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