import org.akhikhl.gretty.FarmExtension

plugins {
    id("org.gretty") version "4.0.3"
}

// tag::delegateClosureOf[]
farms {
    farm("OldCoreWar", delegateClosureOf<FarmExtension> {
        // Config for the war here
    })
}

        val list = arrayListOf<Int>()
        delegateClosureOf<MutableList<Int>> { add(42) }.apply {
            delegate = list
            call()
        }
        assertEquals(42, list.first())
    }

    @Test
    fun `can use closure with a null delegate call`() {
        var passedIntoClosure: Any? = "Something non null"
        delegateClosureOf<Any?> { passedIntoClosure = this }.apply {
            delegate = null

 * configured Closure delegate.
 *
 * @param T the expected type of the delegate argument to the closure.
 * @param action the function to be adapted.
 *
 * @see [KotlinClosure1]
 */
fun <T> Any.delegateClosureOf(action: T.() -> Unit) =
    object : Closure<Unit>(this, this) {
        @Suppress("unused") // to be called dynamically by Groovy
        fun doCall() = uncheckedCast<T>(delegate).action()
    }


/**

.Use `delegateClosureOf<T> {}`
====
include::sample[dir="snippets/kotlinDsl/interoperability-delegate-closure-of/kotlin",files="build.gradle.kts[tags=delegateClosureOf]"]
====

There sometimes isn't a good way to tell, from looking at the source code, which version to use.
Usually, if you get a `NullPointerException` with `closureOf<T> {}`, using `delegateClosureOf<T> {}`
will resolve the problem.

Method <org.gradle.kotlin.dsl.GroovyInteroperabilityKt.delegateClosureOf(java.lang.Object, kotlin.jvm.functions.Function1)> has arguments/return type groovy.lang.Closure, kotlin.Unit that are not Gradle public API or primitive or built-in JDK classes or Kotlin classes in (GroovyInteroperability.kt:0)