Vendor dependencies

Let's see how I like this workflow.

vendor/tokio/tests/macros_join.rs

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+#![cfg(feature = "macros")]
+#![allow(clippy::blacklisted_name)]
+use std::sync::Arc;
+
+#[cfg(tokio_wasm_not_wasi)]
+#[cfg(target_pointer_width = "64")]
+use wasm_bindgen_test::wasm_bindgen_test as test;
+#[cfg(tokio_wasm_not_wasi)]
+use wasm_bindgen_test::wasm_bindgen_test as maybe_tokio_test;
+
+#[cfg(not(tokio_wasm_not_wasi))]
+use tokio::test as maybe_tokio_test;
+
+use tokio::sync::{oneshot, Semaphore};
+use tokio_test::{assert_pending, assert_ready, task};
+
+#[maybe_tokio_test]
+async fn sync_one_lit_expr_comma() {
+    let foo = tokio::join!(async { 1 },);
+
+    assert_eq!(foo, (1,));
+}
+
+#[maybe_tokio_test]
+async fn sync_one_lit_expr_no_comma() {
+    let foo = tokio::join!(async { 1 });
+
+    assert_eq!(foo, (1,));
+}
+
+#[maybe_tokio_test]
+async fn sync_two_lit_expr_comma() {
+    let foo = tokio::join!(async { 1 }, async { 2 },);
+
+    assert_eq!(foo, (1, 2));
+}
+
+#[maybe_tokio_test]
+async fn sync_two_lit_expr_no_comma() {
+    let foo = tokio::join!(async { 1 }, async { 2 });
+
+    assert_eq!(foo, (1, 2));
+}
+
+#[maybe_tokio_test]
+async fn two_await() {
+    let (tx1, rx1) = oneshot::channel::<&str>();
+    let (tx2, rx2) = oneshot::channel::<u32>();
+
+    let mut join = task::spawn(async {
+        tokio::join!(async { rx1.await.unwrap() }, async { rx2.await.unwrap() })
+    });
+
+    assert_pending!(join.poll());
+
+    tx2.send(123).unwrap();
+    assert!(join.is_woken());
+    assert_pending!(join.poll());
+
+    tx1.send("hello").unwrap();
+    assert!(join.is_woken());
+    let res = assert_ready!(join.poll());
+
+    assert_eq!(("hello", 123), res);
+}
+
+#[test]
+#[cfg(target_pointer_width = "64")]
+fn join_size() {
+    use futures::future;
+    use std::mem;
+
+    let fut = async {
+        let ready = future::ready(0i32);
+        tokio::join!(ready)
+    };
+    assert_eq!(mem::size_of_val(&fut), 32);
+
+    let fut = async {
+        let ready1 = future::ready(0i32);
+        let ready2 = future::ready(0i32);
+        tokio::join!(ready1, ready2)
+    };
+    assert_eq!(mem::size_of_val(&fut), 40);
+}
+
+async fn non_cooperative_task(permits: Arc<Semaphore>) -> usize {
+    let mut exceeded_budget = 0;
+
+    for _ in 0..5 {
+        // Another task should run after this task uses its whole budget
+        for _ in 0..128 {
+            let _permit = permits.clone().acquire_owned().await.unwrap();
+        }
+
+        exceeded_budget += 1;
+    }
+
+    exceeded_budget
+}
+
+async fn poor_little_task(permits: Arc<Semaphore>) -> usize {
+    let mut how_many_times_i_got_to_run = 0;
+
+    for _ in 0..5 {
+        let _permit = permits.clone().acquire_owned().await.unwrap();
+        how_many_times_i_got_to_run += 1;
+    }
+
+    how_many_times_i_got_to_run
+}
+
+#[tokio::test]
+async fn join_does_not_allow_tasks_to_starve() {
+    let permits = Arc::new(Semaphore::new(1));
+
+    // non_cooperative_task should yield after its budget is exceeded and then poor_little_task should run.
+    let (non_cooperative_result, little_task_result) = tokio::join!(
+        non_cooperative_task(Arc::clone(&permits)),
+        poor_little_task(permits)
+    );
+
+    assert_eq!(5, non_cooperative_result);
+    assert_eq!(5, little_task_result);
+}
+
+#[tokio::test]
+async fn a_different_future_is_polled_first_every_time_poll_fn_is_polled() {
+    let poll_order = Arc::new(std::sync::Mutex::new(vec![]));
+
+    let fut = |x, poll_order: Arc<std::sync::Mutex<Vec<i32>>>| async move {
+        for _ in 0..4 {
+            {
+                let mut guard = poll_order.lock().unwrap();
+
+                guard.push(x);
+            }
+
+            tokio::task::yield_now().await;
+        }
+    };
+
+    tokio::join!(
+        fut(1, Arc::clone(&poll_order)),
+        fut(2, Arc::clone(&poll_order)),
+        fut(3, Arc::clone(&poll_order)),
+    );
+
+    // Each time the future created by join! is polled, it should start
+    // by polling a different future first.
+    assert_eq!(
+        vec![1, 2, 3, 2, 3, 1, 3, 1, 2, 1, 2, 3],
+        *poll_order.lock().unwrap()
+    );
+}