Initial vendor packages

Signed-off-by: Valentin Popov <valentin@popov.link>

1 files changed, 1445 insertions, 0 deletions

diff --git a/vendor/flume/tests/golang.rs b/vendor/flume/tests/golang.rs
new file mode 100644
index 0000000..ca00840
--- /dev/null
+++ b/vendor/flume/tests/golang.rs
@@ -0,0 +1,1445 @@
+// //! Tests copied from Go and manually rewritten in Rust.
+// //!
+// //! Source:
+// //!   - https://github.com/golang/go
+// //!
+// //! Copyright & License:
+// //!   - Copyright (c) 2009 The Go Authors
+// //!   - https://golang.org/AUTHORS
+// //!   - https://golang.org/LICENSE
+// //!   - https://golang.org/PATENTS
+
+// use std::any::Any;
+// use std::cell::Cell;
+// use std::collections::HashMap;
+// use std::sync::{Arc, Condvar, Mutex};
+// use std::thread;
+// use std::time::Duration;
+
+// use flume::{bounded, tick, Receiver, Select, Sender};
+
+// fn ms(ms: u64) -> Duration {
+//     Duration::from_millis(ms)
+// }
+
+// struct Chan<T> {
+//     inner: Arc<Mutex<ChanInner<T>>>,
+// }
+
+// struct ChanInner<T> {
+//     s: Option<Sender<T>>,
+//     r: Receiver<T>,
+// }
+
+// impl<T> Clone for Chan<T> {
+//     fn clone(&self) -> Chan<T> {
+//         Chan {
+//             inner: self.inner.clone(),
+//         }
+//     }
+// }
+
+// impl<T> Chan<T> {
+//     fn send(&self, msg: T) {
+//         let s = self
+//             .inner
+//             .lock()
+//             .unwrap()
+//             .s
+//             .as_ref()
+//             .expect("sending into closed channel")
+//             .clone();
+//         let _ = s.send(msg);
+//     }
+
+//     fn try_recv(&self) -> Option<T> {
+//         let r = self.inner.lock().unwrap().r.clone();
+//         r.try_recv().ok()
+//     }
+
+//     fn recv(&self) -> Option<T> {
+//         let r = self.inner.lock().unwrap().r.clone();
+//         r.recv().ok()
+//     }
+
+//     fn close(&self) {
+//         self.inner
+//             .lock()
+//             .unwrap()
+//             .s
+//             .take()
+//             .expect("channel already closed");
+//     }
+
+//     fn rx(&self) -> Receiver<T> {
+//         self.inner.lock().unwrap().r.clone()
+//     }
+
+//     fn tx(&self) -> Sender<T> {
+//         match self.inner.lock().unwrap().s.as_ref() {
+//             None => {
+//                 let (s, r) = bounded(0);
+//                 std::mem::forget(r);
+//                 s
+//             }
+//             Some(s) => s.clone(),
+//         }
+//     }
+// }
+
+// impl<T> Iterator for Chan<T> {
+//     type Item = T;
+
+//     fn next(&mut self) -> Option<Self::Item> {
+//         self.recv()
+//     }
+// }
+
+// impl<'a, T> IntoIterator for &'a Chan<T> {
+//     type Item = T;
+//     type IntoIter = Chan<T>;
+
+//     fn into_iter(self) -> Self::IntoIter {
+//         self.clone()
+//     }
+// }
+
+// fn make<T>(cap: usize) -> Chan<T> {
+//     let (s, r) = bounded(cap);
+//     Chan {
+//         inner: Arc::new(Mutex::new(ChanInner { s: Some(s), r })),
+//     }
+// }
+
+// #[derive(Clone)]
+// struct WaitGroup(Arc<WaitGroupInner>);
+
+// struct WaitGroupInner {
+//     cond: Condvar,
+//     count: Mutex<i32>,
+// }
+
+// impl WaitGroup {
+//     fn new() -> WaitGroup {
+//         WaitGroup(Arc::new(WaitGroupInner {
+//             cond: Condvar::new(),
+//             count: Mutex::new(0),
+//         }))
+//     }
+
+//     fn add(&self, delta: i32) {
+//         let mut count = self.0.count.lock().unwrap();
+//         *count += delta;
+//         assert!(*count >= 0);
+//         self.0.cond.notify_all();
+//     }
+
+//     fn done(&self) {
+//         self.add(-1);
+//     }
+
+//     fn wait(&self) {
+//         let mut count = self.0.count.lock().unwrap();
+//         while *count > 0 {
+//             count = self.0.cond.wait(count).unwrap();
+//         }
+//     }
+// }
+
+// struct Defer<F: FnOnce()> {
+//     f: Option<Box<F>>,
+// }
+
+// impl<F: FnOnce()> Drop for Defer<F> {
+//     fn drop(&mut self) {
+//         let f = self.f.take().unwrap();
+//         let mut f = Some(f);
+//         let mut f = move || f.take().unwrap()();
+//         f();
+//     }
+// }
+
+// macro_rules! defer {
+//     ($body:expr) => {
+//         let _defer = Defer {
+//             f: Some(Box::new(|| $body)),
+//         };
+//     };
+// }
+
+// macro_rules! go {
+//     (@parse ref $v:ident, $($tail:tt)*) => {{
+//         let ref $v = $v;
+//         go!(@parse $($tail)*)
+//     }};
+//     (@parse move $v:ident, $($tail:tt)*) => {{
+//         let $v = $v;
+//         go!(@parse $($tail)*)
+//     }};
+//     (@parse $v:ident, $($tail:tt)*) => {{
+//         let $v = $v.clone();
+//         go!(@parse $($tail)*)
+//     }};
+//     (@parse $body:expr) => {
+//         ::std::thread::spawn(move || {
+//             let res = ::std::panic::catch_unwind(::std::panic::AssertUnwindSafe(|| {
+//                 $body
+//             }));
+//             if res.is_err() {
+//                 eprintln!("goroutine panicked: {:?}", res);
+//                 ::std::process::abort();
+//             }
+//         })
+//     };
+//     (@parse $($tail:tt)*) => {
+//         compile_error!("invalid `go!` syntax")
+//     };
+//     ($($tail:tt)*) => {{
+//         go!(@parse $($tail)*)
+//     }};
+// }
+
+// // https://github.com/golang/go/blob/master/test/chan/doubleselect.go
+// mod doubleselect {
+//     use super::*;
+
+//     const ITERATIONS: i32 = 10_000;
+
+//     fn sender(n: i32, c1: Chan<i32>, c2: Chan<i32>, c3: Chan<i32>, c4: Chan<i32>) {
+//         defer! { c1.close() }
+//         defer! { c2.close() }
+//         defer! { c3.close() }
+//         defer! { c4.close() }
+
+//         for i in 0..n {
+//             select! {
+//                 send(c1.tx(), i) -> _ => {}
+//                 send(c2.tx(), i) -> _ => {}
+//                 send(c3.tx(), i) -> _ => {}
+//                 send(c4.tx(), i) -> _ => {}
+//             }
+//         }
+//     }
+
+//     fn mux(out: Chan<i32>, inp: Chan<i32>, done: Chan<bool>) {
+//         for v in inp {
+//             out.send(v);
+//         }
+//         done.send(true);
+//     }
+
+//     fn recver(inp: Chan<i32>) {
+//         let mut seen = HashMap::new();
+
+//         for v in &inp {
+//             if seen.contains_key(&v) {
+//                 panic!("got duplicate value for {}", v);
+//             }
+//             seen.insert(v, true);
+//         }
+//     }
+
+//     #[test]
+//     fn main() {
+//         let c1 = make::<i32>(0);
+//         let c2 = make::<i32>(0);
+//         let c3 = make::<i32>(0);
+//         let c4 = make::<i32>(0);
+//         let done = make::<bool>(0);
+//         let cmux = make::<i32>(0);
+
+//         go!(c1, c2, c3, c4, sender(ITERATIONS, c1, c2, c3, c4));
+//         go!(cmux, c1, done, mux(cmux, c1, done));
+//         go!(cmux, c2, done, mux(cmux, c2, done));
+//         go!(cmux, c3, done, mux(cmux, c3, done));
+//         go!(cmux, c4, done, mux(cmux, c4, done));
+//         go!(done, cmux, {
+//             done.recv();
+//             done.recv();
+//             done.recv();
+//             done.recv();
+//             cmux.close();
+//         });
+//         recver(cmux);
+//     }
+// }
+
+// // https://github.com/golang/go/blob/master/test/chan/fifo.go
+// mod fifo {
+//     use super::*;
+
+//     const N: i32 = 10;
+
+//     #[test]
+//     fn asynch_fifo() {
+//         let ch = make::<i32>(N as usize);
+//         for i in 0..N {
+//             ch.send(i);
+//         }
+//         for i in 0..N {
+//             if ch.recv() != Some(i) {
+//                 panic!("bad receive");
+//             }
+//         }
+//     }
+
+//     fn chain(ch: Chan<i32>, val: i32, inp: Chan<i32>, out: Chan<i32>) {
+//         inp.recv();
+//         if ch.recv() != Some(val) {
+//             panic!(val);
+//         }
+//         out.send(1);
+//     }
+
+//     #[test]
+//     fn synch_fifo() {
+//         let ch = make::<i32>(0);
+//         let mut inp = make::<i32>(0);
+//         let start = inp.clone();
+
+//         for i in 0..N {
+//             let out = make::<i32>(0);
+//             go!(ch, i, inp, out, chain(ch, i, inp, out));
+//             inp = out;
+//         }
+
+//         start.send(0);
+//         for i in 0..N {
+//             ch.send(i);
+//         }
+//         inp.recv();
+//     }
+// }
+
+// // https://github.com/golang/go/blob/master/test/chan/goroutines.go
+// mod goroutines {
+//     use super::*;
+
+//     fn f(left: Chan<i32>, right: Chan<i32>) {
+//         left.send(right.recv().unwrap());
+//     }
+
+//     #[test]
+//     fn main() {
+//         let n = 100i32;
+
+//         let leftmost = make::<i32>(0);
+//         let mut right = leftmost.clone();
+//         let mut left = leftmost.clone();
+
+//         for _ in 0..n {
+//             right = make::<i32>(0);
+//             go!(left, right, f(left, right));
+//             left = right.clone();
+//         }
+
+//         go!(right, right.send(1));
+//         leftmost.recv().unwrap();
+//     }
+// }
+
+// // https://github.com/golang/go/blob/master/test/chan/nonblock.go
+// mod nonblock {
+//     use super::*;
+
+//     fn i32receiver(c: Chan<i32>, strobe: Chan<bool>) {
+//         if c.recv().unwrap() != 123 {
+//             panic!("i32 value");
+//         }
+//         strobe.send(true);
+//     }
+
+//     fn i32sender(c: Chan<i32>, strobe: Chan<bool>) {
+//         c.send(234);
+//         strobe.send(true);
+//     }
+
+//     fn i64receiver(c: Chan<i64>, strobe: Chan<bool>) {
+//         if c.recv().unwrap() != 123456 {
+//             panic!("i64 value");
+//         }
+//         strobe.send(true);
+//     }
+
+//     fn i64sender(c: Chan<i64>, strobe: Chan<bool>) {
+//         c.send(234567);
+//         strobe.send(true);
+//     }
+
+//     fn breceiver(c: Chan<bool>, strobe: Chan<bool>) {
+//         if !c.recv().unwrap() {
+//             panic!("b value");
+//         }
+//         strobe.send(true);
+//     }
+
+//     fn bsender(c: Chan<bool>, strobe: Chan<bool>) {
+//         c.send(true);
+//         strobe.send(true);
+//     }
+
+//     fn sreceiver(c: Chan<String>, strobe: Chan<bool>) {
+//         if c.recv().unwrap() != "hello" {
+//             panic!("x value");
+//         }
+//         strobe.send(true);
+//     }
+
+//     fn ssender(c: Chan<String>, strobe: Chan<bool>) {
+//         c.send("hello again".to_string());
+//         strobe.send(true);
+//     }
+
+//     const MAX_TRIES: usize = 10000; // Up to 100ms per test.
+
+//     #[test]
+//     fn main() {
+//         let ticker = tick(Duration::new(0, 10_000)); // 10 us
+//         let sleep = || {
+//             ticker.recv().unwrap();
+//             ticker.recv().unwrap();
+//             thread::yield_now();
+//             thread::yield_now();
+//             thread::yield_now();
+//         };
+
+//         let sync = make::<bool>(0);
+
+//         for buffer in 0..2 {
+//             let c32 = make::<i32>(buffer);
+//             let c64 = make::<i64>(buffer);
+//             let cb = make::<bool>(buffer);
+//             let cs = make::<String>(buffer);
+
+//             select! {
+//                 recv(c32.rx()) -> _ => panic!("blocked i32sender"),
+//                 default => {}
+//             }
+
+//             select! {
+//                 recv(c64.rx()) -> _ => panic!("blocked i64sender"),
+//                 default => {}
+//             }
+
+//             select! {
+//                 recv(cb.rx()) -> _ => panic!("blocked bsender"),
+//                 default => {}
+//             }
+
+//             select! {
+//                 recv(cs.rx()) -> _ => panic!("blocked ssender"),
+//                 default => {}
+//             }
+
+//             go!(c32, sync, i32receiver(c32, sync));
+//             let mut try = 0;
+//             loop {
+//                 select! {
+//                     send(c32.tx(), 123) -> _ => break,
+//                     default => {
+//                         try += 1;
+//                         if try > MAX_TRIES {
+//                             println!("i32receiver buffer={}", buffer);
+//                             panic!("fail")
+//                         }
+//                         sleep();
+//                     }
+//                 }
+//             }
+//             sync.recv();
+//             go!(c32, sync, i32sender(c32, sync));
+//             if buffer > 0 {
+//                 sync.recv();
+//             }
+//             let mut try = 0;
+//             loop {
+//                 select! {
+//                     recv(c32.rx()) -> v => {
+//                         if v != Ok(234) {
+//                             panic!("i32sender value");
+//                         }
+//                         break;
+//                     }
+//                     default => {
+//                         try += 1;
+//                         if try > MAX_TRIES {
+//                             println!("i32sender buffer={}", buffer);
+//                             panic!("fail");
+//                         }
+//                         sleep();
+//                     }
+//                 }
+//             }
+//             if buffer == 0 {
+//                 sync.recv();
+//             }
+
+//             go!(c64, sync, i64receiver(c64, sync));
+//             let mut try = 0;
+//             loop {
+//                 select! {
+//                     send(c64.tx(), 123456) -> _ => break,
+//                     default => {
+//                         try += 1;
+//                         if try > MAX_TRIES {
+//                             println!("i64receiver buffer={}", buffer);
+//                             panic!("fail")
+//                         }
+//                         sleep();
+//                     }
+//                 }
+//             }
+//             sync.recv();
+//             go!(c64, sync, i64sender(c64, sync));
+//             if buffer > 0 {
+//                 sync.recv();
+//             }
+//             let mut try = 0;
+//             loop {
+//                 select! {
+//                     recv(c64.rx()) -> v => {
+//                         if v != Ok(234567) {
+//                             panic!("i64sender value");
+//                         }
+//                         break;
+//                     }
+//                     default => {
+//                         try += 1;
+//                         if try > MAX_TRIES {
+//                             println!("i64sender buffer={}", buffer);
+//                             panic!("fail");
+//                         }
+//                         sleep();
+//                     }
+//                 }
+//             }
+//             if buffer == 0 {
+//                 sync.recv();
+//             }
+
+//             go!(cb, sync, breceiver(cb, sync));
+//             let mut try = 0;
+//             loop {
+//                 select! {
+//                     send(cb.tx(), true) -> _ => break,
+//                     default => {
+//                         try += 1;
+//                         if try > MAX_TRIES {
+//                             println!("breceiver buffer={}", buffer);
+//                             panic!("fail")
+//                         }
+//                         sleep();
+//                     }
+//                 }
+//             }
+//             sync.recv();
+//             go!(cb, sync, bsender(cb, sync));
+//             if buffer > 0 {
+//                 sync.recv();
+//             }
+//             let mut try = 0;
+//             loop {
+//                 select! {
+//                     recv(cb.rx()) -> v => {
+//                         if v != Ok(true) {
+//                             panic!("bsender value");
+//                         }
+//                         break;
+//                     }
+//                     default => {
+//                         try += 1;
+//                         if try > MAX_TRIES {
+//                             println!("bsender buffer={}", buffer);
+//                             panic!("fail");
+//                         }
+//                         sleep();
+//                     }
+//                 }
+//             }
+//             if buffer == 0 {
+//                 sync.recv();
+//             }
+
+//             go!(cs, sync, sreceiver(cs, sync));
+//             let mut try = 0;
+//             loop {
+//                 select! {
+//                     send(cs.tx(), "hello".to_string()) -> _ => break,
+//                     default => {
+//                         try += 1;
+//                         if try > MAX_TRIES {
+//                             println!("sreceiver buffer={}", buffer);
+//                             panic!("fail")
+//                         }
+//                         sleep();
+//                     }
+//                 }
+//             }
+//             sync.recv();
+//             go!(cs, sync, ssender(cs, sync));
+//             if buffer > 0 {
+//                 sync.recv();
+//             }
+//             let mut try = 0;
+//             loop {
+//                 select! {
+//                     recv(cs.rx()) -> v => {
+//                         if v != Ok("hello again".to_string()) {
+//                             panic!("ssender value");
+//                         }
+//                         break;
+//                     }
+//                     default => {
+//                         try += 1;
+//                         if try > MAX_TRIES {
+//                             println!("ssender buffer={}", buffer);
+//                             panic!("fail");
+//                         }
+//                         sleep();
+//                     }
+//                 }
+//             }
+//             if buffer == 0 {
+//                 sync.recv();
+//             }
+//         }
+//     }
+// }
+
+// // https://github.com/golang/go/blob/master/test/chan/select.go
+// mod select {
+//     use super::*;
+
+//     #[test]
+//     fn main() {
+//         let shift = Cell::new(0);
+//         let counter = Cell::new(0);
+
+//         let get_value = || {
+//             counter.set(counter.get() + 1);
+//             1 << shift.get()
+//         };
+
+//         let send = |mut a: Option<&Chan<u32>>, mut b: Option<&Chan<u32>>| {
+//             let mut i = 0;
+//             let never = make::<u32>(0);
+//             loop {
+//                 let nil1 = never.tx();
+//                 let nil2 = never.tx();
+//                 let v1 = get_value();
+//                 let v2 = get_value();
+//                 select! {
+//                     send(a.map(|c| c.tx()).unwrap_or(nil1), v1) -> _ => {
+//                         i += 1;
+//                         a = None;
+//                     }
+//                     send(b.map(|c| c.tx()).unwrap_or(nil2), v2) -> _ => {
+//                         i += 1;
+//                         b = None;
+//                     }
+//                     default => break,
+//                 }
+//                 shift.set(shift.get() + 1);
+//             }
+//             i
+//         };
+
+//         let a = make::<u32>(1);
+//         let b = make::<u32>(1);
+
+//         assert_eq!(send(Some(&a), Some(&b)), 2);
+
+//         let av = a.recv().unwrap();
+//         let bv = b.recv().unwrap();
+//         assert_eq!(av | bv, 3);
+
+//         assert_eq!(send(Some(&a), None), 1);
+//         assert_eq!(counter.get(), 10);
+//     }
+// }
+
+// // https://github.com/golang/go/blob/master/test/chan/select2.go
+// mod select2 {
+//     // TODO
+// }
+
+// // https://github.com/golang/go/blob/master/test/chan/select3.go
+// mod select3 {
+//     // TODO
+// }
+
+// // https://github.com/golang/go/blob/master/test/chan/select4.go
+// mod select4 {
+//     use super::*;
+
+//     #[test]
+//     fn main() {
+//         let c = make::<i32>(1);
+//         let c1 = make::<i32>(0);
+//         c.send(42);
+//         select! {
+//             recv(c1.rx()) -> _ => panic!("BUG"),
+//             recv(c.rx()) -> v => assert_eq!(v, Ok(42)),
+//         }
+//     }
+// }
+
+// // https://github.com/golang/go/blob/master/test/chan/select6.go
+// mod select6 {
+//     use super::*;
+
+//     #[test]
+//     fn main() {
+//         let c1 = make::<bool>(0);
+//         let c2 = make::<bool>(0);
+//         let c3 = make::<bool>(0);
+
+//         go!(c1, c1.recv());
+//         go!(c1, c2, c3, {
+//             select! {
+//                 recv(c1.rx()) -> _ => panic!("dummy"),
+//                 recv(c2.rx()) -> _ => c3.send(true),
+//             }
+//             c1.recv();
+//         });
+//         go!(c2, c2.send(true));
+
+//         c3.recv();
+//         c1.send(true);
+//         c1.send(true);
+//     }
+// }
+
+// // https://github.com/golang/go/blob/master/test/chan/select7.go
+// mod select7 {
+//     use super::*;
+
+//     fn recv1(c: Chan<i32>) {
+//         c.recv().unwrap();
+//     }
+
+//     fn recv2(c: Chan<i32>) {
+//         select! {
+//             recv(c.rx()) -> _ => ()
+//         }
+//     }
+
+//     fn recv3(c: Chan<i32>) {
+//         let c2 = make::<i32>(1);
+//         select! {
+//             recv(c.rx()) -> _ => (),
+//             recv(c2.rx()) -> _ => ()
+//         }
+//     }
+
+//     fn send1(recv: fn(Chan<i32>)) {
+//         let c = make::<i32>(1);
+//         go!(c, recv(c));
+//         thread::yield_now();
+//         c.send(1);
+//     }
+
+//     fn send2(recv: fn(Chan<i32>)) {
+//         let c = make::<i32>(1);
+//         go!(c, recv(c));
+//         thread::yield_now();
+//         select! {
+//             send(c.tx(), 1) -> _ => ()
+//         }
+//     }
+
+//     fn send3(recv: fn(Chan<i32>)) {
+//         let c = make::<i32>(1);
+//         go!(c, recv(c));
+//         thread::yield_now();
+//         let c2 = make::<i32>(1);
+//         select! {
+//             send(c.tx(), 1) -> _ => (),
+//             send(c2.tx(), 1) -> _ => ()
+//         }
+//     }
+
+//     #[test]
+//     fn main() {
+//         send1(recv1);
+//         send2(recv1);
+//         send3(recv1);
+//         send1(recv2);
+//         send2(recv2);
+//         send3(recv2);
+//         send1(recv3);
+//         send2(recv3);
+//         send3(recv3);
+//     }
+// }
+
+// // https://github.com/golang/go/blob/master/test/chan/sieve1.go
+// mod sieve1 {
+//     use super::*;
+
+//     fn generate(ch: Chan<i32>) {
+//         let mut i = 2;
+//         loop {
+//             ch.send(i);
+//             i += 1;
+//         }
+//     }
+
+//     fn filter(in_ch: Chan<i32>, out_ch: Chan<i32>, prime: i32) {
+//         for i in in_ch {
+//             if i % prime != 0 {
+//                 out_ch.send(i);
+//             }
+//         }
+//     }
+
+//     fn sieve(primes: Chan<i32>) {
+//         let mut ch = make::<i32>(1);
+//         go!(ch, generate(ch));
+//         loop {
+//             let prime = ch.recv().unwrap();
+//             primes.send(prime);
+
+//             let ch1 = make::<i32>(1);
+//             go!(ch, ch1, prime, filter(ch, ch1, prime));
+//             ch = ch1;
+//         }
+//     }
+
+//     #[test]
+//     fn main() {
+//         let primes = make::<i32>(1);
+//         go!(primes, sieve(primes));
+
+//         let a = [
+//             2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61, 67, 71, 73, 79, 83,
+//             89, 97,
+//         ];
+//         for item in a.iter() {
+//             let x = primes.recv().unwrap();
+//             if x != *item {
+//                 println!("{} != {}", x, item);
+//                 panic!("fail");
+//             }
+//         }
+//     }
+// }
+
+// // https://github.com/golang/go/blob/master/test/chan/zerosize.go
+// mod zerosize {
+//     use super::*;
+
+//     #[test]
+//     fn zero_size_struct() {
+//         struct ZeroSize;
+//         let _ = make::<ZeroSize>(0);
+//     }
+
+//     #[test]
+//     fn zero_size_array() {
+//         let _ = make::<[u8; 0]>(0);
+//     }
+// }
+
+// // https://github.com/golang/go/blob/master/src/runtime/chan_test.go
+// mod chan_test {
+//     use super::*;
+
+//     #[test]
+//     fn test_chan() {
+//         const N: i32 = 200;
+
+//         for cap in 0..N {
+//             {
+//                 // Ensure that receive from empty chan blocks.
+//                 let c = make::<i32>(cap as usize);
+
+//                 let recv1 = Arc::new(Mutex::new(false));
+//                 go!(c, recv1, {
+//                     c.recv();
+//                     *recv1.lock().unwrap() = true;
+//                 });
+
+//                 let recv2 = Arc::new(Mutex::new(false));
+//                 go!(c, recv2, {
+//                     c.recv();
+//                     *recv2.lock().unwrap() = true;
+//                 });
+
+//                 thread::sleep(ms(1));
+
+//                 if *recv1.lock().unwrap() || *recv2.lock().unwrap() {
+//                     panic!();
+//                 }
+
+//                 // Ensure that non-blocking receive does not block.
+//                 select! {
+//                     recv(c.rx()) -> _ => panic!(),
+//                     default => {}
+//                 }
+//                 select! {
+//                     recv(c.rx()) -> _ => panic!(),
+//                     default => {}
+//                 }
+
+//                 c.send(0);
+//                 c.send(0);
+//             }
+
+//             {
+//                 // Ensure that send to full chan blocks.
+//                 let c = make::<i32>(cap as usize);
+//                 for i in 0..cap {
+//                     c.send(i);
+//                 }
+
+//                 let sent = Arc::new(Mutex::new(0));
+//                 go!(sent, c, {
+//                     c.send(0);
+//                     *sent.lock().unwrap() = 1;
+//                 });
+
+//                 thread::sleep(ms(1));
+
+//                 if *sent.lock().unwrap() != 0 {
+//                     panic!();
+//                 }
+
+//                 // Ensure that non-blocking send does not block.
+//                 select! {
+//                     send(c.tx(), 0) -> _ => panic!(),
+//                     default => {}
+//                 }
+//                 c.recv();
+//             }
+
+//             {
+//                 // Ensure that we receive 0 from closed chan.
+//                 let c = make::<i32>(cap as usize);
+//                 for i in 0..cap {
+//                     c.send(i);
+//                 }
+//                 c.close();
+
+//                 for i in 0..cap {
+//                     let v = c.recv();
+//                     if v != Some(i) {
+//                         panic!();
+//                     }
+//                 }
+
+//                 if c.recv() != None {
+//                     panic!();
+//                 }
+//                 if c.try_recv() != None {
+//                     panic!();
+//                 }
+//             }
+
+//             {
+//                 // Ensure that close unblocks receive.
+//                 let c = make::<i32>(cap as usize);
+//                 let done = make::<bool>(0);
+
+//                 go!(c, done, {
+//                     let v = c.try_recv();
+//                     done.send(v.is_some());
+//                 });
+
+//                 thread::sleep(ms(1));
+//                 c.close();
+
+//                 if !done.recv().unwrap() {
+//                     // panic!();
+//                 }
+//             }
+
+//             {
+//                 // Send 100 integers,
+//                 // ensure that we receive them non-corrupted in FIFO order.
+//                 let c = make::<i32>(cap as usize);
+//                 go!(c, {
+//                     for i in 0..100 {
+//                         c.send(i);
+//                     }
+//                 });
+//                 for i in 0..100 {
+//                     if c.recv() != Some(i) {
+//                         panic!();
+//                     }
+//                 }
+
+//                 // Same, but using recv2.
+//                 go!(c, {
+//                     for i in 0..100 {
+//                         c.send(i);
+//                     }
+//                 });
+//                 for i in 0..100 {
+//                     if c.recv() != Some(i) {
+//                         panic!();
+//                     }
+//                 }
+//             }
+//         }
+//     }
+
+//     #[test]
+//     fn test_nonblock_recv_race() {
+//         const N: usize = 1000;
+
+//         for _ in 0..N {
+//             let c = make::<i32>(1);
+//             c.send(1);
+
+//             let t = go!(c, {
+//                 select! {
+//                     recv(c.rx()) -> _ => {}
+//                     default => panic!("chan is not ready"),
+//                 }
+//             });
+
+//             c.close();
+//             c.recv();
+//             t.join().unwrap();
+//         }
+//     }
+
+//     #[test]
+//     fn test_nonblock_select_race() {
+//         const N: usize = 1000;
+
+//         let done = make::<bool>(1);
+//         for _ in 0..N {
+//             let c1 = make::<i32>(1);
+//             let c2 = make::<i32>(1);
+//             c1.send(1);
+
+//             go!(c1, c2, done, {
+//                 select! {
+//                     recv(c1.rx()) -> _ => {}
+//                     recv(c2.rx()) -> _ => {}
+//                     default => {
+//                         done.send(false);
+//                         return;
+//                     }
+//                 }
+//                 done.send(true);
+//             });
+
+//             c2.send(1);
+//             select! {
+//                 recv(c1.rx()) -> _ => {}
+//                 default => {}
+//             }
+//             if !done.recv().unwrap() {
+//                 panic!("no chan is ready");
+//             }
+//         }
+//     }
+
+//     #[test]
+//     fn test_nonblock_select_race2() {
+//         const N: usize = 1000;
+
+//         let done = make::<bool>(1);
+//         for _ in 0..N {
+//             let c1 = make::<i32>(1);
+//             let c2 = make::<i32>(0);
+//             c1.send(1);
+
+//             go!(c1, c2, done, {
+//                 select! {
+//                     recv(c1.rx()) -> _ => {}
+//                     recv(c2.rx()) -> _ => {}
+//                     default => {
+//                         done.send(false);
+//                         return;
+//                     }
+//                 }
+//                 done.send(true);
+//             });
+
+//             c2.close();
+//             select! {
+//                 recv(c1.rx()) -> _ => {}
+//                 default => {}
+//             }
+//             if !done.recv().unwrap() {
+//                 panic!("no chan is ready");
+//             }
+//         }
+//     }
+
+//     #[test]
+//     fn test_self_select() {
+//         // Ensure that send/recv on the same chan in select
+//         // does not crash nor deadlock.
+
+//         for &cap in &[0, 10] {
+//             let wg = WaitGroup::new();
+//             wg.add(2);
+//             let c = make::<i32>(cap);
+
+//             for p in 0..2 {
+//                 let p = p;
+//                 go!(wg, p, c, {
+//                     defer! { wg.done() }
+//                     for i in 0..1000 {
+//                         if p == 0 || i % 2 == 0 {
+//                             select! {
+//                                 send(c.tx(), p) -> _ => {}
+//                                 recv(c.rx()) -> v => {
+//                                     if cap == 0 && v.ok() == Some(p) {
+//                                         panic!("self receive");
+//                                     }
+//                                 }
+//                             }
+//                         } else {
+//                             select! {
+//                                 recv(c.rx()) -> v => {
+//                                     if cap == 0 && v.ok() == Some(p) {
+//                                         panic!("self receive");
+//                                     }
+//                                 }
+//                                 send(c.tx(), p) -> _ => {}
+//                             }
+//                         }
+//                     }
+//                 });
+//             }
+//             wg.wait();
+//         }
+//     }
+
+//     #[test]
+//     fn test_select_stress() {
+//         let c = vec![
+//             make::<i32>(0),
+//             make::<i32>(0),
+//             make::<i32>(2),
+//             make::<i32>(3),
+//         ];
+
+//         const N: usize = 10000;
+
+//         // There are 4 goroutines that send N values on each of the chans,
+//         // + 4 goroutines that receive N values on each of the chans,
+//         // + 1 goroutine that sends N values on each of the chans in a single select,
+//         // + 1 goroutine that receives N values on each of the chans in a single select.
+//         // All these sends, receives and selects interact chaotically at runtime,
+//         // but we are careful that this whole construct does not deadlock.
+//         let wg = WaitGroup::new();
+//         wg.add(10);
+
+//         for k in 0..4 {
+//             go!(k, c, wg, {
+//                 for _ in 0..N {
+//                     c[k].send(0);
+//                 }
+//                 wg.done();
+//             });
+//             go!(k, c, wg, {
+//                 for _ in 0..N {
+//                     c[k].recv();
+//                 }
+//                 wg.done();
+//             });
+//         }
+
+//         go!(c, wg, {
+//             let mut n = [0; 4];
+//             let mut c1 = c.iter().map(|c| Some(c.rx().clone())).collect::<Vec<_>>();
+
+//             for _ in 0..4 * N {
+//                 let index = {
+//                     let mut sel = Select::new();
+//                     let mut opers = [!0; 4];
+//                     for &i in &[3, 2, 0, 1] {
+//                         if let Some(c) = &c1[i] {
+//                             opers[i] = sel.recv(c);
+//                         }
+//                     }
+
+//                     let oper = sel.select();
+//                     let mut index = !0;
+//                     for i in 0..4 {
+//                         if opers[i] == oper.index() {
+//                             index = i;
+//                             let _ = oper.recv(c1[i].as_ref().unwrap());
+//                             break;
+//                         }
+//                     }
+//                     index
+//                 };
+
+//                 n[index] += 1;
+//                 if n[index] == N {
+//                     c1[index] = None;
+//                 }
+//             }
+//             wg.done();
+//         });
+
+//         go!(c, wg, {
+//             let mut n = [0; 4];
+//             let mut c1 = c.iter().map(|c| Some(c.tx().clone())).collect::<Vec<_>>();
+
+//             for _ in 0..4 * N {
+//                 let index = {
+//                     let mut sel = Select::new();
+//                     let mut opers = [!0; 4];
+//                     for &i in &[0, 1, 2, 3] {
+//                         if let Some(c) = &c1[i] {
+//                             opers[i] = sel.send(c);
+//                         }
+//                     }
+
+//                     let oper = sel.select();
+//                     let mut index = !0;
+//                     for i in 0..4 {
+//                         if opers[i] == oper.index() {
+//                             index = i;
+//                             let _ = oper.send(c1[i].as_ref().unwrap(), 0);
+//                             break;
+//                         }
+//                     }
+//                     index
+//                 };
+
+//                 n[index] += 1;
+//                 if n[index] == N {
+//                     c1[index] = None;
+//                 }
+//             }
+//             wg.done();
+//         });
+
+//         wg.wait();
+//     }
+
+//     #[test]
+//     fn test_select_fairness() {
+//         const TRIALS: usize = 10000;
+
+//         let c1 = make::<u8>(TRIALS + 1);
+//         let c2 = make::<u8>(TRIALS + 1);
+
+//         for _ in 0..TRIALS + 1 {
+//             c1.send(1);
+//             c2.send(2);
+//         }
+
+//         let c3 = make::<u8>(0);
+//         let c4 = make::<u8>(0);
+//         let out = make::<u8>(0);
+//         let done = make::<u8>(0);
+//         let wg = WaitGroup::new();
+
+//         wg.add(1);
+//         go!(wg, c1, c2, c3, c4, out, done, {
+//             defer! { wg.done() };
+//             loop {
+//                 let b;
+//                 select! {
+//                     recv(c3.rx()) -> m => b = m.unwrap(),
+//                     recv(c4.rx()) -> m => b = m.unwrap(),
+//                     recv(c1.rx()) -> m => b = m.unwrap(),
+//                     recv(c2.rx()) -> m => b = m.unwrap(),
+//                 }
+//                 select! {
+//                     send(out.tx(), b) -> _ => {}
+//                     recv(done.rx()) -> _ => return,
+//                 }
+//             }
+//         });
+
+//         let (mut cnt1, mut cnt2) = (0, 0);
+//         for _ in 0..TRIALS {
+//             match out.recv() {
+//                 Some(1) => cnt1 += 1,
+//                 Some(2) => cnt2 += 1,
+//                 b => panic!("unexpected value {:?} on channel", b),
+//             }
+//         }
+
+//         // If the select in the goroutine is fair,
+//         // cnt1 and cnt2 should be about the same value.
+//         // With 10,000 trials, the expected margin of error at
+//         // a confidence level of five nines is 4.4172 / (2 * Sqrt(10000)).
+
+//         let r = cnt1 as f64 / TRIALS as f64;
+//         let e = (r - 0.5).abs();
+
+//         if e > 4.4172 / (2.0 * (TRIALS as f64).sqrt()) {
+//             panic!(
+//                 "unfair select: in {} trials, results were {}, {}",
+//                 TRIALS, cnt1, cnt2,
+//             );
+//         }
+
+//         done.close();
+//         wg.wait();
+//     }
+
+//     #[test]
+//     fn test_chan_send_interface() {
+//         struct Mt;
+
+//         let c = make::<Box<dyn Any>>(1);
+//         c.send(Box::new(Mt));
+
+//         select! {
+//             send(c.tx(), Box::new(Mt)) -> _ => {}
+//             default => {}
+//         }
+
+//         select! {
+//             send(c.tx(), Box::new(Mt)) -> _ => {}
+//             send(c.tx(), Box::new(Mt)) -> _ => {}
+//             default => {}
+//         }
+//     }
+
+//     #[test]
+//     fn test_pseudo_random_send() {
+//         const N: usize = 100;
+
+//         for cap in 0..N {
+//             let c = make::<i32>(cap);
+//             let l = Arc::new(Mutex::new(vec![0i32; N]));
+//             let done = make::<bool>(0);
+
+//             go!(c, done, l, {
+//                 let mut l = l.lock().unwrap();
+//                 for i in 0..N {
+//                     thread::yield_now();
+//                     l[i] = c.recv().unwrap();
+//                 }
+//                 done.send(true);
+//             });
+
+//             for _ in 0..N {
+//                 select! {
+//                     send(c.tx(), 1) -> _ => {}
+//                     send(c.tx(), 0) -> _ => {}
+//                 }
+//             }
+//             done.recv();
+
+//             let mut n0 = 0;
+//             let mut n1 = 0;
+//             for &i in l.lock().unwrap().iter() {
+//                 n0 += (i + 1) % 2;
+//                 n1 += i;
+//             }
+
+//             if n0 <= N as i32 / 10 || n1 <= N as i32 / 10 {
+//                 panic!(
+//                     "Want pseudorandom, got {} zeros and {} ones (chan cap {})",
+//                     n0, n1, cap,
+//                 );
+//             }
+//         }
+//     }
+
+//     #[test]
+//     fn test_multi_consumer() {
+//         const NWORK: usize = 23;
+//         const NITER: usize = 271828;
+
+//         let pn = [2, 3, 7, 11, 13, 17, 19, 23, 27, 31];
+
+//         let q = make::<i32>(NWORK * 3);
+//         let r = make::<i32>(NWORK * 3);
+
+//         let wg = WaitGroup::new();
+//         for i in 0..NWORK {
+//             wg.add(1);
+//             let w = i;
+//             go!(q, r, wg, pn, {
+//                 for v in &q {
+//                     if pn[w % pn.len()] == v {
+//                         thread::yield_now();
+//                     }
+//                     r.send(v);
+//                 }
+//                 wg.done();
+//             });
+//         }
+
+//         let expect = Arc::new(Mutex::new(0));
+//         go!(q, r, expect, wg, pn, {
+//             for i in 0..NITER {
+//                 let v = pn[i % pn.len()];
+//                 *expect.lock().unwrap() += v;
+//                 q.send(v);
+//             }
+//             q.close();
+//             wg.wait();
+//             r.close();
+//         });
+
+//         let mut n = 0;
+//         let mut s = 0;
+//         for v in &r {
+//             n += 1;
+//             s += v;
+//         }
+
+//         if n != NITER || s != *expect.lock().unwrap() {
+//             panic!();
+//         }
+//     }
+
+//     #[test]
+//     fn test_select_duplicate_channel() {
+//         // This test makes sure we can queue a G on
+//         // the same channel multiple times.
+//         let c = make::<i32>(0);
+//         let d = make::<i32>(0);
+//         let e = make::<i32>(0);
+
+//         go!(c, d, e, {
+//             select! {
+//                 recv(c.rx()) -> _ => {}
+//                 recv(d.rx()) -> _ => {}
+//                 recv(e.rx()) -> _ => {}
+//             }
+//             e.send(9);
+//         });
+//         thread::sleep(ms(1));
+
+//         go!(c, c.recv());
+//         thread::sleep(ms(1));
+
+//         d.send(7);
+//         e.recv();
+//         c.send(8);
+//     }
+// }
+
+// // https://github.com/golang/go/blob/master/test/closedchan.go
+// mod closedchan {
+//     // TODO
+// }
+
+// // https://github.com/golang/go/blob/master/src/runtime/chanbarrier_test.go
+// mod chanbarrier_test {
+//     // TODO
+// }
+
+// // https://github.com/golang/go/blob/master/src/runtime/race/testdata/chan_test.go
+// mod race_chan_test {
+//     // TODO
+// }
+
+// // https://github.com/golang/go/blob/master/test/ken/chan.go
+// mod chan {
+//     // TODO
+// }
+
+// // https://github.com/golang/go/blob/master/test/ken/chan1.go
+// mod chan1 {
+//     // TODO
+// }