Snapshot testing in iOS Swift - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is snapshot testing in iOS development?

Snapshot testing is a way to check if the visual appearance of a UI component stays the same over time by comparing its current look to a saved image.

beginner

Which framework is commonly used for snapshot testing in Swift?

The iOSSnapshotTestCase framework (also known as FBSnapshotTestCase) is commonly used for snapshot testing in Swift projects.

intermediate

Why is snapshot testing useful compared to manual UI checks?

Snapshot testing automates UI verification, catching visual bugs quickly and consistently without needing a person to look at the screen every time.

intermediate

What should you do if a snapshot test fails because the UI intentionally changed?

You should update the saved snapshot image to the new correct UI appearance to keep tests accurate.

advanced

Name one limitation of snapshot testing.

Snapshot testing can be fragile if small UI changes happen often, and it may not catch functional bugs that don't affect appearance.

What does a snapshot test compare?

A User input vs validation rules

B Code logic vs expected output

C Network response vs cached data

D Current UI image vs saved UI image

Snapshot tests compare the current UI image to a previously saved image to detect visual changes.

Which of these is a popular snapshot testing framework for Swift?

A XCTest

B iOSSnapshotTestCase

C Alamofire

D CoreData

iOSSnapshotTestCase is a popular framework specifically for snapshot testing in Swift.

If a UI change is intentional, what should you do with the snapshot test?

A Delete the test

B Ignore the failure

C Update the saved snapshot

D Revert the UI change

You should update the saved snapshot to reflect the new correct UI.

Snapshot testing is best described as:

A Testing UI appearance

B Testing app performance

C Testing backend APIs

D Testing user input validation

Snapshot testing focuses on verifying the UI appearance.

One limitation of snapshot testing is:

A It may fail often with small UI changes

B It requires manual UI checks

C It cannot detect visual bugs

D It tests only backend logic

Snapshot tests can be fragile and fail often if the UI changes frequently.

Explain how snapshot testing helps maintain UI quality in iOS apps.

Think about how comparing images can catch bugs without manual review.

Describe the steps to update a snapshot test after a UI change.

Consider what happens when the UI changes on purpose.