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-rw-r--r--vendor/rayon/tests/sort-panic-safe.rs164
1 files changed, 164 insertions, 0 deletions
diff --git a/vendor/rayon/tests/sort-panic-safe.rs b/vendor/rayon/tests/sort-panic-safe.rs
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+++ b/vendor/rayon/tests/sort-panic-safe.rs
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+use rand::distributions::Uniform;
+use rand::{thread_rng, Rng};
+use rayon::prelude::*;
+use std::cell::Cell;
+use std::cmp::{self, Ordering};
+use std::panic;
+use std::sync::atomic::AtomicUsize;
+use std::sync::atomic::Ordering::Relaxed;
+use std::thread;
+
+const ZERO: AtomicUsize = AtomicUsize::new(0);
+const LEN: usize = 20_000;
+
+static VERSIONS: AtomicUsize = ZERO;
+
+static DROP_COUNTS: [AtomicUsize; LEN] = [ZERO; LEN];
+
+#[derive(Clone, Eq)]
+struct DropCounter {
+ x: u32,
+ id: usize,
+ version: Cell<usize>,
+}
+
+impl PartialEq for DropCounter {
+ fn eq(&self, other: &Self) -> bool {
+ self.partial_cmp(other) == Some(Ordering::Equal)
+ }
+}
+
+impl PartialOrd for DropCounter {
+ fn partial_cmp(&self, other: &Self) -> Option<Ordering> {
+ self.version.set(self.version.get() + 1);
+ other.version.set(other.version.get() + 1);
+ VERSIONS.fetch_add(2, Relaxed);
+ self.x.partial_cmp(&other.x)
+ }
+}
+
+impl Ord for DropCounter {
+ fn cmp(&self, other: &Self) -> Ordering {
+ self.partial_cmp(other).unwrap()
+ }
+}
+
+impl Drop for DropCounter {
+ fn drop(&mut self) {
+ DROP_COUNTS[self.id].fetch_add(1, Relaxed);
+ VERSIONS.fetch_sub(self.version.get(), Relaxed);
+ }
+}
+
+macro_rules! test {
+ ($input:ident, $func:ident) => {
+ let len = $input.len();
+
+ // Work out the total number of comparisons required to sort
+ // this array...
+ let count = AtomicUsize::new(0);
+ $input.to_owned().$func(|a, b| {
+ count.fetch_add(1, Relaxed);
+ a.cmp(b)
+ });
+
+ let mut panic_countdown = count.load(Relaxed);
+ let step = if len <= 100 {
+ 1
+ } else {
+ cmp::max(1, panic_countdown / 10)
+ };
+
+ // ... and then panic after each `step` comparisons.
+ loop {
+ // Refresh the counters.
+ VERSIONS.store(0, Relaxed);
+ for i in 0..len {
+ DROP_COUNTS[i].store(0, Relaxed);
+ }
+
+ let v = $input.to_owned();
+ let _ = thread::spawn(move || {
+ let mut v = v;
+ let panic_countdown = AtomicUsize::new(panic_countdown);
+ v.$func(|a, b| {
+ if panic_countdown.fetch_sub(1, Relaxed) == 1 {
+ SILENCE_PANIC.with(|s| s.set(true));
+ panic!();
+ }
+ a.cmp(b)
+ })
+ })
+ .join();
+
+ // Check that the number of things dropped is exactly
+ // what we expect (i.e. the contents of `v`).
+ for (i, c) in DROP_COUNTS.iter().enumerate().take(len) {
+ let count = c.load(Relaxed);
+ assert!(
+ count == 1,
+ "found drop count == {} for i == {}, len == {}",
+ count,
+ i,
+ len
+ );
+ }
+
+ // Check that the most recent versions of values were dropped.
+ assert_eq!(VERSIONS.load(Relaxed), 0);
+
+ if panic_countdown < step {
+ break;
+ }
+ panic_countdown -= step;
+ }
+ };
+}
+
+thread_local!(static SILENCE_PANIC: Cell<bool> = Cell::new(false));
+
+#[test]
+#[cfg_attr(any(target_os = "emscripten", target_family = "wasm"), ignore)]
+fn sort_panic_safe() {
+ let prev = panic::take_hook();
+ panic::set_hook(Box::new(move |info| {
+ if !SILENCE_PANIC.with(Cell::get) {
+ prev(info);
+ }
+ }));
+
+ for &len in &[1, 2, 3, 4, 5, 10, 20, 100, 500, 5_000, 20_000] {
+ let len_dist = Uniform::new(0, len);
+ for &modulus in &[5, 30, 1_000, 20_000] {
+ for &has_runs in &[false, true] {
+ let mut rng = thread_rng();
+ let mut input = (0..len)
+ .map(|id| DropCounter {
+ x: rng.gen_range(0..modulus),
+ id,
+ version: Cell::new(0),
+ })
+ .collect::<Vec<_>>();
+
+ if has_runs {
+ for c in &mut input {
+ c.x = c.id as u32;
+ }
+
+ for _ in 0..5 {
+ let a = rng.sample(&len_dist);
+ let b = rng.sample(&len_dist);
+ if a < b {
+ input[a..b].reverse();
+ } else {
+ input.swap(a, b);
+ }
+ }
+ }
+
+ test!(input, par_sort_by);
+ test!(input, par_sort_unstable_by);
+ }
+ }
+ }
+}