Creating a Jar of test binaries - Gradle

Gradle Problem Overview

I'm using the latest version of Gradle (milestone 9), and I'm trying to figure out how to create a Jar of all test binaries.

From what I've found on the internet, the following should work:

task packageTests(type: Jar) {
  from sourceSets.test.classes
}

However I am getting a -

> Cannot get the value of write-only property 'classes' on source set > test.

What is the correct way of coding what I'm trying to achieve?

Is the property 'classes' somehow deprecated now ?

Changing sourceSets.test.classes to sourceSets.test.output fixes the problem.

In 2021 there is the Kotlin DSL now, so the latest answer looks like:

tasks.register<Jar>("packageTests") {
    from(sourceSets.test.get().output)
}

I do it with Gradle / Groovy like this:

  task testJar(type: Jar, dependsOn: testClasses) {
    classifier = 'test'
    from sourceSets.test.allSource
  }

Content Type	Original Author	Original Content on Stackoverflow
Question	vicsz	View Question on Stackoverflow
Solution 1 - Gradle	vicsz	View Answer on Stackoverflow
Solution 2 - Gradle	Mike Hearn	View Answer on Stackoverflow
Solution 3 - Gradle	Tomas Bjerre	View Answer on Stackoverflow