pytest with Selenium setup in Selenium Python - Test Execution Trace

Test Overview

This test opens a browser using Selenium with pytest, navigates to a website, checks the page title, and verifies it matches the expected title.

Test Code - pytest with Selenium

Selenium Python

import pytest
from selenium import webdriver
from selenium.webdriver.chrome.service import Service
from selenium.webdriver.common.by import By
from selenium.webdriver.chrome.options import Options

@pytest.fixture

def driver():
    options = Options()
    options.add_argument('--headless')
    service = Service()
    driver = webdriver.Chrome(service=service, options=options)
    yield driver
    driver.quit()


def test_page_title(driver):
    driver.get('https://example.com')
    title = driver.title
    assert title == 'Example Domain', f"Expected title to be 'Example Domain' but got '{title}'"

Execution Trace - 5 Steps

Step	Action	System State	Assertion	Result
1	Pytest starts and sets up the Chrome WebDriver with headless option	Chrome browser instance is created but not visible (headless mode)	—	PASS
2	Browser navigates to 'https://example.com'	Browser loads the Example Domain webpage	—	PASS
3	Test retrieves the page title using driver.title	Page title is 'Example Domain'	Check if page title equals 'Example Domain'	PASS
4	Assertion verifies the page title matches expected	Title matches expected string	assert title == 'Example Domain'	PASS
5	Browser quits and test ends	Browser instance closed	—	PASS

Failure Scenario

Failing Condition: Page title does not match 'Example Domain' or page fails to load

Execution Trace Quiz - 3 Questions

What does the test check after opening the browser and navigating to the page?

A The page title matches 'Example Domain'

B The page URL contains 'example.com'

C The page has a button with id 'submit'

D The page background color is white

Key Result

Using pytest fixtures to set up and tear down Selenium WebDriver ensures clean browser sessions for each test and avoids leftover browser processes.

Practice

1. What is the main purpose of using pytest fixtures in Selenium tests?

easy

A. To set up and tear down the browser before and after tests

B. To write assertions inside the test functions

C. To locate elements on the web page

D. To generate test reports automatically

Solution

1. Step 1: Understand pytest fixtures role

   Fixtures in pytest are used to prepare the test environment and clean up after tests, such as opening and closing browsers.

2. Step 2: Match fixture purpose with Selenium tests

   In Selenium tests, fixtures typically launch the browser before a test and close it after, ensuring clean test runs.

3. Final Answer:

   To set up and tear down the browser before and after tests -> Option A

4. Quick Check:

   Fixtures manage setup/cleanup = A [OK]

Hint: Fixtures handle setup and cleanup in tests [OK]

Common Mistakes:

• Confusing fixtures with assertions
• Thinking fixtures locate elements
• Assuming fixtures generate reports

2. Which of the following is the correct way to define a pytest fixture that opens a Chrome browser using Selenium?

easy

A. def browser():
driver = webdriver.Chrome()
yield driver
driver.quit()

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

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

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

Solution

1. Step 1: Identify correct pytest fixture decorator

   The correct decorator to define a fixture is @pytest.fixture.

2. Step 2: Check function structure for setup and teardown

   The function creates a driver, yields it for test use, then quits the driver after the test.

3. Final Answer:

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

4. Quick Check:

   Use @pytest.fixture for fixtures = A [OK]

Hint: Always use @pytest.fixture decorator for fixtures [OK]

Common Mistakes:

• Missing @pytest.fixture decorator
• Using wrong decorator like @pytest.test
• Forgetting to quit the driver

3. Given the following pytest test code, what will be the output when running the test?

import pytest
from selenium import webdriver

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


def test_google_title(browser):
    browser.get('https://www.google.com')
    assert 'Google' in browser.title

medium

A. Test passes if the browser opens Google and title contains 'Google'

B. Test fails because browser.title is empty

C. SyntaxError due to missing import

D. RuntimeError because driver.quit() is called too early

Solution

1. Step 1: Analyze fixture and test function

   The fixture opens Chrome, yields the driver, and quits after test. The test navigates to Google and asserts title contains 'Google'.

2. Step 2: Understand expected behavior

   Since Google page title contains 'Google', the assertion passes and test completes successfully.

3. Final Answer:

   Test passes if the browser opens Google and title contains 'Google' -> Option A

4. Quick Check:

   Title contains 'Google' means pass = B [OK]

Hint: Check page title contains expected text for pass [OK]

Common Mistakes:

• Assuming title is empty before page load
• Thinking driver.quit() runs before test
• Missing import statements

4. Identify the error in this pytest Selenium setup code:

import pytest
from selenium import webdriver

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


def test_example(browser):
    browser.get('https://example.com')
    assert 'Example' in browser.title

medium

A. Assertion syntax is incorrect

B. Missing @pytest.test decorator on test_example

C. driver.quit() is never called because it is after return

D. webdriver.Chrome() is not imported correctly

Solution

1. Step 1: Check fixture function flow

   The fixture returns driver before calling driver.quit(), so quit() never runs.

2. Step 2: Understand impact on test

   Without quitting, browser stays open, causing resource leaks and flaky tests.

3. Final Answer:

   driver.quit() is never called because it is after return -> Option C

4. Quick Check:

   Code after return is ignored = D [OK]

Hint: Put cleanup code after yield, not after return [OK]

Common Mistakes:

• Placing driver.quit() after return
• Confusing @pytest.test with @pytest.fixture
• Ignoring proper assertion syntax

5. You want to run a Selenium test with pytest that opens Firefox, navigates to a page, and checks a button is clickable. Which pytest fixture setup is best practice to ensure browser opens and closes properly?

hard

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

B. def browser():
driver = webdriver.Firefox()
return driver
driver.quit()

C. @pytest.fixture
def browser():
driver = webdriver.Firefox()
yield driver

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

Solution

1. Step 1: Review proper fixture structure for setup and teardown

   Best practice is to create driver, yield it for test use, then quit after test finishes.

2. Step 2: Evaluate each option

   @pytest.fixture def browser(): driver = webdriver.Firefox() yield driver driver.quit() correctly uses yield and calls quit after test. def browser(): driver = webdriver.Firefox() return driver driver.quit() quits after return (never runs). @pytest.fixture def browser(): driver = webdriver.Firefox() driver.quit() yield driver quits before yield (browser closed too early). @pytest.fixture def browser(): driver = webdriver.Firefox() yield driver never quits browser.

3. Final Answer:

   @pytest.fixture\ndef browser():\n driver = webdriver.Firefox()\n yield driver\n driver.quit() -> Option D

4. Quick Check:

   Yield before quit ensures proper cleanup = C [OK]

Hint: Yield driver, then quit after test for clean browser [OK]

Common Mistakes:

• Calling quit before yield
• Not quitting browser at all
• Using return instead of yield in fixture