expect(container.selectAll('rect').size()).toBe(2);// The 'provisional data message' adds a background rectangle that is always present in the legend, making the count one more than would be expected from the mock data
expect(container.selectAll('text').size()).toBe(5);// The 'provisional data message' is a text node that is always present in the legend, making the count one more than might be expected from the mock data