rust/library/std/tests/common/mod.rs

58 lines
1.7 KiB
Rust

#![allow(unused)]
use std::path::{Path, PathBuf};
use std::{env, fs, thread};
use rand::RngCore;
/// Copied from `std::test_helpers::test_rng`, since these tests rely on the
/// seed not being the same for every RNG invocation too.
#[track_caller]
pub(crate) fn test_rng() -> rand_xorshift::XorShiftRng {
use core::hash::{BuildHasher, Hash, Hasher};
let mut hasher = std::hash::RandomState::new().build_hasher();
core::panic::Location::caller().hash(&mut hasher);
let hc64 = hasher.finish();
let seed_vec = hc64.to_le_bytes().into_iter().chain(0u8..8).collect::<Vec<u8>>();
let seed: [u8; 16] = seed_vec.as_slice().try_into().unwrap();
rand::SeedableRng::from_seed(seed)
}
// Copied from std::sys_common::io
pub(crate) struct TempDir(PathBuf);
impl TempDir {
pub(crate) fn join(&self, path: &str) -> PathBuf {
let TempDir(ref p) = *self;
p.join(path)
}
pub(crate) fn path(&self) -> &Path {
let TempDir(ref p) = *self;
p
}
}
impl Drop for TempDir {
fn drop(&mut self) {
// Gee, seeing how we're testing the fs module I sure hope that we
// at least implement this correctly!
let TempDir(ref p) = *self;
let result = fs::remove_dir_all(p);
// Avoid panicking while panicking as this causes the process to
// immediately abort, without displaying test results.
if !thread::panicking() {
result.unwrap();
}
}
}
#[track_caller] // for `test_rng`
pub(crate) fn tmpdir() -> TempDir {
let p = env::temp_dir();
let mut r = test_rng();
let ret = p.join(&format!("rust-{}", r.next_u32()));
fs::create_dir(&ret).unwrap();
TempDir(ret)
}