4.5Encapsulation: Hiding Implementation Details

Page objects should hide implementation details from tests. Tests should never contain locators, waits, or driver commands.

# BAD: locators and waits in the test
def test_add_to_cart(driver):
    driver.find_element(By.CSS_SELECTOR, ".product-card button.add").click()
    WebDriverWait(driver, 10).until(
        EC.text_to_be_present_in_element(
            (By.CSS_SELECTOR, ".cart-count"), "1"
        )
    )

# GOOD: all details inside the page object
def test_add_to_cart(driver):
    product_page = ProductPage(driver)
    product_page.add_first_item_to_cart()
    assert product_page.get_cart_count() == 1