31 + Interview Questions in Jest in Frameworks Page 1 InterviewSolution

1.	The number can be compared using __________.
Answer» The NUMBER can be compared using __________. (1)toBeGreaterThanOrEqual (2)All the OPTIONS (3)toBeLessThan (4)toEqual (5)toBeGreaterThan Answer:-(2)All the options

Discussion

2.	For Code Coverage Support Jest requires some additional setup and libr
Answer» For CODE Coverage SUPPORT Jest REQUIRES some ADDITIONAL setup and libraries . (1)FALSE (2)True Answer:-(1)False

Discussion

3.	______________ resets all information stored in the mockFn.mock.calls and mockFn.mock.instances arrays.
Answer» ______________ resets all INFORMATION stored in the mockFn.mock.calls and mockFn.mock.instances arrays. (1)mockClear() (2)mockRestore() (3)mockReset() (4)All the options Answer:-(1)mockClear()

Discussion

4.	How to install Jest using yarn?
Answer» How to INSTALL Jest using yarn? (1)yarn install dev jest (2)yarn add --dev jest (3)yarn install --SAVE--dev jest (4)yarn add save--dev jest Answer:-(2)yarn add --dev jest

Discussion

5.	______________ matcher matches only undefined.
Answer» ______________ matcher MATCHES only UNDEFINED. (1)toBeDefined (2)toBeTruthy (3)toBeUndefined Answer:-(3)toBeUndefined

Discussion

6.	To test a particular function which throws an error when it's called, you can use toThrow.
Answer» To test a particular function which THROWS an error when it's called, you can USE toThrow. (1)False (2)True Answer:-(2)True

Discussion

7.	______________ resets all information stored in the mock, including any inital implementation given.
Answer» ______________ resets all INFORMATION STORED in the mock, including any inital implementation GIVEN. (1)mockReset() (2)All the options (3)mockClear() (4)mockRestore() ANSWER:-(1)mockReset()

Discussion

8.	Jest uses ________ and ________ matchers to test a value is with exact equality.
Answer» JEST uses ________ and ________ matchers to TEST a value is with EXACT equality. (1)toBeTruthy, toBeFalsy (2)ToBeEqual , toMatch (3)ToBe , toEqual (4)toBeUndefined, toBeDefined Answer:-(3)ToBe , toEqual

Discussion

9.	Jest records all calls that have been made during mock function and it is stored in ______________ array.
Answer» Jest RECORDS all CALLS that have been made during MOCK FUNCTION and it is stored in ______________ array. (1)mock.instances (2)mock.calls (3)mock.objectCalls (4)None of the options Answer:-(2)mock.calls

Discussion

10.	Snapshot tests are a useful tool whenever you want to make sure your UI does not change unexpectedly.
Answer» Snapshot tests are a useful tool whenever you want to make sure your UI does not CHANGE unexpectedly. (1)TRUE (2)False Answer:-(1)True

Discussion

11.	Jest will wait until the ______________ callback is called before finishing the test.
Answer» Jest will WAIT until the ______________ CALLBACK is called before finishing the test. (1)finish (2)do (3)DONE (4)NONE of the options Answer:-(3)done

Discussion

12.	mockRestore() removes the mock and restores the initial implementation
Answer» mockRestore() removes the MOCK and restores the initial IMPLEMENTATION. (1)FALSE (2)True Answer:-(2)True

Discussion

13.	The matcher toContain is used _________.
Answer» The matcher toContain is used _________. (1)to CHECK an OBJECT is PRESENT in a list (2)To check if a string contains a letter (3)none of the options (4)To check if an array contains a particular ITEM Answer:-(4)To check if an array contains a particular item

Discussion

14.	Snapshot Testing is not supported in Jest.
Answer» Snapshot Testing is not SUPPORTED in JEST. (1)FALSE (2)True Answer:-(1)False

Discussion

15.	_____ returns the value only once when mock function is called.
Answer» ______________ RETURNS the VALUE only once when mock function is CALLED. (1)NONE of the options (2)mockReturnOnce(value) (3)mockReturnValue(value) (4)mockReturnValueOnce(value) Answer:-(4)mockReturnValueOnce(value)

Discussion

16.	Code coverage tests that how much code is covered under tests.
Answer» CODE coverage TESTS that how MUCH code is covered under tests. (1)TRUE (2)False Answer:-(1)True

Discussion

17.	When you execute ______________ Code, it will move on to another task before it finishes.
Answer» When you execute ______________ Code, it will MOVE on to another TASK before it finishes. (1)SYNCHRONOUS (2)Asynchronous (3)both Answer:-(2)Asynchronous

Discussion

18.	Jest works well with other testing libraries like ______________.
Answer» Jest works well with other testing libraries LIKE ______________. (1)ENZYME (2)Chai (3)all the options (4)TestUtils Answer:-(3)all the options

Discussion

19.	Jest is maintained by ______________ .
Answer» Jest is maintained by ______________ . (1)Google (2)Facebook (3)Microsoft (4)apache Answer:-(2)Facebook

Discussion

20.	Jest is a JavaScript unit testing framework.
Answer» Jest is a JAVASCRIPT unit testing FRAMEWORK. (1)True (2)False Answer:-(1)True

Discussion

21.	Jest is used to test _____________.
Answer» Jest is used to TEST _____________. (1)Java (2)PYTHON (3)JAVASCRIPT (4)Ruby Answer:-(3)JavaScript

Discussion

22.	______________ recursively checks every field of an object or array.
Answer» ______________ recursively checks every field of an object or ARRAY. (1)TOMATCH (2)toBe (3)toBeEqual (4)toEqual Answer:-(4)toEqual

Discussion

23.	.mock is a property of mock function, the place where all information about how the function has been called is kept.
Answer» .MOCK is a property of mock function, the place where all information about how the function has been CALLED is kept. (1)FALSE (2)TRUE Answer:-(2)True

Discussion

24.	How to run your test in terminal?
Answer» How to run your test in TERMINAL? (1)npm test (2)all the OPTIONS (3)npm run test (4)npm t Answer:-(2)all the options

Discussion

25.	Jest supports _____for Isolating functionality into small testable
Answer» Jest SUPPORTS ______________ for Isolating FUNCTIONALITY into small, testable units under test. (1)MATCHERS (2)Mock Functions (3)Static Functions (4)None of the options Answer:-(2)Mock Functions

Discussion

26.	mockRestore() works only when mock was created with ______________.
Answer» mockRestore() works only when MOCK was CREATED with ______________. (1)jest.fn() (2)jest.spyFn() (3)jest.spyOn (4)jest.create() ANSWER:-(3)jest.spyOn

Discussion

27.	The Asynchronous code will move on to another task before it finishes.
Answer» The Asynchronous code will MOVE on to another TASK before it finishes. (1)FALSE (2)True Answer:-(2)True

Discussion

28.	What is the command to install Jest and the babel-jest?
Answer» What is the COMMAND to INSTALL Jest and the babel-jest? (1)$ npm install --save-dev jest babel-jest (2)$ npm install jest --save-dev babel-jest (3)$ npm install dev-save jest babel-jest (4)$ npm install -save-dev jest babel-jest Answer:-(1)$ npm install --save-dev jest babel-jest

Discussion

29.	The below test will pass.
Answer» The below test will pass. const value = 0.1 + 0.2; expect(value).TOBE(0.3); (1)True (2)FALSE Answer:-(2)False

Discussion

30.	You can check strings against regular expressions with ______________
Answer» You can check strings against regular expressions with ______________ . (1)TOMATCH (2)ToClose (3)TOBE (4)ToStrMatch Answer:-(1)toMatch

Discussion

31.	To create a mock function, we use *jest.fn()*.
Answer» To create a MOCK function, we USE *jest.fn()*. (1)True (2)False Answer:-(1)True

Discussion

Explore topic-wise InterviewSolutions in .

The number can be compared using __________.

For Code Coverage Support Jest requires some additional setup and libr

______________ resets all information stored in the mockFn.mock.calls and mockFn.mock.instances arrays.

How to install Jest using yarn?

______________ matcher matches only undefined.

To test a particular function which throws an error when it's called, you can use toThrow.

______________ resets all information stored in the mock, including any inital implementation given.

Jest uses and matchers to test a value is with exact equality.

Jest records all calls that have been made during mock function and it is stored in ______________ array.

Snapshot tests are a useful tool whenever you want to make sure your UI does not change unexpectedly.

Jest will wait until the ______________ callback is called before finishing the test.

mockRestore() removes the mock and restores the initial implementation

The matcher toContain is used _________.

Snapshot Testing is not supported in Jest.

_____ returns the value only once when mock function is called.

Code coverage tests that how much code is covered under tests.

When you execute ______________ Code, it will move on to another task before it finishes.

Jest works well with other testing libraries like ______________.

Jest is maintained by ______________ .

Jest is a JavaScript unit testing framework.

Jest is used to test _____________.

______________ recursively checks every field of an object or array.

.mock is a property of mock function, the place where all information about how the function has been called is kept.

How to run your test in terminal?

Jest supports _____for Isolating functionality into small testable

mockRestore() works only when mock was created with ______________.

The Asynchronous code will move on to another task before it finishes.

What is the command to install Jest and the babel-jest?

The below test will pass.

You can check strings against regular expressions with ______________

To create a mock function, we use jest.fn().

Explore topic-wise InterviewSolutions in .

The number can be compared using __________.

For Code Coverage Support Jest requires some additional setup and libr

______________ resets all information stored in the mockFn.mock.calls and mockFn.mock.instances arrays.

How to install Jest using yarn?

______________ matcher matches only undefined.

To test a particular function which throws an error when it's called, you can use toThrow.

______________ resets all information stored in the mock, including any inital implementation given.

Jest uses ________ and ________ matchers to test a value is with exact equality.

Jest records all calls that have been made during mock function and it is stored in ______________ array.

Snapshot tests are a useful tool whenever you want to make sure your UI does not change unexpectedly.

Jest will wait until the ______________ callback is called before finishing the test.

mockRestore() removes the mock and restores the initial implementation

The matcher toContain is used _________.

Snapshot Testing is not supported in Jest.

_____ returns the value only once when mock function is called.

Code coverage tests that how much code is covered under tests.

When you execute ______________ Code, it will move on to another task before it finishes.

Jest works well with other testing libraries like ______________.

Jest is maintained by ______________ .

Jest is a JavaScript unit testing framework.

Jest is used to test _____________.

______________ recursively checks every field of an object or array.

.mock is a property of mock function, the place where all information about how the function has been called is kept.

How to run your test in terminal?

Jest supports _____for Isolating functionality into small testable

mockRestore() works only when mock was created with ______________.

The Asynchronous code will move on to another task before it finishes.

What is the command to install Jest and the babel-jest?

The below test will pass.

You can check strings against regular expressions with ______________

To create a mock function, we use ***jest.fn()***.

Jest uses and matchers to test a value is with exact equality.

To create a mock function, we use jest.fn().