must not be empty
must not contain quotes
must not contain slashes
must not contain question marks
Renamed sut
Degenerate example
Can enrol one person
Refactor: introduced Role
Can add multiple students to the same grade
Can add multiple students to different grades
Can get all students in a grade
Can get all students in non-existent grade
[GREEN] can sort the role
Refactor: eliminated middleman
Refactor: method renames
Formatting
Refactor: educated School