`toBeInstanceOf(Number)` does not work in jest

expect(value).not.toBeNaN();

Edit: I would go with @bszoms solution:

expect(typeof value).toBe('number')

The following works for all constructors:

expect(value).toEqual(expect.any(Number));

You can also do this: expect(typeof <value>).toBe('number')

Or you can use jest-extended, which adds a whole range of matchers including toBeNumber.

Both courtesy of the discussion here.

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