Question 1

What is the role of the describe() function in Jest?

Accepted Answer

The describe() function groups multiple related tests together in a test suite. It improves readability by organizing tests by feature or component. Each describe() can contain multiple it() or test() to describe individual behaviors.

Question 2

What is the difference between it() and test() in Jest?

Accepted Answer

There is no functional difference between it() and test() in Jest. They are two aliases that do exactly the same thing. The choice between them is purely a matter of style and writing preference. Some prefer it() for a more natural BDD syntax, others prefer test() for clarity.

Question 3

Which Jest matcher should be used to verify that a value is strictly equal to another?

Accepted Answer

The toBe() matcher checks strict equality using the === operator in JavaScript. It compares references for objects, meaning two objects with the same content but different references won't be equal. To compare object content, use toEqual() instead.

Unit Testing

What is the role of the describe() function in Jest?

Câu trả lời

What is the difference between it() and test() in Jest?

Câu trả lời

Which Jest matcher should be used to verify that a value is strictly equal to another?

Câu trả lời

What is the difference between toEqual() and toStrictEqual()?

How to execute code before each test in a Jest suite?

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