test + cleanup agent direction code

src/agent.rs

@@ -67,20 +67,19 @@ impl Agent {
         let right = buf.get_buf(xr, yr);
 
         // Rotate and move logic
-        let mut rng = rand::thread_rng();
+        let direction = if (center > left) && (center > right) {
-        let mut direction: f32 = 0.0;
+            0.0
-
-        if (center > left) && (center > right) {
-            direction = 0.0;
         } else if (center < left) && (center < right) {
-            direction = *[-1.0, 1.0]
+            *[-1.0, 1.0]
-                .choose(&mut rng)
+                .choose(&mut rand::thread_rng())
-                .expect("unable to choose random direction");
+                .expect("unable to choose random direction")
         } else if left < right {
-            direction = 1.0;
+            1.0
         } else if right < left {
-            direction = -1.0;
+            -1.0
-        }
+        } else {
+            0.0
+        };
 
         let delta_angle = rotation_angle * direction;
 

src/util.rs

@@ -11,3 +11,15 @@ pub const fn index(width: usize, height: usize, x: f32, y: f32) -> usize {
     let j = (y + height as f32) as usize & (height - 1);
     j * width + i
 }
+
+#[cfg(test)]
+mod test {
+    use super::*;
+
+    #[test]
+    fn wrap_test() {
+        assert_eq!(wrap(1.1, 1.0), 0.100000024);
+        assert_eq!(wrap(0.5, 1.0), 0.5);
+        assert_eq!(wrap(-1.0, 2.0), 1.0);
+    }
+}