Verify login functionality with valid credentials

Preconditions (2)

Step 1: Enter 'user@example.com' in the email input field

Step 2: Enter 'Password123' in the password input field

Step 3: Click the login button

✅ Expected Result: User is redirected to the dashboard page with URL containing '/dashboard'

Automation Requirements - Selenium with Python

Assertions Needed:

Verify current URL contains '/dashboard' after login

Verify login button is clickable before clicking

Best Practices:

Use explicit waits to wait for elements to be clickable or visible

Use By.ID or By.NAME locators instead of XPath for better maintainability

Structure code with setup and teardown methods for browser management

Automated Solution

Testing Fundamentals

from selenium import webdriver
from selenium.webdriver.common.by import By
from selenium.webdriver.support.ui import WebDriverWait
from selenium.webdriver.support import expected_conditions as EC
import unittest

class TestLogin(unittest.TestCase):
    def setUp(self):
        self.driver = webdriver.Chrome()
        self.driver.get('https://example.com/login')
        self.wait = WebDriverWait(self.driver, 10)

    def test_valid_login(self):
        driver = self.driver
        wait = self.wait

        email_input = wait.until(EC.visibility_of_element_located((By.ID, 'email')))
        email_input.clear()
        email_input.send_keys('user@example.com')

        password_input = wait.until(EC.visibility_of_element_located((By.ID, 'password')))
        password_input.clear()
        password_input.send_keys('Password123')

        login_button = wait.until(EC.element_to_be_clickable((By.ID, 'login-button')))
        login_button.click()

        wait.until(EC.url_contains('/dashboard'))
        current_url = driver.current_url
        self.assertIn('/dashboard', current_url, 'User was not redirected to dashboard')

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

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

This test script uses Selenium with Python's unittest framework to automate the manual test case.

setUp() opens the browser and navigates to the login page.

test_valid_login() waits for the email and password fields to be visible, enters the given credentials, waits for the login button to be clickable, and clicks it.

Then it waits until the URL contains '/dashboard' to confirm successful login and asserts this condition.

tearDown() closes the browser after the test.

Explicit waits ensure the test waits for elements properly, avoiding flaky failures.

Common Mistakes - 3 Pitfalls

{'mistake': 'Using time.sleep() instead of explicit waits', 'why_bad': 'It causes tests to wait unnecessarily long or fail if the element loads slower or faster than expected.', 'correct_approach': "Use Selenium's explicit waits like WebDriverWait with expected_conditions."}

Using brittle XPath locators like absolute paths

Not clearing input fields before sending keys

Bonus Challenge

Now add data-driven testing with 3 different sets of valid credentials

Show Hint