Conftest for shared fixtures in Selenium Python - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is the purpose of a conftest.py file in pytest?

The conftest.py file is used to define shared fixtures and hooks that can be used across multiple test files without importing them explicitly.

beginner

How do you define a fixture in conftest.py for Selenium WebDriver?

You define a function with the @pytest.fixture decorator that initializes the WebDriver, yields it for use in tests, and then quits the driver after tests finish.

beginner

Why is it better to put Selenium WebDriver setup in conftest.py instead of each test file?

Putting WebDriver setup in conftest.py avoids repeating code, makes tests cleaner, and ensures consistent setup and teardown across all tests.

intermediate

What does the scope parameter in a pytest fixture control?

The scope parameter controls how often the fixture is invoked. For example, scope='function' runs before each test, scope='session' runs once per test session.

beginner

How can you use a fixture from conftest.py in your test function?

Simply add the fixture name as a parameter to your test function. Pytest will automatically find and inject the fixture from conftest.py.

What is the main benefit of using conftest.py for fixtures?

A To run tests in parallel automatically

B To write test cases faster

C To avoid using Selenium WebDriver

D To share fixtures across multiple test files without imports

The conftest.py file allows sharing fixtures across test files without explicit imports.

Which decorator is used to define a fixture in pytest?

A @pytest.test

B @pytest.fixture

C @pytest.setup

D @pytest.driver

Fixtures in pytest are defined using the @pytest.fixture decorator.

If you want a Selenium WebDriver fixture to run once per test session, which scope should you use?

A function

B module

C session

D class

Using scope='session' makes the fixture run once for the entire test session.

How do you ensure the WebDriver quits after a test using a fixture?

A Use yield in the fixture and call driver.quit() after yield

B Call driver.quit() inside the test

C Do nothing, it quits automatically

D Use a global variable

Using yield in the fixture allows setup before yield and teardown (like driver.quit()) after yield.

How do you use a fixture named browser in your test function?

A Add <code>browser</code> as a parameter to the test function

B Import browser and call it

C Call <code>pytest.browser()</code>

D Use <code>self.browser</code> inside the test

Pytest injects fixtures by matching parameter names in test functions.

Explain how to create and use a Selenium WebDriver fixture in conftest.py.

Think about setup and teardown using yield.

Describe the benefits of using conftest.py for shared fixtures in Selenium testing.

Consider how shared setup helps in many tests.

Practice

1. What is the main purpose of a conftest.py file in Selenium Python testing?

easy

A. To hold shared fixtures for setup and cleanup across multiple test files

B. To store test data in JSON format

C. To define Selenium WebDriver locators

D. To write test cases directly

Solution

1. Step 1: Understand the role of conftest.py

   The conftest.py file is used to define fixtures that can be shared across multiple test files for setup and cleanup tasks.

2. Step 2: Differentiate from other files

   It does not store test data, locators, or test cases directly but provides reusable setup code like browser initialization.

3. Final Answer:

   To hold shared fixtures for setup and cleanup across multiple test files -> Option A

4. Quick Check:

   conftest.py = shared fixtures [OK]

Hint: Remember: conftest.py shares setup code across tests [OK]

Common Mistakes:

• Confusing conftest.py with test case files
• Thinking conftest.py stores test data
• Using conftest.py to write test assertions

2. Which of the following is the correct way to declare a fixture in conftest.py using pytest?

easy

A. def browser(): yield webdriver.Chrome()

B. @pytest.fixture
def browser(): yield webdriver.Chrome()

C. fixture browser(): yield webdriver.Chrome()

D. @fixture def browser(): return webdriver.Chrome()

Solution

1. Step 1: Identify correct fixture decorator usage

   pytest fixtures require the @pytest.fixture decorator above the function to mark it as a fixture.

2. Step 2: Check syntax correctness

   @pytest.fixture def browser(): yield webdriver.Chrome() correctly uses @pytest.fixture and a generator with yield to provide the resource.

3. Final Answer:

   @pytest.fixture\ndef browser(): yield webdriver.Chrome() -> Option B

4. Quick Check:

   Use @pytest.fixture decorator [OK]

Hint: Always prefix fixture functions with @pytest.fixture [OK]

Common Mistakes:

• Omitting @pytest.fixture decorator
• Using wrong decorator name like @fixture
• Not using yield for setup/teardown

3. Given this fixture in conftest.py:

@pytest.fixture
def browser():
    driver = webdriver.Chrome()
    yield driver
    driver.quit()

What happens when a test uses this fixture?

medium

A. The browser never opens because yield is missing

B. The browser opens and closes immediately before the test runs

C. The browser opens but never closes

D. The browser opens before the test and closes after the test finishes

Solution

1. Step 1: Understand yield in fixture

   The yield statement pauses the fixture, providing the driver to the test, then resumes after the test to run cleanup.

2. Step 2: Analyze setup and teardown

   Driver is created before yield (browser opens), and driver.quit() runs after test finishes (browser closes).

3. Final Answer:

   The browser opens before the test and closes after the test finishes -> Option D

4. Quick Check:

   yield = setup before, cleanup after [OK]

Hint: yield splits setup and teardown in fixtures [OK]

Common Mistakes:

• Thinking yield closes browser immediately
• Forgetting driver.quit() after yield
• Assuming browser stays open forever

4. You wrote this fixture in conftest.py:

@pytest.fixture
def browser():
    driver = webdriver.Chrome()
    return driver
    driver.quit()

What is the problem with this fixture?

medium

A. driver.quit() is never called, so browser stays open after tests

B. Syntax error because return and yield cannot be used together

C. Fixture will not provide the driver to tests

D. driver.quit() runs before driver is created

Solution

1. Step 1: Analyze return and driver.quit() placement

   Since return exits the function immediately, driver.quit() after it never runs.

2. Step 2: Understand impact on browser lifecycle

   Without driver.quit(), the browser stays open after tests, causing resource leaks.

3. Final Answer:

   driver.quit() is never called, so browser stays open after tests -> Option A

4. Quick Check:

   return ends function before cleanup [OK]

Hint: Use yield, not return, to ensure cleanup runs [OK]

Common Mistakes:

• Placing driver.quit() after return
• Using return instead of yield for fixtures
• Expecting cleanup code after return to run

5. You want to share a browser fixture in conftest.py that opens Chrome once per test session and closes it after all tests finish. Which fixture scope and code is correct?

hard

A. @pytest.fixture(scope='function')
def browser():
driver = webdriver.Chrome()
yield driver
driver.quit()

B. @pytest.fixture(scope='module')
def browser():
driver = webdriver.Chrome()
driver.quit()
yield driver

C. @pytest.fixture(scope='session')
def browser():
driver = webdriver.Chrome()
yield driver
driver.quit()

D. @pytest.fixture(scope='session')
def browser():
driver = webdriver.Chrome()
driver.quit()
yield driver

Solution

1. Step 1: Choose correct fixture scope for session-wide browser

   Using scope='session' makes the fixture run once per test session.

2. Step 2: Verify setup and teardown order with yield

   Driver is created before yield (browser opens), and driver.quit() runs after all tests finish.

3. Final Answer:

   @pytest.fixture(scope='session')\ndef browser():\n driver = webdriver.Chrome()\n yield driver\n driver.quit() -> Option C

4. Quick Check:

   scope='session' + yield = one browser per session [OK]

Hint: Use scope='session' and yield for one browser per session [OK]

Common Mistakes:

• Using scope='function' for session-wide browser
• Calling driver.quit() before yield
• Yielding after driver.quit()