Parallel execution in CI in Selenium Python - Test Execution Trace

Test Overview

This test runs two simple Selenium tests in parallel using pytest-xdist in a Continuous Integration (CI) environment. It verifies that both tests open the browser, navigate to the page, and check the page title independently and simultaneously.

Test Code - pytest with pytest-xdist

Selenium Python

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

@pytest.fixture(scope="function")
def driver():
    driver = webdriver.Chrome()
    yield driver
    driver.quit()

@pytest.mark.parametrize("url,expected_title", [
    ("https://example.com", "Example Domain"),
    ("https://www.python.org", "Welcome to Python.org")
])
def test_parallel_execution(driver, url, expected_title):
    driver.get(url)
    assert driver.title == expected_title

Execution Trace - 6 Steps

Step	Action	System State	Assertion	Result
1	Test starts with pytest-xdist to run tests in parallel	CI environment ready to run tests concurrently	-	PASS
2	Two browser instances open simultaneously using webdriver.Chrome()	Two Chrome browsers launched independently	-	PASS
3	Each browser navigates to its assigned URL (example.com and python.org)	Browser 1 shows example.com, Browser 2 shows python.org	-	PASS
4	Each test checks the page title matches expected title	Browser 1 title is 'Example Domain', Browser 2 title is 'Welcome to Python.org'	Assert driver.title == expected_title for each test	PASS
5	Each browser instance closes after test completion	No browsers remain open	-	PASS
6	Pytest reports both tests passed in parallel	CI console shows both tests passed with no errors	Test report shows 2 passed tests	PASS

Failure Scenario

Failing Condition: One browser fails to open or navigate, or title assertion fails

Execution Trace Quiz - 3 Questions

What does pytest-xdist do in this test?

A Runs tests only on one browser instance

B Runs tests sequentially one after another

C Runs tests in parallel to speed up execution

D Skips tests that fail

Key Result

Running tests in parallel in CI saves time but requires each test to be independent with its own browser instance to avoid interference.