Vue JS Vue JS Testing and Debugging

Question 1

Which official Vue library is used to mount and test Vue components in isolation?

Accepted Answer

@vue/test-utils

Answer

vue-test-utils

Answer

vue-jest

Answer

vitest-vue

Question 2

What is the difference between mount() and shallowMount() in @vue/test-utils?

Accepted Answer

mount() fully renders child components; shallowMount() stubs child components

Answer

mount() is for Vue 3; shallowMount() is for Vue 2

Answer

shallowMount() runs faster because it uses SSR

Answer

mount() requires a real browser; shallowMount() runs in Node

Question 3

How do you trigger a button click event on a mounted component in @vue/test-utils?

Accepted Answer

wrapper.find('button').trigger('click')

Answer

wrapper.click()

Answer

wrapper.emit('click')

Answer

wrapper.get('button').fire('click')

Question 4

What does wrapper.vm expose in a @vue/test-utils mounted component?

Accepted Answer

The underlying Vue component instance

Answer

The raw HTML string of the component

Answer

The component's compiled render function

Answer

The virtual DOM node tree

Question 5

Which Vitest function is used to replace a module dependency with a test double in Vue unit tests?

Accepted Answer

vi.mock()

Answer

vitest.stub()

Answer

vitest.replace()

Answer

vi.spy()

Question 6

What is the purpose of nextTick() in Vue component tests?

Accepted Answer

Waits for Vue to finish processing pending DOM updates before assertions run

Answer

Delays test execution by one second

Answer

Triggers the next animation frame

Answer

Flushes all pending Axios requests