3 use std::default::Default;
4 use std::hash::{BuildHasher, Hash, Hasher};
12 impl Default for MyHasher {
13 fn default() -> MyHasher {
18 impl Hasher for MyHasher {
19 fn write(&mut self, buf: &[u8]) {
21 self.hash += *byte as u64;
24 fn write_str(&mut self, s: &str) {
25 self.write(s.as_bytes());
28 fn finish(&self) -> u64 {
34 fn test_writer_hasher() {
35 fn hash<T: Hash>(t: &T) -> u64 {
36 let mut s = MyHasher { hash: 0 };
41 assert_eq!(hash(&()), 0);
43 assert_eq!(hash(&5_u8), 5);
44 assert_eq!(hash(&5_u16), 5);
45 assert_eq!(hash(&5_u32), 5);
46 assert_eq!(hash(&5_u64), 5);
47 assert_eq!(hash(&5_usize), 5);
49 assert_eq!(hash(&5_i8), 5);
50 assert_eq!(hash(&5_i16), 5);
51 assert_eq!(hash(&5_i32), 5);
52 assert_eq!(hash(&5_i64), 5);
53 assert_eq!(hash(&5_isize), 5);
55 assert_eq!(hash(&false), 0);
56 assert_eq!(hash(&true), 1);
58 assert_eq!(hash(&'a'), 97);
61 assert_eq!(hash(&s), 97 + 0xFF);
62 let s: Box<str> = String::from("a").into_boxed_str();
63 assert_eq!(hash(&s), 97 + 0xFF);
64 let s: Rc<&str> = Rc::new("a");
65 assert_eq!(hash(&s), 97 + 0xFF);
66 let cs: &[u8] = &[1, 2, 3];
67 assert_eq!(hash(&cs), 9);
68 let cs: Box<[u8]> = Box::new([1, 2, 3]);
69 assert_eq!(hash(&cs), 9);
70 let cs: Rc<[u8]> = Rc::new([1, 2, 3]);
71 assert_eq!(hash(&cs), 9);
73 let ptr = ptr::invalid::<i32>(5_usize);
74 assert_eq!(hash(&ptr), 5);
76 let ptr = ptr::invalid_mut::<i32>(5_usize);
77 assert_eq!(hash(&ptr), 5);
80 // Miri cannot hash pointers
84 let cs: &mut [u8] = &mut [1, 2, 3];
85 let ptr = cs.as_ptr();
86 let slice_ptr = cs as *const [u8];
87 assert_eq!(hash(&slice_ptr), hash(&ptr) + cs.len() as u64);
89 let slice_ptr = cs as *mut [u8];
90 assert_eq!(hash(&slice_ptr), hash(&ptr) + cs.len() as u64);
100 impl Hasher for CustomHasher {
101 fn finish(&self) -> u64 {
104 fn write(&mut self, _: &[u8]) {
107 fn write_u64(&mut self, data: u64) {
112 impl Default for CustomHasher {
113 fn default() -> CustomHasher {
114 CustomHasher { output: 0 }
118 impl Hash for Custom {
119 fn hash<H: Hasher>(&self, state: &mut H) {
120 state.write_u64(self.hash);
125 fn test_custom_state() {
126 fn hash<T: Hash>(t: &T) -> u64 {
127 let mut c = CustomHasher { output: 0 };
132 assert_eq!(hash(&Custom { hash: 5 }), 5);
135 // FIXME: Instantiated functions with i128 in the signature is not supported in Emscripten.
136 // See https://github.com/kripken/emscripten-fastcomp/issues/169
137 #[cfg(not(target_os = "emscripten"))]
139 fn test_indirect_hasher() {
140 let mut hasher = MyHasher { hash: 0 };
142 let mut indirect_hasher: &mut dyn Hasher = &mut hasher;
143 5u32.hash(&mut indirect_hasher);
145 assert_eq!(hasher.hash, 5);
149 fn test_build_hasher_object_safe() {
150 use std::collections::hash_map::{DefaultHasher, RandomState};
152 let _: &dyn BuildHasher<Hasher = DefaultHasher> = &RandomState::new();
155 // just tests by whether or not this compiles
156 fn _build_hasher_default_impl_all_auto_traits<T>() {
157 use std::panic::{RefUnwindSafe, UnwindSafe};
158 fn all_auto_traits<T: Send + Sync + Unpin + UnwindSafe + RefUnwindSafe>() {}
160 all_auto_traits::<std::hash::BuildHasherDefault<T>>();