src/librustc_data_structures/snapshot_map/tests.rs

   1 use super::SnapshotMap;
   2
   3 #[test]
   4 fn basic() {
   5     let mut map = SnapshotMap::default();
   6     map.insert(22, "twenty-two");
   7     let snapshot = map.snapshot();
   8     map.insert(22, "thirty-three");
   9     assert_eq!(map[&22], "thirty-three");
  10     map.insert(44, "forty-four");
  11     assert_eq!(map[&44], "forty-four");
  12     assert_eq!(map.get(&33), None);
  13     map.rollback_to(snapshot);
  14     assert_eq!(map[&22], "twenty-two");
  15     assert_eq!(map.get(&33), None);
  16     assert_eq!(map.get(&44), None);
  17 }
  18
  19 #[test]
  20 #[should_panic]
  21 fn out_of_order() {
  22     let mut map = SnapshotMap::default();
  23     map.insert(22, "twenty-two");
  24     let snapshot1 = map.snapshot();
  25     map.insert(33, "thirty-three");
  26     let snapshot2 = map.snapshot();
  27     map.insert(44, "forty-four");
  28     map.rollback_to(snapshot1); // bogus, but accepted
  29     map.rollback_to(snapshot2); // asserts
  30 }
  31
  32 #[test]
  33 fn nested_commit_then_rollback() {
  34     let mut map = SnapshotMap::default();
  35     map.insert(22, "twenty-two");
  36     let snapshot1 = map.snapshot();
  37     let snapshot2 = map.snapshot();
  38     map.insert(22, "thirty-three");
  39     map.commit(snapshot2);
  40     assert_eq!(map[&22], "thirty-three");
  41     map.rollback_to(snapshot1);
  42     assert_eq!(map[&22], "twenty-two");
  43 }