TestNG Testing Skill

When to Use

Use this skill when you need generates TestNG tests in Java with groups, data providers, parallel execution, XML suite configuration, and listeners. Use when user mentions "TestNG", "@DataProvider", "testng.xml", "groups". Triggers on: "TestNG", "@DataProvider", "testng.xml", "TestNG suite", "parallel tests Java".

Core Patterns

Basic Test with Groups

java
import org.testng.annotations.*;
import org.testng.Assert;

public class LoginTest {
    @BeforeMethod
    public void setUp() { /* setup */ }

    @Test(groups = "smoke")
    public void testLoginSuccess() {
        Assert.assertTrue(loginService.login("user@test.com", "password123"));
    }

    @Test(groups = "regression", dependsOnMethods = "testLoginSuccess")
    public void testAccessDashboard() {
        Assert.assertNotNull(dashboard.getContent());
    }

    @Test(expectedExceptions = AuthenticationException.class)
    public void testLoginInvalidPassword() {
        loginService.login("user@test.com", "wrong");
    }

    @AfterMethod
    public void tearDown() { /* cleanup */ }
}

Data Providers

java
@DataProvider(name = "loginData")
public Object[][] loginData() {
    return new Object[][] {
        {"admin@test.com", "admin123", true},
        {"user@test.com", "password", true},
        {"invalid@test.com", "wrong", false},
    };
}

@Test(dataProvider = "loginData")
public void testLogin(String email, String password, boolean expected) {
    Assert.assertEquals(loginService.login(email, password), expected);
}

TestNG XML Suite

xml
<!DOCTYPE suite SYSTEM "https://testng.org/testng-1.0.dtd">
<suite name="Regression" parallel="tests" thread-count="5">
  <test name="Smoke">
    <groups><run><include name="smoke"/></run></groups>
    <classes><class name="tests.LoginTest"/></classes>
  </test>
  <test name="Full">
    <groups><run><include name="regression"/><exclude name="flaky"/></run></groups>
    <packages><package name="tests.*"/></packages>
  </test>
</suite>

Parallel Execution

xml
<suite parallel="methods" thread-count="5">   <!-- Method level -->
<suite parallel="classes" thread-count="5">    <!-- Class level -->
<suite parallel="tests" thread-count="5">      <!-- Test level -->

Soft Assertions

java
SoftAssert soft = new SoftAssert();
soft.assertEquals(user.getName(), "Alice");
soft.assertEquals(user.getAge(), 25);
soft.assertTrue(user.isActive());
soft.assertAll();  // Reports all failures at once

Listeners

java
public class TestListener implements ITestListener {
    @Override public void onTestFailure(ITestResult result) {
        System.out.println("Failed: " + result.getName());
        // Take screenshot, log, etc.
    }
}

@Listeners(TestListener.class)
public class LoginTest { /* ... */ }

Lifecycle Annotations

@BeforeSuite → @BeforeTest → @BeforeClass → @BeforeMethod → @Test → @AfterMethod → @AfterClass → @AfterTest → @AfterSuite

Anti-Patterns

| Bad | Good | Why | |-----|------|-----| | dependsOnMethods everywhere | Independent tests | Cascading failures | | No groups | @Test(groups = "smoke") | Can't run subsets | | Hard-coded test data | @DataProvider | Reusable | | Priority ordering | Independent tests | Fragile |

Quick Reference

| Task | Command | |------|---------| | Run suite | mvn test -DsuiteXmlFile=testng.xml | | Run group | mvn test -Dgroups=smoke | | Run class | mvn test -Dtest=LoginTest | | Reports | test-output/index.html |

Deep Patterns → reference/playbook.md

| § | Section | Lines | |---|---------|-------| | 1 | Project Setup & Configuration | Maven + Surefire config | | 2 | Suite XML Configuration | Multi-env, parallel, groups | | 3 | BaseTest & Thread-Safe Driver | ThreadLocal, ConfigReader | | 4 | Data Providers (Advanced) | Excel, JSON, CSV, parallel, cross-class | | 5 | Factory Pattern | Cross-browser matrix | | 6 | Listeners (Production Suite) | Retry, screenshot, timing | | 7 | Soft Assertions & Dependencies | Groups, method deps | | 8 | Page Object Integration | PageFactory, fluent POs | | 9 | Parallel Execution Strategies | Method/class/test/mixed | | 10 | Reporting Integration | Allure, ExtentReports | | 11 | CI/CD Integration | GitHub Actions, Jenkins | | 12 | Debugging Quick-Reference | 12 common problems | | 13 | Best Practices Checklist | 14 items |

Limitations

• Use this skill only when the task clearly matches its upstream source and local project context.
• Verify commands, generated code, dependencies, credentials, and external service behavior before applying changes.
• Do not treat examples as a substitute for environment-specific tests, security review, or user approval for destructive or costly actions.