public void Assign_should_override_a_field_instance_within_a_schema_when_invoked()
{
// Arrange
var sut = new Schema<Message>();
// Act
/// case 1: The property is one level down the member tree.
sut.Assign(x => x.Text, DataType.FullName);
var newTextType = sut[0].Type;
/// case 2: The property is two levels down the member tree.
sut.Assign(x => x.Writer.Name, DataType.FullName);
var newNameType = sut[2].Type;
/// case 3: The property is a list of objects.
sut.Assign(x => x.Tags, DataType.AppName);
var newTagType = sut[5].Type;
/// case 4: The property is a list of objects.
sut.Assign(x => x.Writer.Reviews.Item().Rating, DataType.RowNumber);
var newRatingType = sut[4].Type;
// Assert
newTextType.ShouldBe(DataType.FullName);
newNameType.ShouldBe(DataType.FullName);
newTagType.ShouldBe(DataType.AppName);
newRatingType.ShouldBe(DataType.RowNumber);
}