compiler/rustc_index/src/vec/tests.rs

   1 #![allow(dead_code)]
   2 newtype_index!(struct MyIdx { MAX = 0xFFFF_FFFA });
   3
   4 #[test]
   5 fn index_size_is_optimized() {
   6     use std::mem::size_of;
   7
   8     assert_eq!(size_of::<MyIdx>(), 4);
   9     // Uses 0xFFFF_FFFB
  10     assert_eq!(size_of::<Option<MyIdx>>(), 4);
  11     // Uses 0xFFFF_FFFC
  12     assert_eq!(size_of::<Option<Option<MyIdx>>>(), 4);
  13     // Uses 0xFFFF_FFFD
  14     assert_eq!(size_of::<Option<Option<Option<MyIdx>>>>(), 4);
  15     // Uses 0xFFFF_FFFE
  16     assert_eq!(size_of::<Option<Option<Option<Option<MyIdx>>>>>(), 4);
  17     // Uses 0xFFFF_FFFF
  18     assert_eq!(size_of::<Option<Option<Option<Option<Option<MyIdx>>>>>>(), 4);
  19     // Uses a tag
  20     assert_eq!(size_of::<Option<Option<Option<Option<Option<Option<MyIdx>>>>>>>(), 8);
  21 }
  22
  23 #[test]
  24 fn range_iterator_iterates_forwards() {
  25     let range = MyIdx::from_u32(1)..MyIdx::from_u32(4);
  26     assert_eq!(
  27         range.collect::<Vec<_>>(),
  28         [MyIdx::from_u32(1), MyIdx::from_u32(2), MyIdx::from_u32(3)]
  29     );
  30 }
  31
  32 #[test]
  33 fn range_iterator_iterates_backwards() {
  34     let range = MyIdx::from_u32(1)..MyIdx::from_u32(4);
  35     assert_eq!(
  36         range.rev().collect::<Vec<_>>(),
  37         [MyIdx::from_u32(3), MyIdx::from_u32(2), MyIdx::from_u32(1)]
  38     );
  39 }
  40
  41 #[test]
  42 fn range_count_is_correct() {
  43     let range = MyIdx::from_u32(1)..MyIdx::from_u32(4);
  44     assert_eq!(range.count(), 3);
  45 }
  46
  47 #[test]
  48 fn range_size_hint_is_correct() {
  49     let range = MyIdx::from_u32(1)..MyIdx::from_u32(4);
  50     assert_eq!(range.size_hint(), (3, Some(3)));
  51 }