15.4Migrating from Selenium to Playwright

Step 1: Concept Mapping

Selenium Concept	Playwright Equivalent
WebDriver / driver	Page / page
driver.get(url)	page.goto(url)
driver.find_element(By.ID, 'x')	page.locator('#x') or page.getByTestId('x')
element.click()	locator.click() (with auto-wait)
element.send_keys('text')	locator.fill('text')
WebDriverWait + expected_conditions	Auto-waiting (built-in)
driver.switch_to.frame()	page.frameLocator()
driver.quit()	Context/browser cleanup (automatic in test runner)
Selenium Grid	Built-in workers + sharding
Page Object with WebDriverWait	Page Object with Locators (no waits needed)

Step 2: Migration Strategy

Approach A: Gradual (Recommended)

1. New tests written in Playwright from day one
2. Run both suites in CI in parallel
3. Migrate existing tests by priority (critical paths first)
4. Decommission Selenium suite when coverage is equivalent

Approach B: Big Bang

1. Rewrite all tests in Playwright at once
2. Faster transition but higher risk
3. Only viable for small suites (< 100 tests)

Step 3: Common Conversion Patterns

# Selenium
from selenium.webdriver.support.ui import WebDriverWait
from selenium.webdriver.support import expected_conditions as EC

element = WebDriverWait(driver, 10).until(
    EC.element_to_be_clickable((By.CSS_SELECTOR, '[data-testid="submit"]'))
)
element.click()

# Playwright — no explicit wait needed
page.get_by_test_id("submit").click()

// Selenium (JS)
await driver.wait(until.elementLocated(By.id('result')), 10000);
const text = await driver.findElement(By.id('result')).getText();
assert.equal(text, 'Success');

// Playwright — web-first assertion retries automatically
await expect(page.locator('#result')).toHaveText('Success');