bitboard: split test

src/repr/bitboard.rs

@@ -118,14 +118,19 @@ mod test {
     use super::*;
 
     #[test]
-    fn set_and_get() {
-        let mut b = BitBoard::new();
+    fn init_empty() {
+        let b = BitBoard::new();
         for c in 0..Board::AREA.0 {
             assert!(
                 !b.get(CoordPair(c)),
                 "A just-initalized BitBoard should be completely empty"
             )
         }
+    }
+
+    #[test]
+    fn set_and_get() {
+        let mut b = BitBoard::new();
 
         assert!(!b.get((2, 4).into()));
         b.set((2, 4).into(), true);