test: add test for NetworkCoordinate::estimate_rtt

Signed-off-by: Stephen Waits <steve@waits.net>

src/network_coordinate.rs

@@ -304,4 +304,16 @@ mod tests {
         let t = serde_json::to_string(&a);
         assert_eq!(t.as_ref().unwrap(), s);
     }
+
+    #[test]
+    fn test_estimated_rtt() {
+        // start with JSON, deserialize it
+        let s = "{\"position\":[{\"inner\":[1.5,0.5,2.0]},25.0],\"error\":1.0}";
+        let a: NetworkCoordinate<3> = serde_json::from_str(s).unwrap();
+        let s = "{\"position\":[{\"inner\":[-1.5,-0.5,-2.0]},50.0],\"error\":1.0}";
+        let b: NetworkCoordinate<3> = serde_json::from_str(s).unwrap();
+
+        let estimate = a.estimated_rtt(&b);
+        assert_approx_eq!(estimate.as_secs_f32(), 0.080_099);
+    }
 }