Screenshot on failure in Selenium Python - Practice Problems & Coding Challenges

Challenge - 5 Problems

❓ Predict Output

intermediate

What is the output when the test fails and screenshot is taken?

Consider the following Selenium Python test snippet that tries to find a non-existing element and takes a screenshot on failure. What will be the output or result of running this code?

Selenium Python

from selenium import webdriver
from selenium.common.exceptions import NoSuchElementException

try:
    driver = webdriver.Chrome()
    driver.get('https://example.com')
    driver.find_element('id', 'nonexistent')
except NoSuchElementException:
    driver.save_screenshot('failure.png')
    print('Screenshot saved on failure')
finally:
    driver.quit()

A Raises TimeoutException

B Screenshot saved on failure

C No output, test passes silently

D SyntaxError due to wrong method call

💡 Hint

Look at the exception caught and what happens inside the except block.

The code tries to find an element that does not exist, which raises NoSuchElementException. The except block catches it, saves a screenshot, and prints a message. So the output is the printed message.

❓ assertion

intermediate

Which assertion correctly verifies screenshot file creation after failure?

After a test failure and screenshot capture, which assertion correctly checks that the screenshot file 'failure.png' exists?

Selenium Python

import os

# Assume screenshot is saved as 'failure.png' in current directory

# Which assertion below is correct?

A assert os.path.isfile('failure.png')

B assert os.path.exists('failure.png') == False

C assert os.path.isdir('failure.png')

D assert os.path.isfile('failure.png') == False

💡 Hint

Check which function verifies a file exists.

os.path.isfile returns True if the path exists and is a file. This is the correct way to assert the screenshot file was created.

🔧 Debug

advanced

Why does this screenshot code fail to save the image?

This Selenium Python code is supposed to save a screenshot on failure but does not create any file. What is the likely cause?

Selenium Python

from selenium import webdriver
from selenium.common.exceptions import NoSuchElementException

try:
    driver = webdriver.Chrome()
    driver.get('https://example.com')
    driver.find_element('id', 'nonexistent')
except NoSuchElementException:
    driver.save_screenshot()
    print('Screenshot saved')
finally:
    driver.quit()

A save_screenshot requires a filename argument, missing here

B NoSuchElementException is not caught properly

C driver.quit() is called before save_screenshot

D driver.get() URL is invalid

💡 Hint

Check the method call for saving screenshots.

The save_screenshot method needs a filename string argument to save the image. Without it, a TypeError is raised and no file is created.

❓ framework

advanced

How to integrate screenshot on failure in pytest with Selenium?

Which pytest fixture code snippet correctly captures a screenshot on test failure using Selenium WebDriver?

A

import pytest

def pytest_runtest_setup(item):
    driver.save_screenshot('failure.png')

B

import pytest

@pytest.fixture(autouse=True)
def screenshot_on_failure(request, driver):
    yield
    if request.node.rep_call.failed:
        driver.save_screenshot('failure.png')

C

import pytest

@pytest.hookimpl(hookwrapper=True)
def pytest_runtest_makereport(item, call):
    outcome = yield
    rep = outcome.get_result()
    if rep.when == 'call' and rep.failed:
        driver = item.funcargs['driver']
        driver.save_screenshot('failure.png')

D

import pytest

@pytest.fixture
def driver():
    driver = webdriver.Chrome()
    yield driver
    driver.save_screenshot('failure.png')
    driver.quit()

💡 Hint

Look for pytest hook that runs after test call and can access test result.

Option C uses pytest's hook wrapper pytest_runtest_makereport to check if the test failed and then saves a screenshot using the driver fixture.

🧠 Conceptual

expert

Why is taking screenshots on failure important in automated UI testing?

Select the best reason why automated UI tests should capture screenshots when they fail.

A Screenshots replace the need for logs and error messages

B Screenshots reduce test execution time significantly

C Screenshots prevent tests from failing by fixing bugs automatically

D Screenshots provide visual evidence of the UI state at failure, aiding debugging

💡 Hint

Think about how visual context helps when tests fail.

Screenshots show exactly what the user would see when the test failed, making it easier to understand and fix issues.