public void shouldGetNutrients()
{
var expectedNutrients = new[] {new Nutrient(), new Nutrient()};
var nutrientRepositoryMock = new Mock<INutrientRepository>();
nutrientRepositoryMock.Setup(x => x.GetAll()).Returns(expectedNutrients);
IEnumerable<Nutrient> returnedNutrients = new NutrientBusinessLogic(nutrientRepositoryMock.Object).GetNutrients();
Assert.That(returnedNutrients,Is.SameAs(expectedNutrients));
}