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#![allow(clippy::redundant_clone)]
#![warn(rust_2018_idioms)]
#![cfg(feature = "sync")]
#[cfg(all(target_family = "wasm", not(target_os = "wasi")))]
use wasm_bindgen_test::wasm_bindgen_test as test;
use tokio::sync::broadcast::{self, channel};
#[tokio::test]
async fn weak_sender() {
let (tx, mut rx) = channel(11);
let tx_weak = tokio::spawn(async move {
let tx_weak = tx.clone().downgrade();
for i in 0..10 {
if tx.send(i).is_err() {
return None;
}
}
let tx2 = tx_weak
.upgrade()
.expect("expected to be able to upgrade tx_weak");
let _ = tx2.send(20);
let tx_weak = tx2.downgrade();
Some(tx_weak)
})
.await
.unwrap();
for i in 0..12 {
let recvd = rx.recv().await;
match recvd {
Ok(msg) => {
if i == 10 {
assert_eq!(msg, 20);
}
}
Err(_) => {
assert_eq!(i, 11);
break;
}
}
}
let tx_weak = tx_weak.unwrap();
let upgraded = tx_weak.upgrade();
assert!(upgraded.is_none());
}
// Tests that a `WeakSender` fails to upgrade when no other `Sender` exists.
#[test]
fn downgrade_upgrade_sender_failure() {
let (tx, _rx) = broadcast::channel::<i32>(1);
let weak_tx = tx.downgrade();
drop(tx);
assert!(weak_tx.upgrade().is_none());
}
// Tests that a `WeakSender` cannot be upgraded after a `Sender` was dropped,
// which existed at the time of the `downgrade` call.
#[test]
fn downgrade_drop_upgrade() {
let (tx, _rx) = broadcast::channel::<i32>(1);
// the cloned `Tx` is dropped right away
let weak_tx = tx.clone().downgrade();
drop(tx);
assert!(weak_tx.upgrade().is_none());
}
// Tests that `downgrade` does not change the `strong_count` of the channel.
#[test]
fn test_tx_count_weak_sender() {
let (tx, _rx) = broadcast::channel::<i32>(1);
let tx_weak = tx.downgrade();
let tx_weak2 = tx.downgrade();
assert_eq!(tx.strong_count(), 1);
assert_eq!(tx.weak_count(), 2);
drop(tx);
assert!(tx_weak.upgrade().is_none());
assert!(tx_weak2.upgrade().is_none());
assert_eq!(tx_weak.strong_count(), 0);
assert_eq!(tx_weak.weak_count(), 2);
}
#[tokio::test]
async fn test_rx_is_closed_when_dropping_all_senders_except_weak_senders() {
let (tx, rx) = broadcast::channel::<()>(10);
let weak_sender = tx.clone().downgrade();
drop(tx);
// is_closed should return true after dropping all senders except for a weak sender.
// The strong count should be 0 while the weak count should remain at 1.
assert_eq!(weak_sender.strong_count(), 0);
assert_eq!(weak_sender.weak_count(), 1);
assert!(rx.is_closed());
}
#[tokio::test]
async fn sender_strong_count_when_cloned() {
let (tx, rx) = broadcast::channel::<()>(1);
let tx2 = tx.clone();
assert_eq!(tx.strong_count(), 2);
assert_eq!(tx2.strong_count(), 2);
assert_eq!(rx.sender_strong_count(), 2);
}
#[tokio::test]
async fn sender_weak_count_when_downgraded() {
let (tx, _rx) = broadcast::channel::<()>(1);
let weak = tx.downgrade();
assert_eq!(tx.weak_count(), 1);
assert_eq!(weak.weak_count(), 1);
}
#[tokio::test]
async fn sender_strong_count_when_dropped() {
let (tx, rx) = broadcast::channel::<()>(1);
let tx2 = tx.clone();
drop(tx2);
assert_eq!(tx.strong_count(), 1);
assert_eq!(rx.sender_strong_count(), 1);
}
#[tokio::test]
async fn sender_weak_count_when_dropped() {
let (tx, rx) = broadcast::channel::<()>(1);
let weak = tx.downgrade();
drop(weak);
assert_eq!(tx.weak_count(), 0);
assert_eq!(rx.sender_weak_count(), 0);
}
#[tokio::test]
async fn sender_strong_and_weak_conut() {
let (tx, rx) = broadcast::channel::<()>(1);
let tx2 = tx.clone();
let weak = tx.downgrade();
let weak2 = tx2.downgrade();
assert_eq!(tx.strong_count(), 2);
assert_eq!(tx2.strong_count(), 2);
assert_eq!(weak.strong_count(), 2);
assert_eq!(weak2.strong_count(), 2);
assert_eq!(rx.sender_strong_count(), 2);
assert_eq!(tx.weak_count(), 2);
assert_eq!(tx2.weak_count(), 2);
assert_eq!(weak.weak_count(), 2);
assert_eq!(weak2.weak_count(), 2);
assert_eq!(rx.sender_weak_count(), 2);
drop(tx2);
drop(weak2);
assert_eq!(tx.strong_count(), 1);
assert_eq!(weak.strong_count(), 1);
assert_eq!(rx.sender_strong_count(), 1);
assert_eq!(tx.weak_count(), 1);
assert_eq!(weak.weak_count(), 1);
assert_eq!(rx.sender_weak_count(), 1);
}
|
