test: increase perft depth up to 3

1 files changed, 19 insertions, 12 deletions

diff --git a/src/board.rs b/src/board.rs
index d3c1666..7b17aad 100644
--- a/src/board.rs
+++ b/src/board.rs
@@ -286,9 +286,9 @@ impl Board {
         self.ply -= 1;
     }
 
-    fn perft(&mut self, depth: u8, print: bool) -> u64 {
+    fn perft(&mut self, depth: u8, print: bool) -> (u64, u64) {
         if depth == 0 {
-            return 1 // This a leaf, exactly one node
+            return (1, 0) // This a leaf, exactly one node
         }
         let color = self.color_to_move();
 
@@ -300,16 +300,22 @@ impl Board {
         }
 
         let mut total = 0;
+        let mut tactical = 0;
 
         for mov in moves {
             let captured_piece = self.make_move(mov);
-            if print {
-                println!("{:?}", mov);
-                self.print();
-            }
             // King can not be in check after our own move
             if !self.is_king_in_check(color) {
-                total += self.perft(depth - 1, print);
+                if print {
+                    println!("{:?}", mov);
+                    self.print();
+                }
+                if captured_piece.is_some() {
+                    tactical += 1;
+                }
+                let (children_total, children_tactical) = self.perft(depth - 1, print);
+                total += children_total;
+                tactical += children_tactical;
             }
             self.unmake_move(mov, captured_piece);
         }
@@ -318,7 +324,7 @@ impl Board {
             println!("Found {} nodes in this subtree (depth {})", total, depth);
         }
 
-        total
+        (total, tactical)
     }
 
     fn is_square_attacked(&self, square: Square, attacker_color: Color) -> bool {
@@ -504,10 +510,11 @@ mod tests {
         let fen = String::from(DEFAULT_FEN);
         let mut board = Board::from_FEN(fen);
 
-        assert_eq!(board.perft(0, false), 1);
-        assert_eq!(board.perft(1, false), 20);
-        assert_eq!(board.perft(2, false), 400);
-        // TODO: assert_eq!(board.perft(3, false), 8902);
+        assert_eq!(board.perft(0, false), (1, 0));
+        assert_eq!(board.perft(1, false), (20, 0));
+        assert_eq!(board.perft(2, false), (400, 0));
+        assert_eq!(board.perft(3, false), (8902, 34));
+        // assert_eq!(board.perft(4, false), (197281, 1576));
     }
 
     #[test]