Yet another easy-to-forget-and-difficult-to-find answer. I was trying to remember how to set the selected option of a select element, and with Testing Library it’s as simple as this:

import { fireEvent, render } from "@testing-library/react";

it("sets the selected option", () => {
    const { findByTestId } = render(<SomeComponent />);

    const selectElement = await findByTestId('selectElementId');
    fireEvent.change(selectElement, { target: { value: valueOfDesiredOption }});
})

Happy Friday!