orNull,
                     workerExecutor
                 ) as GradleCompilerRunner
-            }
+            })
-        )
+        }
 }
 
 @CacheableTask