Test suites (testng.xml) in Selenium Java - Practice Problems & Coding Challenges

Challenge - 5 Problems

❓ Predict Output

intermediate

TestNG Suite Execution Order

Given the following testng.xml configuration, what is the order of test method execution?

Selenium Java

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE suite SYSTEM "https://testng.org/testng-1.0.dtd">
<suite name="Suite1">
  <test name="Test1">
    <classes>
      <class name="tests.SampleTest" />
    </classes>
  </test>
  <test name="Test2" preserve-order="false">
    <classes>
      <class name="tests.AnotherTest" />
    </classes>
  </test>
</suite>

A Tests run in parallel regardless of order

B All methods in AnotherTest run first in any order, then all methods in SampleTest run in defined order

C Methods from both classes run interleaved based on alphabetical order

D All methods in SampleTest run first in defined order, then all methods in AnotherTest run in any order

💡 Hint

Look at the preserve-order attribute and default behavior of TestNG suites.

By default, TestNG runs tests in the order they appear in the suite file. The first test 'Test1' runs all methods in SampleTest in defined order. The second test 'Test2' has preserve-order set to false, so methods in AnotherTest can run in any order, but only after Test1 completes.

❓ assertion

intermediate

Assertion on TestNG Suite Parallel Execution

Which assertion correctly verifies that tests defined in testng.xml run in parallel mode?

Selenium Java

<suite name="ParallelSuite" parallel="tests" thread-count="3">
  <test name="TestA">
    <classes>
      <class name="tests.TestA" />
    </classes>
  </test>
  <test name="TestB">
    <classes>
      <class name="tests.TestB" />
    </classes>
  </test>
</suite>

A Assert.assertEquals(suite.getParallel(), "tests");

B Assert.assertFalse(suite.isParallel());

C Assert.assertEquals(suite.getThreadCount(), 1);

D Assert.assertTrue(suite.isParallel());

💡 Hint

Check the attribute that controls parallel execution in TestNG suite.

The parallel attribute in the suite defines the parallel mode. Using suite.getParallel() returns the parallel mode string, which should be "tests" here. Other assertions either check wrong properties or wrong values.

🔧 Debug

advanced

Debugging Missing Test Execution in testng.xml

A tester notices that one test class is not running when executing the suite defined below. What is the most likely cause?

Selenium Java

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE suite SYSTEM "https://testng.org/testng-1.0.dtd">
<suite name="SuiteDebug">
  <test name="TestGroup">
    <groups>
      <run>
        <include name="smoke" />
      </run>
    </groups>
    <classes>
      <class name="tests.LoginTest" />
      <class name="tests.PaymentTest" />
    </classes>
  </test>
</suite>

A The <include> tag should be <exclude> to run smoke tests

B The <groups> tag is misplaced inside <test> instead of <suite>

C PaymentTest methods are not annotated with @Test(groups = "smoke")

D The suite name is missing the parallel attribute

💡 Hint

Check how TestNG runs tests filtered by groups.

When groups are included in the suite, only test methods annotated with those groups run. If PaymentTest methods lack the @Test(groups = "smoke") annotation, they will be skipped. The tag is correctly placed inside . Parallel attribute is unrelated to this issue.

❓ framework

advanced

Configuring TestNG Suite for Multiple Browsers

Which testng.xml snippet correctly configures two tests to run in parallel on Chrome and Firefox browsers using parameters?

A

<suite name="BrowserSuite">
  <test name="BrowserTest">
    <parameter name="browser" value="chrome,firefox" />
    <classes>
      <class name="tests.BrowserTest" />
    </classes>
  </test>
</suite>

B

<suite name="BrowserSuite" parallel="tests" thread-count="2">
  <test name="ChromeTest">
    <parameter name="browser" value="chrome" />
    <classes>
      <class name="tests.BrowserTest" />
    </classes>
  </test>
  <test name="FirefoxTest">
    <parameter name="browser" value="firefox" />
    <classes>
      <class name="tests.BrowserTest" />
    </classes>
  </test>
</suite>

C

<suite name="BrowserSuite" parallel="classes" thread-count="2">
  <test name="BrowserTest">
    <classes>
      <class name="tests.ChromeTest" />
      <class name="tests.FirefoxTest" />
    </classes>
  </test>
</suite>

D

<suite name="BrowserSuite" parallel="methods" thread-count="2">
  <test name="BrowserTest">
    <parameter name="browser" value="chrome" />
    <parameter name="browser" value="firefox" />
    <classes>
      <class name="tests.BrowserTest" />
    </classes>
  </test>
</suite>

💡 Hint

Parallel tests with different parameters require separate tags.

Option B defines two separate tags each with a different browser parameter and runs them in parallel. Option B passes both browsers as a single parameter value, which is not interpreted as two runs. Option B runs classes in parallel but does not pass parameters. Option B defines duplicate parameters in one test, which is invalid.

🧠 Conceptual

expert

Impact of preserve-order and parallel Attributes in testng.xml

Consider a TestNG suite with parallel="tests" and preserve-order="false" on a <test> tag. Which statement best describes the execution behavior?

A Tests run in parallel, and methods inside each test run in any order ignoring their declaration order

B Tests run sequentially, but methods inside each test run in parallel ignoring order

C Tests run in parallel, but methods inside each test run sequentially preserving order

D Tests and methods both run sequentially preserving order

💡 Hint

Understand how preserve-order affects method execution inside tests when parallel is enabled.

Setting parallel="tests" runs tests concurrently. preserve-order="false" on a test means methods inside that test do not preserve their declaration order and can run in any order. So tests run in parallel, and methods inside each test run unordered.

Practice

1. What is the main purpose of the testng.xml file in Selenium testing?

easy

A. To write the Selenium WebDriver code

B. To store test data like usernames and passwords

C. To group and organize test classes and methods to run together

D. To generate HTML reports after test execution

Solution

1. Step 1: Understand the role of testng.xml

   The testng.xml file is used to define which tests to run and how to organize them.

2. Step 2: Identify the main purpose

   It groups test classes and methods so they can be run together as a suite.

3. Final Answer:

   To group and organize test classes and methods to run together -> Option C

4. Quick Check:

   Test suite grouping = To group and organize test classes and methods to run together [OK]

Hint: Remember: testng.xml organizes tests to run as a group [OK]

Common Mistakes:

• Confusing testng.xml with test code files
• Thinking testng.xml stores test data
• Assuming testng.xml generates reports

2. Which of the following is the correct way to define a test suite in testng.xml?

easy

A.

B.

C.

D.

Solution

1. Step 1: Recall the correct XML structure for TestNG suites

   The root element is <suite>, inside it we define <test>, then <classes> and <class>.

2. Step 2: Match the options with correct structure

   correctly follows this order and syntax.

3. Final Answer:

   <suite name="MySuite"><test name="Test1"><classes><class name="TestClass"/></classes></test></suite> -> Option A

4. Quick Check:

   Suite > Test > Classes > Class = [OK]

Hint: Remember XML order: suite > test > classes > class [OK]

Common Mistakes:

• Swapping <suite> and <test> tags
• Placing <class> directly under <suite>
• Using wrong tag names or attributes

3. Given the following testng.xml snippet, what tests will run?

<suite name="Suite1" parallel="tests" thread-count="2">
  <test name="TestA">
    <classes>
      <class name="tests.LoginTest"/>
    </classes>
  </test>
  <test name="TestB">
    <classes>
      <class name="tests.PaymentTest"/>
    </classes>
  </test>
</suite>

medium

A. No tests run due to missing methods tag

B. Both LoginTest and PaymentTest run in parallel as separate tests

C. Tests run sequentially, LoginTest then PaymentTest

D. Only LoginTest runs because it is first

Solution

1. Step 1: Analyze the parallel attribute in <suite>

   The attribute parallel="tests" means each <test> runs in parallel threads.

2. Step 2: Identify the tests defined

   There are two tests: TestA with LoginTest class and TestB with PaymentTest class.

3. Final Answer:

   Both LoginTest and PaymentTest run in parallel as separate tests -> Option B

4. Quick Check:

   parallel="tests" runs tests simultaneously = Both LoginTest and PaymentTest run in parallel as separate tests [OK]

Hint: parallel="tests" runs each <test> in parallel [OK]

Common Mistakes:

• Assuming tests run sequentially despite parallel attribute
• Thinking <methods> tag is mandatory to run tests
• Confusing parallel="tests" with parallel="classes"

4. You have this testng.xml file but tests are not running:

<suite name="Suite1">
  <test name="Test1">
    <class name="TestClass">
    </class>
  </test>
</suite>

What is the likely problem?

medium

A. The <suite> tag must include thread-count

B. The <test> tag is missing the parallel attribute

C. The class name must include the package name

D. The <class> tag should be self-closing or empty, not with separate open and close tags

Solution

1. Step 1: Check the <class> tag syntax

   In TestNG XML, <class> should be self-closing like <class name="TestClass"/> or empty without content.

2. Step 2: Identify the error in the given XML

   The given XML uses separate open and close tags for <class> which is invalid and causes tests not to run.

3. Final Answer:

   The <class> tag should be self-closing or empty, not with separate open and close tags -> Option D

4. Quick Check:

   Use self-closing <class> tag = The <class> tag should be self-closing or empty, not with separate open and close tags [OK]

Hint: Use self-closing tag in testng.xml [OK]

Common Mistakes:

• Adding parallel attribute thinking it fixes syntax
• Forgetting package name but that doesn't stop tests
• Assuming thread-count is mandatory

5. You want to run two test classes LoginTest and PaymentTest in parallel but limit total threads to 1 in testng.xml. Which configuration achieves this?

hard

A.

B.

C.

D.

Solution

1. Step 1: Understand parallel and thread-count attributes

   Setting parallel="classes" runs test classes in parallel, and thread-count="1" limits to one thread, so classes run one at a time.

2. Step 2: Check options for matching configuration

   sets parallel to classes and thread-count to 1, matching the requirement.

3. Final Answer:

   Option A configuration runs classes in parallel but limits threads to 1 -> Option A

4. Quick Check:

   parallel="classes" + thread-count=1 = [OK]

Hint: parallel="classes" with thread-count=1 runs classes sequentially [OK]

Common Mistakes:

• Using parallel="tests" with thread-count > 1 runs multiple threads
• Omitting parallel attribute runs tests sequentially
• Confusing parallel="methods" with classes