Initial implementation of CheckingPieces and Position::checking_pieces()

position/src/check.rs

@@ -0,0 +1,29 @@
+// Eryn Wells <eryn@erynwells.me>
+
+use chessfriend_bitboard::BitBoard;
+
+pub struct CheckingPieces {
+    pawn: BitBoard,
+    knight: BitBoard,
+    bishop: BitBoard,
+    rook: BitBoard,
+    queen: BitBoard,
+}
+
+impl CheckingPieces {
+    pub(crate) fn new(
+        pawn: BitBoard,
+        knight: BitBoard,
+        bishop: BitBoard,
+        rook: BitBoard,
+        queen: BitBoard,
+    ) -> CheckingPieces {
+        CheckingPieces {
+            pawn,
+            knight,
+            bishop,
+            rook,
+            queen,
+        }
+    }
+}