[grade-school] a student can't be in two different grades test

I think the test means that a name can only be accepted in one grade and prevent duplicates. so typescript school.add('Aimee', 2) school.add('Aimee', 1) should prevent the second add while accepting the first one (because it is not a duplicate) . However the test expects an empty array : expect(school.grade(2)).toEqual([])
I think it is not a real use case to delete the first entry when a duplicate is being added. what do you think ?

You are correct. This has been fixed in problem specifications uuid 6a03b61e-1211-4783-a3cc-fc7f773fba3f but the typescript tests have not been updated.