TestNG is a testing framework inspired from JUnit and NUnit but with new functionality to make it more powerful and easier to use. Features include:

TestNG is designed to cover all categories of tests: unit, functional, end-to-end, integration, etc...

The sections below illustrate using TestNG for the examples from Using Testing Frameworks with Groovy.

The Item Storer Example

Here is how you might use TestNG to integration test the Item Storer Example:

// require(groupId:'org.testng', artifactId:'testng', version='5.6')
import org.testng.annotations.*
import org.testng.TestNG
import org.testng.TestListenerAdapter

class StorerIntegrationTest {

    private storer

    @BeforeClass
    def setUp() {
        storer = new Storer()
    }

    private checkPersistAndReverse(value, reverseValue) {
        storer.put(value)
        assert value == storer.get()
        assert reverseValue == storer.getReverse()
    }

    @Test
    void shouldPersistAndReverseStrings() {
        checkPersistAndReverse 'hello', 'olleh'
    }

    @Test
    void shouldPersistAndReverseNumbers() {
        checkPersistAndReverse 123.456, -123.456
    }

    @Test
    void shouldPersistAndReverseLists() {
        checkPersistAndReverse([1, 3, 5], [5, 3, 1])
    }
}

def testng = new TestNG()
testng.setTestClasses(StorerIntegrationTest)
testng.addListener(new TestListenerAdapter())
testng.run()

You might also like to consider the special Groovy integration from the Test'N'Groove project which provides command-line runners and ant tasks for using TestNG with Groovy.