public void Grade_returns_an_empty_list_if_there_are_no_students_in_that_grade()
{
var sut = new GradeSchool();
var expected = Array.Empty <string>();
Assert.Empty(sut.Grade(1));
}
public void Grade_returns_the_students_in_that_grade_in_alphabetical_order()
{
var sut = new GradeSchool();
sut.Add("Franklin", 5);
sut.Add("Bradley", 5);
sut.Add("Jeff", 1);
var expected = new[] { "Bradley", "Franklin" };
Assert.Equal(expected, sut.Grade(5));
}