public void Area_RectangleObject_ReturnsArea()
{
// Arrange
var rectangle = new Faker <Rectangle>()
.CustomInstantiator(f =>
new Rectangle(
f.Random.Int(1, 10),
f.Random.Int(1, 10)))
.Generate();
var expectedResult = rectangle.Width * rectangle.Height;
// Act
var result = rectangle.Area();
// Assert
result.Should().Be(expectedResult);
}