9.0.0-beta14 breaks when used with Gradle 8.14

[wolfs]

Expected and Results

I am trying to use the shadow plugin in a precompiled Kotlin build script in a Gradle 8.14 build. When upgrading from 9.0.0-beta13 to 9.0.0-beta14 I get the following error:

> Task :plugins:foo:compilePluginsBlocks FAILED
e: file:///my-home/.gradle/caches/modules-2/files-2.1/com.gradleup.shadow/shadow-gradle-plugin/9.0.0-beta14/7b7493640135a1855104bd4e2decfe58dc75e7f4/shadow-gradle-plugin-9.0.0-beta14.jar!/META-INF/shadow.kotlin_module Module was compiled with an incompatible version of Kotlin. The binary version of its metadata is 2.2.0, expected version is 2.0.0.

I suppose that is due to 5e44c138592c37b5b01a3bbd23cc7ad468f5297e. I suppose you need to set the Kotlin target correctly.

Related environment and versions

Gradle version: 8.14
shadow plugin version: 9.0.0-beta14

Reproduction steps

1. Add a precompiled Kotlin script plugin that applies the shadow plugin to an included build (or buildSrc) applying the shadow plugin
2. Try to run the build

Anything else?

No response

[Goooler]

I guess you want to say it's due to #1420? Also related to #1436.

[Goooler]

I already pinned the Kotlin configs. Anything I was missing?

shadow/build.gradle.kts

Lines 38 to 41 in b829b78

	// https://docs.gradle.org/current/userguide/compatibility.html#kotlin
	@Suppress("DEPRECATION") // TODO: bump apiVersion to 2.0 to match Gradle 9.0
	apiVersion = KotlinVersion.KOTLIN_1_8
	jvmTarget = JvmTarget.JVM_11

[wolfs]

After some searching, it might be the languageVersion = KotlinVersion.KOTLIN_1_8 is missing.

[Goooler]

I remembered that languageVersion defaults to apiVersion, maybe I'm wrong?

[Goooler]

Is there any Gradle Document that mentions this point? If missing, I suggest we can warn the plugin authors about it.