React Native Quality Control & Assurance 2

Question 1

Which React Native testing library method is used to simulate a user pressing a button in a component test?

Accepted Answer

fireEvent.press(element)

Answer

fireEvent.press() from @testing-library/react-native simulates a press interaction on a component.

Question 2

What does the `act()` utility do in React Native tests?

Accepted Answer

It ensures all state updates and effects are processed before assertions

Answer

act() ensures that all pending state updates, effects, and re-renders are flushed before you make assertions.

Question 3

In Detox E2E tests, what command is used to find an element by its testID?

Accepted Answer

by.id('myId')

Answer

Detox uses by.id('testID') to locate elements via the testID prop set on React Native components.

Question 4

Which tool is commonly used for visual regression testing in React Native apps?

Accepted Answer

All of the above are valid approaches

Answer

Visual regression testing in React Native can use Storybook/Chromatic, Appium screenshots, or Jest snapshots depending on the scope.

Question 5

What is the purpose of `jest.useFakeTimers()` in React Native unit tests?

Accepted Answer

To control and advance time-dependent code like setTimeout and setInterval

Answer

jest.useFakeTimers() replaces native timer functions so tests can control time-based behavior without waiting.

React Native Practice Test