fix: fix coroutine tests on windows

tests/test_coroutine.rs

@@ -1,11 +1,8 @@
 #![cfg(feature = "macros")]
-use futures::channel::oneshot;
-use futures::future::poll_fn;
-use pyo3::prelude::*;
-use pyo3::py_run;
-use std::task::Poll;
-use std::thread;
-use std::time::Duration;
+use std::{task::Poll, thread, time::Duration};
+
+use futures::{channel::oneshot, future::poll_fn};
+use pyo3::{prelude::*, py_run};
 
 #[path = "../src/tests/common.rs"]
 mod common;
@@ -59,7 +56,12 @@ async fn sleep(seconds: f64) -> usize {
 fn sleep_coroutine() {
     Python::with_gil(|gil| {
         let sleep = wrap_pyfunction!(sleep, gil).unwrap();
-        let test = "import asyncio; assert asyncio.run(sleep(0.1)) == 42";
+        let test = r#"
+        import asyncio, sys
+        if sys.platform == "win32":
+            asyncio.set_event_loop_policy(asyncio.WindowsSelectorEventLoopPolicy())
+        assert asyncio.run(sleep(0.1)) == 42
+        "#;
         py_run!(gil, sleep, test);
     })
 }
@@ -69,7 +71,9 @@ fn cancelled_coroutine() {
     Python::with_gil(|gil| {
         let sleep = wrap_pyfunction!(sleep, gil).unwrap();
         let test = r#"
-        import asyncio;
+        import asyncio, sys
+        if sys.platform == "win32":
+            asyncio.set_event_loop_policy(asyncio.WindowsSelectorEventLoopPolicy())
         async def main():
             task = asyncio.create_task(sleep(1))
             await asyncio.sleep(0)