From 56760412cb9c92fb32f1913b01e3401c3a5d5e60 Mon Sep 17 00:00:00 2001
From: James Rich <2199651+jamesarich@users.noreply.github.com>
Date: Sun, 28 Dec 2025 17:14:31 -0600
Subject: [PATCH] feat(build): Set JVM toolchain to 21 (#4090)

Signed-off-by: James Rich <2199651+jamesarich@users.noreply.github.com>
---
 .../meshtastic/buildlogic/KotlinAndroid.kt    | 28 +++----------------
 gradle/libs.versions.toml                     |  1 -
 2 files changed, 4 insertions(+), 25 deletions(-)

diff --git a/build-logic/convention/src/main/kotlin/org/meshtastic/buildlogic/KotlinAndroid.kt b/build-logic/convention/src/main/kotlin/org/meshtastic/buildlogic/KotlinAndroid.kt
index f40bf669e..dc8f9f055 100644
--- a/build-logic/convention/src/main/kotlin/org/meshtastic/buildlogic/KotlinAndroid.kt
+++ b/build-logic/convention/src/main/kotlin/org/meshtastic/buildlogic/KotlinAndroid.kt
@@ -20,15 +20,10 @@ package org.meshtastic.buildlogic
 import com.android.build.api.dsl.ApplicationExtension
 import com.android.build.api.dsl.CommonExtension
 import com.android.build.api.dsl.KotlinMultiplatformAndroidLibraryTarget
-import org.gradle.api.JavaVersion
 import org.gradle.api.Project
-import org.gradle.api.plugins.JavaPluginExtension
-import org.gradle.jvm.toolchain.JavaLanguageVersion
 import org.gradle.kotlin.dsl.configure
-import org.gradle.kotlin.dsl.dependencies
 import org.gradle.kotlin.dsl.findByType
 import org.gradle.kotlin.dsl.withType
-import org.jetbrains.kotlin.gradle.dsl.JvmTarget
 import org.jetbrains.kotlin.gradle.dsl.KotlinAndroidProjectExtension
 import org.jetbrains.kotlin.gradle.dsl.KotlinBaseExtension
 import org.jetbrains.kotlin.gradle.dsl.KotlinJvmProjectExtension
@@ -51,19 +46,9 @@ internal fun Project.configureKotlinAndroid(
                 commonExtension.defaultConfig.targetSdk = configProperties.getProperty("TARGET_SDK").toInt()
             }
         }
-
-        compileOptions.apply {
-            sourceCompatibility = JavaVersion.VERSION_21
-            targetCompatibility = JavaVersion.VERSION_21
-            isCoreLibraryDesugaringEnabled = true
-        }
     }
 
     configureKotlin<KotlinAndroidProjectExtension>()
-
-    dependencies {
-        "coreLibraryDesugaring"(libs.library("android.desugarJdkLibs"))
-    }
 }
 
 /**
@@ -93,14 +78,6 @@ internal fun Project.configureKotlinMultiplatform() {
  * Configure base Kotlin options for JVM (non-Android)
  */
 internal fun Project.configureKotlinJvm() {
-    extensions.configure<JavaPluginExtension> {
-        sourceCompatibility = JavaVersion.VERSION_21
-        targetCompatibility = JavaVersion.VERSION_21
-        toolchain {
-            languageVersion.set(JavaLanguageVersion.of(21))
-        }
-    }
-
     configureKotlin<KotlinJvmProjectExtension>()
 }
 
@@ -108,9 +85,12 @@ internal fun Project.configureKotlinJvm() {
  * Configure base Kotlin options
  */
 private inline fun <reified T : KotlinBaseExtension> Project.configureKotlin() {
+    extensions.configure<T> {
+        jvmToolchain(21)
+    }
+
     tasks.withType<KotlinCompile>().configureEach {
         compilerOptions {
-            jvmTarget.set(JvmTarget.JVM_21)
             allWarningsAsErrors.set(false)
             freeCompilerArgs.addAll(
                 // Enable experimental coroutines APIs, including Flow
diff --git a/gradle/libs.versions.toml b/gradle/libs.versions.toml
index 4ab053d9e..a90572c38 100644
--- a/gradle/libs.versions.toml
+++ b/gradle/libs.versions.toml
@@ -92,7 +92,6 @@ androidx-compose-ui-tooling = { module = "androidx.compose.ui:ui-tooling" }
 androidx-compose-ui-tooling-preview = { module = "androidx.compose.ui:ui-tooling-preview" }
 
 # Google
-android-desugarJdkLibs = { module = "com.android.tools:desugar_jdk_libs", version = "2.1.5" }
 firebase-analytics = { module = "com.google.firebase:firebase-analytics" }
 firebase-bom = { module = "com.google.firebase:firebase-bom", version = "34.7.0" }
 firebase-crashlytics = { module = "com.google.firebase:firebase-crashlytics" }