From ed1bee6975abf8f1282bd194aa5e60374f54bdb8 Mon Sep 17 00:00:00 2001
From: Ilya Gorbunov <ilya.gorbunov@jetbrains.com>
Date: Sat, 21 Aug 2021 06:00:07 +0300
Subject: [PATCH] Setup Kotlin compilation of java 9 source sets consistently

Usually, java 9 source sets contain only module-info.java file, so
Kotlin compilation does not run because there are no .kt sources.
However, it can still start after some incremental changes and
thus it's important to have its JVM target configured consistently
with Java compilation of the same source set.
---
 buildSrc/src/main/kotlin/LibrariesCommon.kt | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/buildSrc/src/main/kotlin/LibrariesCommon.kt b/buildSrc/src/main/kotlin/LibrariesCommon.kt
index d3a97c61b5f..011f629af9a 100644
--- a/buildSrc/src/main/kotlin/LibrariesCommon.kt
+++ b/buildSrc/src/main/kotlin/LibrariesCommon.kt
@@ -11,6 +11,7 @@ import org.gradle.api.file.FileCollection
 import org.gradle.api.tasks.compile.JavaCompile
 import org.gradle.kotlin.dsl.get
 import org.gradle.process.CommandLineArgumentProvider
+import org.jetbrains.kotlin.gradle.tasks.KotlinCompile
 
 @JvmOverloads
 fun Project.configureJava9Compilation(
@@ -19,6 +20,11 @@ fun Project.configureJava9Compilation(
 ) {
     configurations["java9CompileClasspath"].extendsFrom(configurations["compileClasspath"])
 
+    tasks.named("compileJava9Kotlin", KotlinCompile::class.java) {
+        configureTaskToolchain(JdkMajorVersion.JDK_9)
+        kotlinOptions.jvmTarget = JdkMajorVersion.JDK_9.targetName
+    }
+
     tasks.named("compileJava9Java", JavaCompile::class.java) {
         dependsOn(moduleOutputs)