Handling multiple pages in Selenium Python - Test Execution Trace

Test Overview

This test opens a website, clicks a link that opens a new page, switches to the new page, and verifies the new page's title.

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 TestMultiplePages(unittest.TestCase):
    def setUp(self):
        self.driver = webdriver.Chrome()
        self.driver.implicitly_wait(5)

    def test_switch_to_new_page(self):
        driver = self.driver
        driver.get('https://example.com')

        original_window = driver.current_window_handle

        # Click link that opens new page
        link = driver.find_element(By.LINK_TEXT, 'More information...')
        link.click()

        # Wait for new window
        WebDriverWait(driver, 10).until(EC.number_of_windows_to_be(2))

        # Switch to new window
        for window_handle in driver.window_handles:
            if window_handle != original_window:
                driver.switch_to.window(window_handle)
                break

        # Verify new page title
        self.assertEqual(driver.title, 'IANA — IANA-managed Reserved Domains')

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

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

Execution Trace - 8 Steps

Step	Action	System State	Assertion	Result
1	Test starts and Chrome browser opens	Browser window is open and ready	—	PASS
2	Navigates to 'https://example.com'	Example.com homepage is loaded	—	PASS
3	Stores current window handle as original_window	One browser tab open with example.com	—	PASS
4	Finds link with text 'More information...' and clicks it	New browser tab/window opens with new page	—	PASS
5	Waits until number of windows is 2	Two browser tabs/windows open	Number of windows equals 2	PASS
6	Switches to the new window that is not original_window	Driver controls new browser tab/window	—	PASS
7	Checks that new page title is 'IANA — IANA-managed Reserved Domains'	New page is fully loaded	Page title equals expected string	PASS
8	Test ends and browser closes	No browser windows open	—	PASS

Failure Scenario

Failing Condition: The link with text 'More information...' is not found or new window does not open

Execution Trace Quiz - 3 Questions

What does the test do after clicking the link that opens a new page?

A Refreshes the current page

B Closes the original window immediately

C Waits for the new window to open and switches to it

D Clicks the link again

Key Result

Always store the original window handle before opening a new page, then wait for the new window and switch to it before interacting or asserting on the new page.

Practice

1. What does driver.window_handles return in Selenium?

easy

A. The URL of the current page

B. The current active window handle only

C. The title of the current page

D. A list of all open browser window handles

Solution

1. Step 1: Understand what window handles represent

   Window handles are unique IDs for each open browser window or tab.

2. Step 2: Identify what driver.window_handles returns

   This property returns a list of all window handles currently opened by the driver.

3. Final Answer:

   A list of all open browser window handles -> Option D

4. Quick Check:

   window_handles = list of all windows [OK]

Hint: Remember: window_handles lists all open pages [OK]

Common Mistakes:

• Confusing window_handles with current window handle
• Expecting window_handles to return page titles or URLs
• Using window_handles as a single string instead of a list

2. Which is the correct syntax to switch to a new browser tab in Selenium Python?

easy

A. driver.switch_to_tab(driver.window_handles[1])

B. driver.switch_window(driver.window_handles[1])

C. driver.switch_to.window(driver.window_handles[1])

D. driver.change_window(driver.window_handles[1])

Solution

1. Step 1: Recall the correct method to switch windows

   The Selenium method to switch windows is driver.switch_to.window().

2. Step 2: Check the syntax for switching to the second tab

   Use the second handle in the list: driver.window_handles[1].

3. Final Answer:

   driver.switch_to.window(driver.window_handles[1]) -> Option C

4. Quick Check:

   Use switch_to.window with window_handles index [OK]

Hint: Use switch_to.window() with window_handles index [OK]

Common Mistakes:

• Using non-existent methods like switch_window or switch_to_tab
• Forgetting to use driver.switch_to
• Using wrong index for window_handles

3. What will the following code print if two tabs are open and the first tab's title is 'Home' and second tab's title is 'About'?

main_window = driver.current_window_handle
all_windows = driver.window_handles
for window in all_windows:
    driver.switch_to.window(window)
    print(driver.title)

medium

A. ["Home", "About"]

B. ["About", "Home"]

C. Only "Home"

D. Only "About"

Solution

1. Step 1: Understand the loop over all window handles

   The code loops over all open windows and switches to each one in order.

2. Step 2: Print the title of each window after switching

   It prints the title of each tab in the order of window_handles list, which is usually the order tabs opened.

3. Final Answer:

   ["Home", "About"] -> Option A

4. Quick Check:

   Loop prints titles of all tabs in order [OK]

Hint: Loop over window_handles prints all tab titles [OK]

Common Mistakes:

• Assuming only current tab title prints
• Mixing order of window handles
• Not switching before printing title

4. Identify the error in this code snippet that tries to switch back to the main window after opening a new tab:

main_window = driver.current_window_handle
# code to open new tab
driver.switch_to.window(driver.window_handles[1])
# do something
# switch back
driver.switch_to.window(main_window())

medium

A. Missing import for switch_to

B. main_window is called like a function with parentheses

C. driver.window_handles[1] is invalid index

D. No error, code is correct

Solution

1. Step 1: Check how main_window is used

   main_window is a string handle, but code calls main_window() as a function, which is incorrect.

2. Step 2: Identify correct usage to switch back

   Should use driver.switch_to.window(main_window) without parentheses.

3. Final Answer:

   main_window is called like a function with parentheses -> Option B

4. Quick Check:

   Window handle is a string, not a function [OK]

Hint: Window handles are strings, don't add () [OK]

Common Mistakes:

• Calling window handle variables as functions
• Using wrong index for window_handles
• Assuming switch_to needs import

5. You open multiple tabs during a test. How do you ensure you always return to the original tab after closing the new ones?

hard

A. Save the original window handle before opening new tabs and switch back using it

B. Use driver.close() on all tabs except the last one

C. Call driver.quit() to close all tabs and restart the browser

D. Switch to the last window handle in driver.window_handles list

Solution

1. Step 1: Save the original window handle before opening new tabs

   This allows you to remember which tab was the main one.

2. Step 2: After closing new tabs, switch back to the saved original handle

   Use driver.switch_to.window(original_handle) to return safely.

3. Final Answer:

   Save the original window handle before opening new tabs and switch back using it -> Option A

4. Quick Check:

   Save and reuse original handle to return [OK]

Hint: Always save main window handle before opening tabs [OK]

Common Mistakes:

• Assuming last window handle is original
• Closing tabs without switching back
• Using driver.quit() which ends session