Why POM organizes test code in Selenium Python - Test Execution Impact

Test Overview

This test opens a login page, enters username and password using Page Object Model (POM), clicks login, and verifies successful login message. It shows how POM organizes test code by separating page actions from test logic.

Test Code - Selenium

Selenium Python

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 LoginPage:
    def __init__(self, driver):
        self.driver = driver
        self.username_input = (By.ID, "username")
        self.password_input = (By.ID, "password")
        self.login_button = (By.ID, "loginBtn")

    def enter_username(self, username):
        self.driver.find_element(*self.username_input).send_keys(username)

    def enter_password(self, password):
        self.driver.find_element(*self.password_input).send_keys(password)

    def click_login(self):
        self.driver.find_element(*self.login_button).click()

class TestLogin(unittest.TestCase):
    def setUp(self):
        self.driver = webdriver.Chrome()
        self.driver.get("https://example.com/login")
        self.login_page = LoginPage(self.driver)

    def test_valid_login(self):
        self.login_page.enter_username("user1")
        self.login_page.enter_password("pass123")
        self.login_page.click_login()
        WebDriverWait(self.driver, 10).until(
            EC.presence_of_element_located((By.ID, "welcomeMsg"))
        )
        welcome_text = self.driver.find_element(By.ID, "welcomeMsg").text
        self.assertEqual(welcome_text, "Welcome user1!")

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

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

Execution Trace - 7 Steps

Step	Action	System State	Assertion	Result
1	Test starts and Chrome browser opens	Browser window is open at https://example.com/login page	-	PASS
2	Test calls enter_username method to find username input and types 'user1'	Username input field contains text 'user1'	-	PASS
3	Test calls enter_password method to find password input and types 'pass123'	Password input field contains text 'pass123'	-	PASS
4	Test calls click_login method to find and click login button	Login button clicked, page starts loading next screen	-	PASS
5	Test waits up to 10 seconds for element with ID 'welcomeMsg' to appear	Welcome message element is present on page	Verify welcome message text equals 'Welcome user1!'	PASS
6	Test asserts that welcome message text is exactly 'Welcome user1!'	Welcome message text is 'Welcome user1!'	assertEqual passes	PASS
7	Test ends and browser closes	Browser window closed	-	PASS

Failure Scenario

Failing Condition: If the login button ID changes or welcome message does not appear

Execution Trace Quiz - 3 Questions

What does the Page Object Model (POM) help organize in this test?

A Automatically generates test data

B Runs tests faster by skipping waits

C Separates page element locators and actions from test logic

D Replaces the need for assertions

Key Result

Using POM keeps test code clean and easy to maintain by putting page details in one place, so tests focus on verifying behavior.