System tests with Capybara in Ruby on Rails - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to visit the home page in a system test.

Ruby on Rails

visit [1]

Drag options to blanks, or click blank then click option'

A"/index"

B"/"

C"/home"

D"/dashboard"

Attempts:

3 left

💡 Hint

Common Mistakes

Using a path that does not exist like "/home" or "/index".

Forgetting to put quotes around the path.

The visit method navigates to the given path. The root path is "/".

2fill in blank

medium

Complete the code to check if the page has the text 'Welcome'.

Ruby on Rails

expect(page).to have_content([1])

Drag options to blanks, or click blank then click option'

A'Welcome'

B'Hello'

C'Goodbye'

D'Home'

Attempts:

3 left

💡 Hint

Common Mistakes

Checking for the wrong text like 'Hello' or 'Goodbye'.

Forgetting to put quotes around the text.

The have_content matcher checks if the page shows the given text. We want to check for 'Welcome'.

3fill in blank

hard

Fix the error in the code to fill in a form field labeled 'Email'.

Ruby on Rails

fill_in [1], with: '[e-mail]'

Drag options to blanks, or click blank then click option'

A'Email'

B'email'

C:email

D:Email

Attempts:

3 left

💡 Hint

Common Mistakes

Using symbols instead of strings for labels.

Using wrong case like 'email' instead of 'Email'.

The fill_in method expects the exact label text as a string. The label is 'Email' with capital E.

4fill in blank

hard

Fill both blanks to click a button labeled 'Submit' and then check the page has 'Success'.

Ruby on Rails

click_button([1])
expect(page).to have_content([2])

Drag options to blanks, or click blank then click option'

A'Submit'

B'Success'

C'Failed'

D'Cancel'

Attempts:

3 left

💡 Hint

Common Mistakes

Clicking the wrong button label.

Checking for wrong text after clicking.

Use click_button('Submit') to press the button. Then check for 'Success' text on the page.

5fill in blank

hard

Fill all three blanks to fill in 'Name', select 'Male' from 'Gender', and submit the form.

Ruby on Rails

fill_in [1], with: 'John'
select [2], from: 'Gender'
click_button [3]

Drag options to blanks, or click blank then click option'

A'Name'

B'Male'

C'Submit'

D'Female'

Attempts:

3 left

💡 Hint

Common Mistakes

Using wrong labels or options.

Forgetting quotes around labels.

Fill the 'Name' field, select 'Male' from the 'Gender' dropdown, then click the 'Submit' button.

Practice

1. What is the main purpose of system tests with Capybara in a Rails application?

easy

A. To test individual Ruby methods for correctness

B. To measure server response time under load

C. To check database schema migrations

D. To simulate user actions in a real browser and check app behavior

Solution

1. Step 1: Understand system tests role

   System tests simulate how a real user interacts with the app through a browser.

2. Step 2: Compare with other test types

   Unlike unit tests or performance tests, system tests focus on full app behavior with UI.

3. Final Answer:

   To simulate user actions in a real browser and check app behavior -> Option D

4. Quick Check:

   System tests = simulate user in browser [OK]

Hint: System tests mimic real user clicks and typing [OK]

Common Mistakes:

• Confusing system tests with unit tests
• Thinking system tests check only backend code
• Assuming system tests measure performance

2. Which of the following is the correct way to visit the homepage in a Capybara system test?

easy

A. navigate_to root_url

B. go_to '/'

C. visit root_path

D. open_page '/'

Solution

1. Step 1: Recall Capybara visit syntax

   Capybara uses the method visit with a path or URL to open a page.

2. Step 2: Match correct method and argument

   root_path is the Rails helper for homepage path, so visit root_path is correct.

3. Final Answer:

   visit root_path -> Option C

4. Quick Check:

   Capybara visit + path helper = visit root_path [OK]

Hint: Use 'visit' with Rails path helpers to open pages [OK]

Common Mistakes:

• Using non-existent methods like go_to or open_page
• Confusing root_path with root_url in system tests
• Forgetting to use visit before path

3. Given this system test code snippet, what will be the output on the page?

visit root_path
fill_in 'Email', with: '[e-mail]'
fill_in 'Password', with: 'secret'
click_button 'Log in'
expect(page).to have_content('Welcome, [e-mail]')

medium

A. Test passes if 'Welcome, [e-mail]' appears after login

B. Test fails because 'fill_in' cannot find fields

C. Test raises error due to missing 'visit' method

D. Test passes without checking page content

Solution

1. Step 1: Analyze test steps

   The test visits the homepage, fills in login form fields, clicks login, then checks for welcome message.

2. Step 2: Understand Capybara behavior

   If the login works and page shows the welcome text, have_content will pass and test passes.

3. Final Answer:

   Test passes if 'Welcome, [e-mail]' appears after login -> Option A

4. Quick Check:

   fill_in + click_button + have_content = success check [OK]

Hint: Check page content after actions to confirm success [OK]

Common Mistakes:

• Assuming fill_in fails without checking form existence
• Forgetting to call visit before actions
• Ignoring the expect(page).to have_content assertion

4. You wrote this system test but it fails with "Capybara::ElementNotFound" error:

visit root_path
fill_in 'Username', with: 'testuser'
click_button 'Submit'

What is the most likely cause?

medium

A. Capybara does not support fill_in method

B. The form does not have a field labeled 'Username'

C. The button 'Submit' is missing from the page

D. You forgot to call visit before fill_in

Solution

1. Step 1: Understand Capybara::ElementNotFound meaning

   This error means Capybara could not find the form field or button with given label.

2. Step 2: Check test code and error cause

   Since visit is called, the likely cause is the field labeled 'Username' does not exist on the page.

3. Final Answer:

   The form does not have a field labeled 'Username' -> Option B

4. Quick Check:

   ElementNotFound = missing field or button [OK]

Hint: Check labels exactly match form fields and buttons [OK]

Common Mistakes:

• Assuming visit was not called when it was
• Thinking Capybara lacks fill_in support
• Ignoring exact label spelling and case

5. You want to write a system test that logs in a user, visits their profile page, and verifies their username is shown. Which sequence correctly uses Capybara commands?

hard

A. visit login_path; fill_in 'Email', with: user.email; fill_in 'Password', with: user.password; click_button 'Log in'; visit profile_path(user); expect(page).to have_content(user.username)

B. fill_in 'Email', with: user.email; click_button 'Log in'; visit profile_path(user); expect(page).to have_content(user.username)

C. visit profile_path(user); fill_in 'Email', with: user.email; click_button 'Log in'; expect(page).to have_content(user.username)

D. visit login_path; click_button 'Log in'; fill_in 'Email', with: user.email; fill_in 'Password', with: user.password; expect(page).to have_content(user.username)

Solution

1. Step 1: Identify correct login flow

   You must visit the login page first, then fill in email and password, then click login.

2. Step 2: Visit profile after login and check content

   After successful login, visit the profile page and check the username is displayed.

3. Final Answer:

   visit login_path; fill_in 'Email', with: user.email; fill_in 'Password', with: user.password; click_button 'Log in'; visit profile_path(user); expect(page).to have_content(user.username) -> Option A

4. Quick Check:

   Login then visit profile then check content [OK]

Hint: Always visit pages before interacting or checking content [OK]

Common Mistakes:

• Trying to fill_in before visiting login page
• Visiting profile before logging in
• Clicking buttons before filling required fields