return suites;
    }

    public TestNGOptions includeGroups(String... includeGroups) {
        this.includeGroups.addAll(Arrays.asList(includeGroups));
        return this;
    }

    public TestNGOptions excludeGroups(String... excludeGroups) {
        this.excludeGroups.addAll(Arrays.asList(excludeGroups));
        return this;
    }

    public TestNGOptions useDefaultListeners() {

            testTask.getReports().getHtml(),
            objects.newInstance(TestNGOptions.class),
            testTask.getDryRun()
        );
    }

    private TestNGTestFramework(DefaultTestFilter filter, ObjectFactory objects, Factory<File> testTaskTemporaryDir, DirectoryReport htmlReport, TestNGOptions options, Provider<Boolean> dryRun) {
        this.filter = filter;
        this.objects = objects;

        when:
        testngOptions.includeGroups(groups)

        then:
        testngOptions.includeGroups == groups as Set
        testngOptions.excludeGroups.empty
    }

    def testExcludeGroups() {
        when:
        testngOptions.excludeGroups(groups)

        then:
        testngOptions.excludeGroups == groups as Set
        testngOptions.includeGroups.empty
    }

repositories {
    mavenCentral()
}

dependencies {
    testImplementation("org.testng:testng:6.3.1")
}

// tag::test-config[]
tasks.named<Test>("test") {
    useTestNG {
        val options = this as TestNGOptions
        options.excludeGroups("integrationTests")
        options.includeGroups("unitTests")
    }
}

import org.gradle.api.internal.tasks.testing.filter.DefaultTestFilter
import org.gradle.api.model.ObjectFactory
import org.gradle.api.tasks.testing.Test
import org.gradle.api.tasks.testing.testng.TestNGOptions
import org.gradle.internal.actor.ActorFactory
import org.gradle.internal.id.IdGenerator
import org.gradle.internal.time.Clock
import org.gradle.testfixtures.ProjectBuilder
import org.gradle.util.TestUtil

                && junitPlatformOptions.getExcludeTags().isEmpty();
        } else if (TestNGOptions.class.isAssignableFrom(frameworkOptions.getClass())) {
            TestNGOptions testNGOptions = (TestNGOptions) frameworkOptions;
            return testNGOptions.getIncludeGroups().isEmpty()
                && testNGOptions.getExcludeGroups().isEmpty();
        } else {

                        // set a system property for the test JVM(s)
                        systemProperty("some.prop", "value")
                        options { // <3>
                            val options = this as TestNGOptions
                            options.preserveOrder = true
                        }
                    }
                }
            }
        }
    }
}

Method <org.gradle.api.tasks.testing.testng.TestNGOptions.getConfigFailurePolicy()> does not have raw return type assignable to org.gradle.api.provider.Property in (TestNGOptions.java:0)
Method <org.gradle.api.tasks.testing.testng.TestNGOptions.getExcludeGroups()> does not have raw return type assignable to org.gradle.api.provider.Property in (TestNGOptions.java:0)

Accessors for org.gradle.api.tasks.javadoc.Javadoc.maxMemory don't use symmetrical @Nullable
Accessors for org.gradle.api.tasks.testing.Test.forkEvery don't use symmetrical @Nullable
Accessors for org.gradle.api.tasks.testing.testng.TestNGOptions.parallel don't use symmetrical @Nullable
Accessors for org.gradle.caching.http.HttpBuildCache.url don't use symmetrical @Nullable

/gradle/api/tasks/testing/junit/JUnitOptions.html[JUnitOptions], link:{javadocPath}/org/gradle/api/tasks/testing/junitplatform/JUnitPlatformOptions.html[JUnitPlatformOptions] and link:{javadocPath}/org/gradle/api/tasks/testing/testng/TestNGOptions.html[TestNGOptions]. We cover a significant number of them in the rest of the chapter.

If you want to set up your own `Test` task with its own set of test classes, then the easiest approach is to create your own source set and `Test` task instance,...