Added testing of tokio when running cargo test

tests/tokio_testing.rs

@@ -0,0 +1,62 @@
+use futures::stream::StreamExt;
+use tokio::task;
+use std::sync::{Arc, Mutex};
+use r2r;
+
+#[tokio::test(flavor = "multi_thread")]
+async fn tokio_testing() -> Result<(), Box<dyn std::error::Error>> {
+    let ctx = r2r::Context::create()?;
+    let mut node = r2r::Node::create(ctx, "testnode", "")?;
+    let mut s_the_no = node.subscribe::<r2r::std_msgs::msg::Int32>("/the_no")?;
+    let mut s_new_no = node.subscribe::<r2r::std_msgs::msg::Int32>("/new_no")?;
+    let p_the_no = node.create_publisher::<r2r::std_msgs::msg::Int32>("/the_no")?;
+    let p_new_no = node.create_publisher::<r2r::std_msgs::msg::Int32>("/new_no")?;
+    let state = Arc::new(Mutex::new(0));
+
+    task::spawn(async move {
+        (0..10).for_each(|i| {
+            p_the_no.publish(&r2r::std_msgs::msg::Int32{data: i}).unwrap();
+        });
+    });
+
+    task::spawn(async move {
+        loop {
+            match s_the_no.next().await {
+                Some(msg) => {
+                    p_new_no.publish(&r2r::std_msgs::msg::Int32{data: msg.data + 10}).unwrap();
+                },
+                None => break,
+            }
+        }
+    });
+
+    let s = state.clone();
+    task::spawn(async move {
+        loop {
+            match s_new_no.next().await {
+                Some(msg) => {
+                    let i = msg.data;
+                    if i==19 {
+                        *s.lock().unwrap() = 19;
+                    }
+                },
+                None => break,
+            }
+        }
+    });
+
+    let handle = std::thread::spawn(move || {
+        for _ in 1..=30 {
+            node.spin_once(std::time::Duration::from_millis(100));
+            let x = state.lock().unwrap();
+            if *x == 19 {
+                break;
+            }
+        };
+
+        state.lock().unwrap().clone()
+    });
+    let x =  handle.join().unwrap();
+    assert_eq!(x, 19);
+    Ok(())
+}