error: duplicate variant `Var` in enum `Enum`
  --> test/ui/duplicate_enum_variant.aldrin:3:5
   |
 3 |     Var @ 2;
   |     ^^^ duplicate defined here
   |
  ::: test/ui/duplicate_enum_variant.aldrin:2:5
   |
 2 |     Var @ 1;
   |     --- first defined here
   |
