Local storage management in Cypress - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to clear all local storage data before each test.

Cypress

beforeEach(() => {
  cy.[1]();
});

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

AclearLocalStorage

BclearLocalStorage()

CclearLocalStorage.clear

DclearLocalStorage.clear()

Attempts:

3 left

💡 Hint

Common Mistakes

Forgetting the parentheses when calling the function.

Using incorrect method chaining.

In Cypress, cy.clearLocalStorage() is the correct command to clear all local storage data. It is a function and must be called with parentheses.

2fill in blank

medium

Complete the code to set a local storage item with key 'token' and value 'abc123'.

Cypress

cy.window().then((win) => {
  win.localStorage.[1]('token', 'abc123');
});

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

AsetItem

BgetItem

CremoveItem

Dclear

Attempts:

3 left

💡 Hint

Common Mistakes

Using getItem instead of setItem.

Trying to call clear which removes all items.

The setItem method stores a key-value pair in local storage. Here, it sets the key 'token' with the value 'abc123'.

3fill in blank

hard

Fix the error in the code to correctly assert that local storage has a key 'user' with value 'admin'.

Cypress

cy.window().then((win) => {
  expect(win.localStorage.[1]('user')).to.equal('admin');
});

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

AremoveItem

BsetItem

CgetItem

Dclear

Attempts:

3 left

💡 Hint

Common Mistakes

Using setItem which sets a value instead of getting it.

Using removeItem or clear which do not return values.

The getItem method retrieves the value for a given key from local storage. To check the value of 'user', we must use getItem('user').

4fill in blank

hard

Fill both blanks to create a test that sets a local storage item and then verifies it.

Cypress

cy.window().then((win) => {
  win.localStorage.[1]('session', 'xyz789');
  expect(win.localStorage.[2]('session')).to.equal('xyz789');
});

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

AsetItem

BgetItem

CremoveItem

Dclear

Attempts:

3 left

💡 Hint

Common Mistakes

Swapping setItem and getItem.

Using removeItem or clear incorrectly.

First, setItem stores the key 'session' with value 'xyz789'. Then, getItem retrieves it to verify the value.

5fill in blank

hard

Fill all three blanks to create a test that removes a local storage item and confirms it no longer exists.

Cypress

cy.window().then((win) => {
  win.localStorage.[1]('authToken', 'token123');
  win.localStorage.[2]('authToken');
  expect(win.localStorage.[3]('authToken')).to.be.null;
});

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

AsetItem

BgetItem

CremoveItem

Dclear

Attempts:

3 left

💡 Hint

Common Mistakes

Using clear instead of removeItem to delete a single key.

Checking the value before removing the item.

First, setItem adds the 'authToken'. Then, removeItem deletes it. Finally, getItem returns null confirming removal.

Practice

1. What is the primary purpose of local storage in a web browser when testing with Cypress?

easy

A. To run JavaScript code on the server

B. To store small amounts of data persistently for a website

C. To style the webpage dynamically

D. To manage network requests

Solution

1. Step 1: Understand local storage role

   Local storage is used by browsers to save small data like user preferences or tokens persistently.

2. Step 2: Connect with Cypress testing

   Cypress can access this storage to verify or manipulate data during tests.

3. Final Answer:

   To store small amounts of data persistently for a website -> Option B

4. Quick Check:

   Local storage = persistent small data [OK]

Hint: Local storage saves small data for the site, not server tasks [OK]

Common Mistakes:

• Confusing local storage with server-side storage
• Thinking local storage runs code
• Mixing local storage with styling or network

2. Which Cypress command is used to access the browser's window object to manage local storage?

easy

A. cy.document()

B. cy.getLocalStorage()

C. cy.localStorage()

D. cy.window()

Solution

1. Step 1: Recall Cypress commands for browser objects

   To access the browser's window object, Cypress provides cy.window().

2. Step 2: Understand local storage access

   Local storage is a property of the window object, so cy.window() is used to reach it.

3. Final Answer:

   cy.window() -> Option D

4. Quick Check:

   Access window with cy.window() [OK]

Hint: Use cy.window() to reach local storage via window object [OK]

Common Mistakes:

• Using non-existent commands like cy.getLocalStorage()
• Confusing cy.document() with window object
• Assuming cy.localStorage() exists

3. What will be the output of the following Cypress code snippet?

cy.window().then(win => {
  win.localStorage.setItem('user', 'Alice');
  const user = win.localStorage.getItem('user');
  cy.wrap(user).should('equal', 'Alice');
});

medium

A. Test will fail due to syntax error in setItem usage

B. Test will fail because localStorage is not accessible

C. Test will pass because 'user' is set and retrieved correctly

D. Test will pass but 'user' will be undefined

Solution

1. Step 1: Analyze localStorage set and get

   The code sets 'user' key to 'Alice' in localStorage, then retrieves it correctly.

2. Step 2: Check assertion correctness

   The assertion checks if retrieved value equals 'Alice', which is true, so test passes.

3. Final Answer:

   Test will pass because 'user' is set and retrieved correctly -> Option C

4. Quick Check:

   Set and get localStorage works, test passes [OK]

Hint: Setting then getting localStorage key returns correct value [OK]

Common Mistakes:

• Assuming localStorage is inaccessible in Cypress
• Thinking setItem syntax is wrong
• Expecting undefined instead of stored value

4. Identify the error in this Cypress code that tries to clear local storage:

cy.window().then(win => {
  win.localStorage.clear;
});

medium

A. Missing parentheses to call clear method

B. localStorage.clear requires a key argument

C. cy.window() cannot access localStorage

D. clear is not a function of localStorage

Solution

1. Step 1: Check localStorage clear usage

   localStorage.clear is a function and must be called with parentheses: clear()

2. Step 2: Identify missing parentheses error

   The code uses clear without parentheses, so it does not execute the function.

3. Final Answer:

   Missing parentheses to call clear method -> Option A

4. Quick Check:

   Call clear() with parentheses to clear storage [OK]

Hint: Always add () to call localStorage.clear() method [OK]

Common Mistakes:

• Forgetting parentheses when calling functions
• Thinking clear needs a key argument
• Assuming cy.window() can't access localStorage

5. You want to write a Cypress test that saves a token in local storage, reloads the page, and then verifies the token is still present. Which sequence of commands correctly achieves this?

hard

A. cy.window().then(win => win.localStorage.setItem('token', 'abc123')); cy.reload(); cy.window().then(win => expect(win.localStorage.getItem('token')).to.equal('abc123'));

B. cy.setLocalStorage('token', 'abc123'); cy.reload(); cy.getLocalStorage('token').should('equal', 'abc123');

C. cy.window().then(win => win.localStorage.setItem('token', 'abc123')); cy.reload(); cy.window().its('localStorage.token').should('equal', 'abc123');

D. cy.window().then(win => win.localStorage.clear()); cy.reload(); cy.window().its('localStorage.token').should('be.null');

Solution

1. Step 1: Save token in localStorage correctly

   Using cy.window().then(win => win.localStorage.setItem('token', 'abc123')) correctly sets the token.

2. Step 2: Reload and verify token presence

   After cy.reload(), accessing localStorage via cy.window().then and asserting with expect ensures token is still 'abc123'.

3. Step 3: Evaluate other options

   cy.window().then(win => win.localStorage.setItem('token', 'abc123')); cy.reload(); cy.window().its('localStorage.token').should('equal', 'abc123'); uses incorrect property access for localStorage token; cy.setLocalStorage('token', 'abc123'); cy.reload(); cy.getLocalStorage('token').should('equal', 'abc123'); uses non-existent commands; cy.window().then(win => win.localStorage.clear()); cy.reload(); cy.window().its('localStorage.token').should('be.null'); clears storage and checks for null, which is not the goal.

4. Final Answer:

   Use cy.window() to set, reload, then check with expect -> Option A

5. Quick Check:

   Set, reload, then assert with cy.window() and expect [OK]

Hint: Set token, reload, then check with cy.window() and expect [OK]

Common Mistakes:

• Using wrong localStorage property access
• Using non-existent Cypress commands
• Clearing storage instead of verifying token