97 lines
1.9 KiB
Rust
97 lines
1.9 KiB
Rust
//@ run-pass
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#![allow(dead_code)]
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#![allow(unused_imports)]
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#![allow(deprecated)]
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#![allow(non_camel_case_types)]
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#![allow(non_snake_case)]
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#![allow(overflowing_literals)]
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use std::hash::{Hash, SipHasher, Hasher};
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use std::mem::size_of;
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#[derive(Hash)]
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struct Person {
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id: usize,
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name: String,
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phone: usize,
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}
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// test for hygiene name collisions
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#[derive(Hash)] struct __H__H;
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#[derive(Hash)] enum Collision<__H> { __H { __H__H: __H } }
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#[derive(Hash)]
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enum E { A=1, B }
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fn hash<T: Hash>(t: &T) -> u64 {
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let mut s = SipHasher::new();
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t.hash(&mut s);
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s.finish()
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}
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struct FakeHasher<'a>(&'a mut Vec<u8>);
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impl<'a> Hasher for FakeHasher<'a> {
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fn finish(&self) -> u64 {
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unimplemented!()
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}
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fn write(&mut self, bytes: &[u8]) {
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self.0.extend(bytes);
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}
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}
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fn fake_hash<A: Hash>(v: &mut Vec<u8>, a: A) {
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a.hash(&mut FakeHasher(v));
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}
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struct OnlyOneByteHasher;
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impl Hasher for OnlyOneByteHasher {
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fn finish(&self) -> u64 {
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unreachable!()
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}
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fn write(&mut self, bytes: &[u8]) {
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assert_eq!(bytes.len(), 1);
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}
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}
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fn main() {
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let person1 = Person {
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id: 5,
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name: "Janet".to_string(),
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phone: 555_666_7777
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};
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let person2 = Person {
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id: 5,
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name: "Bob".to_string(),
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phone: 555_666_7777
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};
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assert_eq!(hash(&person1), hash(&person1));
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assert!(hash(&person1) != hash(&person2));
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// test #21714
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let mut va = vec![];
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let mut vb = vec![];
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fake_hash(&mut va, E::A);
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fake_hash(&mut vb, E::B);
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assert!(va != vb);
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// issue #39137: single variant enum hash should not hash discriminant
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#[derive(Hash)]
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enum SingleVariantEnum {
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A(u8),
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}
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let mut v = vec![];
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fake_hash(&mut v, SingleVariantEnum::A(17));
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assert_eq!(vec![17], v);
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// issue #39137
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#[repr(u8)]
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#[derive(Hash)]
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enum E {
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A,
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B,
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}
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E::A.hash(&mut OnlyOneByteHasher);
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}
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