First Selenium script in Selenium Python - Test Execution Trace

Test Overview

This test opens a browser, goes to example.com, checks the page title, and closes the browser. It verifies the page loaded correctly by checking the title text.

Test Code - unittest

Selenium Python

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

class TestExampleDotCom(unittest.TestCase):
    def setUp(self):
        options = Options()
        options.add_argument('--headless')  # Run browser in headless mode
        service = Service()
        self.driver = webdriver.Chrome(service=service, options=options)

    def test_title(self):
        self.driver.get('https://example.com')
        title = self.driver.title
        self.assertEqual(title, 'Example Domain')

    def tearDown(self):
        self.driver.quit()

if __name__ == '__main__':
    unittest.main()

Execution Trace - 7 Steps

Step	Action	System State	Assertion	Result
1	Test starts - unittest framework initializes test case	No browser open yet	—	PASS
2	Browser opens in headless mode using ChromeDriver	Chrome browser running without UI	—	PASS
3	Navigates to 'https://example.com'	Browser loads example.com homepage	—	PASS
4	Reads page title	Page title is 'Example Domain'	Check if title equals 'Example Domain'	PASS
5	Assertion checks title equality	Title matches expected text	assertEqual(title, 'Example Domain')	PASS
6	Browser closes	No browser running	—	PASS
7	Test ends successfully	Test framework reports success	—	PASS

Failure Scenario

Failing Condition: Page title does not match 'Example Domain' due to navigation failure or page change

Execution Trace Quiz - 3 Questions

What does the test check after opening the browser?

A The page contains a login form

B The browser window size

C The page title is 'Example Domain'

D The URL contains 'test'

Key Result

Always verify key page elements like the title to confirm the page loaded correctly before continuing tests.

Practice

1. What is the main purpose of a Selenium script in software testing?

easy

A. To automate browser actions for testing websites

B. To write manual test cases on paper

C. To design website layouts

D. To create databases for applications

Solution

1. Step 1: Understand Selenium's role

   Selenium is a tool used to control browsers automatically for testing purposes.

2. Step 2: Match purpose with options

   Only To automate browser actions for testing websites describes automating browser actions to test websites, which is Selenium's main use.

3. Final Answer:

   To automate browser actions for testing websites -> Option A

4. Quick Check:

   Selenium automates browsers = B [OK]

Hint: Selenium controls browsers automatically for testing [OK]

Common Mistakes:

• Confusing Selenium with manual testing
• Thinking Selenium designs websites
• Mixing Selenium with database creation

2. Which of the following is the correct way to open a Chrome browser using Selenium in Python?

easy

A. driver = webdriver.open('chrome')

B. driver = webdriver.Firefox()

C. driver = webdriver.Chrome()

D. driver = webdriver.start('chrome')

Solution

1. Step 1: Recall Selenium syntax for Chrome

   In Selenium Python, opening Chrome uses webdriver.Chrome() constructor.

2. Step 2: Check options for correct syntax

   Only driver = webdriver.Chrome() uses the correct constructor. Others are either for different browsers or invalid methods.

3. Final Answer:

   driver = webdriver.Chrome() -> Option C

4. Quick Check:

   Open Chrome with webdriver.Chrome() = C [OK]

Hint: Use webdriver.Chrome() to open Chrome browser [OK]

Common Mistakes:

• Using webdriver.Firefox() for Chrome
• Calling non-existent methods like open() or start()
• Missing parentheses after Chrome

3. What will be the output of this Selenium Python code snippet?

from selenium import webdriver
from selenium.webdriver.common.by import By

driver = webdriver.Chrome()
driver.get('https://example.com')
element = driver.find_element(By.TAG_NAME, 'h1')
print(element.text)
driver.quit()

medium

A. Prints nothing because element.text is empty

B. Throws an error because By.TAG_NAME is invalid

C. Prints the URL 'https://example.com'

D. Prints the text inside the first <h1> tag on example.com

Solution

1. Step 1: Understand code actions

   The code opens Chrome, navigates to example.com, finds the first <h1> element, prints its text, then closes the browser.

2. Step 2: Analyze expected output

   example.com has an <h1> with text 'Example Domain', so element.text prints that text.

3. Final Answer:

   Prints the text inside the first <h1> tag on example.com -> Option D

4. Quick Check:

   find_element(By.TAG_NAME, 'h1') gets <h1> text = D [OK]

Hint: find_element with By.TAG_NAME gets first matching tag text [OK]

Common Mistakes:

• Thinking By.TAG_NAME is invalid
• Expecting URL printed instead of element text
• Assuming element.text is empty without checking page

4. Identify the error in this Selenium Python script:

from selenium import webdriver

driver = webdriver.Chrome
driver.get('https://example.com')
driver.quit()

medium

A. Missing parentheses after webdriver.Chrome to create driver instance

B. Incorrect URL format in driver.get() method

C. driver.quit() is called before opening browser

D. Indentation error on driver.get() line is invalid in Python

Solution

1. Step 1: Check webdriver.Chrome usage

   webdriver.Chrome is a class; to create a driver object, parentheses are needed: webdriver.Chrome()

2. Step 2: Review other lines for errors

   URL format is correct, driver.quit() is after get().

3. Step 3: Determine main error

   Missing parentheses causes driver to be a class, not an instance, so driver.get() will fail.

4. Final Answer:

   Missing parentheses after webdriver.Chrome to create driver instance -> Option A

5. Quick Check:

   webdriver.Chrome() needs parentheses = A [OK]

Hint: Always add () after webdriver.Chrome to create driver [OK]

Common Mistakes:

• Forgetting parentheses after webdriver.Chrome
• Thinking URL format is wrong
• Confusing the order of driver.get() and driver.quit()

5. You want to write a Selenium script that opens Chrome, goes to 'https://example.com', checks if the page title is 'Example Domain', and then closes the browser. Which code snippet correctly does this with an assertion?

hard

A. from selenium import webdriver
driver = webdriver.Chrome()
driver.get('https://example.com')
assert driver.title = 'Example Domain'
driver.quit()

B. from selenium import webdriver
driver = webdriver.Chrome()
driver.get('https://example.com')
assert driver.title == 'Example Domain'
driver.quit()

C. from selenium import webdriver
driver = webdriver.Chrome()
driver.get('https://example.com')
assert driver.title != 'Example Domain'
driver.quit()

D. from selenium import webdriver
driver = webdriver.Chrome()
driver.get('https://example.com')
assert driver.getTitle() == 'Example Domain'
driver.quit()

Solution

1. Step 1: Check correct assertion syntax

   In Python, assert uses '==' to compare values, so 'assert driver.title == "Example Domain"' is correct.

2. Step 2: Verify method and property names

   driver.title is the correct property for page title; driver.getTitle() is incorrect in Python Selenium.

3. Step 3: Confirm logic correctness

   from selenium import webdriver driver = webdriver.Chrome() driver.get('https://example.com') assert driver.title == 'Example Domain' driver.quit() asserts title equals 'Example Domain', which matches the requirement.

4. Final Answer:

   Correct assertion with driver.title == 'Example Domain' -> Option B

5. Quick Check:

   Use assert driver.title == 'Example Domain' = A [OK]

Hint: Use assert with '==' and driver.title property [OK]

Common Mistakes:

• Using single '=' instead of '==' in assert
• Using driver.getTitle() instead of driver.title
• Asserting title not equal instead of equal