Jasmine JavaScript Testing Framework Jasmine JavaScript Knowledge 4

Question 1

Which built-in Jasmine matcher checks that a value is strictly equal using `===`?

Accepted Answer

toBe()

Answer

toBe() uses strict equality (===), making it ideal for primitives and object reference checks.

Question 2

What is the difference between `toEqual()` and `toBe()` in Jasmine?

Accepted Answer

toEqual() does deep equality; toBe() checks reference/strict equality

Answer

toEqual() recursively compares object properties, while toBe() checks that both sides are the same object in memory.

Question 3

Which matcher would you use to verify a string contains a specific substring?

Accepted Answer

toContain()

Answer

toContain() checks whether a string includes the given substring, or an array includes a given element.

Question 4

How do you negate any Jasmine matcher?

Accepted Answer

expect(value).not.matcher()

Answer

Chaining .not before any matcher inverts its assertion, e.g., expect(x).not.toBe(null).

Question 5

Which matcher verifies that a function throws an error when invoked?

Accepted Answer

toThrow()

Answer

toThrow() (or the more specific toThrowError()) asserts that the wrapped function throws when called.

Jasmine JavaScript Testing Framework Practice Test