From 4bb2158cc04a40720d4fb90a76b9f5f6ebca15fd Mon Sep 17 00:00:00 2001
From: David Fairbrother <DavidFair@users.noreply.github.com>
Date: Sun, 5 Mar 2023 16:00:45 +0000
Subject: [PATCH] Use JDK toolchains to explicitly use JDK 17

Explicitly mark that we want version 17 of the JDK as the compiler. Previously
we implicitly relied on Gradle getting this right. This means devs and
CI will all use the same JDK explicitly rather than implicitly.

Pin the target JDK version in build.gradle.kts, this should apply to all
targets (including Kotlin) to version 1.8 to maintain compatibility with
older devices
---
 build.gradle.kts          | 7 +++++++
 buildSrc/build.gradle.kts | 6 ++++++
 2 files changed, 13 insertions(+)

diff --git a/build.gradle.kts b/build.gradle.kts
index 51c9bf4a4..db501b0b0 100644
--- a/build.gradle.kts
+++ b/build.gradle.kts
@@ -1,5 +1,6 @@
 plugins {
 	alias(libs.plugins.detekt)
+	java
 }
 
 buildscript {
@@ -9,6 +10,12 @@ buildscript {
 	}
 }
 
+java {
+	toolchain {
+		languageVersion.set(JavaLanguageVersion.of("17"))
+	}
+}
+
 subprojects {
 	// Configure linting
 	apply<io.gitlab.arturbosch.detekt.DetektPlugin>()
diff --git a/buildSrc/build.gradle.kts b/buildSrc/build.gradle.kts
index b6413e30c..499880d87 100644
--- a/buildSrc/build.gradle.kts
+++ b/buildSrc/build.gradle.kts
@@ -2,6 +2,12 @@ plugins {
 	`kotlin-dsl`
 }
 
+kotlin {
+	jvmToolchain {
+		languageVersion.set(JavaLanguageVersion.of("17"))
+	}
+}
+
 repositories {
 	mavenCentral()
 }