Exercises

Using the techniques you’ve just learned, create a new matcher named toHaveClass that replaces the following expectation:

expect(secondButton().className).toContain("toggled");

With your new matcher in place, it should read as follows:

expect(secondButton()).toHaveClass("toggled"); 

There is also the negated form of this matcher:

expect(secondButton().className).not.toContain("toggled");

Your matcher should work for this form and display an appropriate failure message.