Fixed bug in which castling was not possible on the queen side

jean-bovet · Aug 1, 2021 · 7a9953d · 7a9953d
1 parent 984cf71
commit 7a9953d
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Showing 2 changed files with 27 additions and 7 deletions.
diff --git a/BChessTests/MovesTests.cpp b/BChessTests/MovesTests.cpp
@@ -170,12 +170,22 @@ TEST_F(MovesTests, WhiteKingCastling) {
                 }, "e1"
                 );
 
-    // Black rook attacking b1 (so no queen side castling possible)
+    // Black rook attacking b1 (queen side castling possible)
     assertMoves("1r2k3/8/8/8/8/8/3PPP2/R3K2R w KQ - 0 1",
                 {
                  "1r2k3/8/8/8/8/8/3PPP2/R4RK1 b - - 1 1", // King side
-                 "1r2k3/8/8/8/8/8/3PPP2/R2K3R b - - 1 1",
-                 "1r2k3/8/8/8/8/8/3PPP2/R4K1R b - - 1 1"
+                 "1r2k3/8/8/8/8/8/3PPP2/R2K3R b - - 1 1", // Queen side
+                 "1r2k3/8/8/8/8/8/3PPP2/R4K1R b - - 1 1", // King side
+                 "1r2k3/8/8/8/8/8/3PPP2/2KR3R b - - 1 1", // Queen side
+                }, "e1"
+                );
+
+    // Black rook attacking b2 (no queen side castling possible)
+    assertMoves("2r1k3/8/8/8/8/8/3PPP2/R3K2R w KQ - 0 1",
+                {
+                 "2r1k3/8/8/8/8/8/3PPP2/R2K3R b - - 1 1", // Queen side
+                 "2r1k3/8/8/8/8/8/3PPP2/R4K1R b - - 1 1", // King side
+                 "2r1k3/8/8/8/8/8/3PPP2/R4RK1 b - - 1 1", // King side
                 }, "e1"
                 );
 }
@@ -203,12 +213,22 @@ TEST_F(MovesTests, BlackKingCastling) {
                 }, "e8"
                 );
 
-    // White rook attacking b8 (so no queen side castling possible)
+    // White rook attacking b8 (queen side castling possible)
     assertMoves("r3k2r/3ppp2/8/8/8/8/8/1R2K3 b kq - 0 1",
                 {
                  "r4rk1/3ppp2/8/8/8/8/8/1R2K3 w - - 1 2", // King side
                  "r4k1r/3ppp2/8/8/8/8/8/1R2K3 w - - 1 2",
-                 "r2k3r/3ppp2/8/8/8/8/8/1R2K3 w - - 1 2"
+                 "r2k3r/3ppp2/8/8/8/8/8/1R2K3 w - - 1 2", // Queen side
+                 "2kr3r/3ppp2/8/8/8/8/8/1R2K3 w - - 1 2"
+                }, "e8"
+                );
+
+    // White rook attacking c8 (so no queen side castling possible)
+    assertMoves("r3k2r/3ppp2/8/8/8/8/8/2R1K3 b kq - 0 1",
+                {
+                 "r2k3r/3ppp2/8/8/8/8/8/2R1K3 w - - 1 2", // Queen side
+                 "r4k1r/3ppp2/8/8/8/8/8/2R1K3 w - - 1 2", // King side
+                 "r4rk1/3ppp2/8/8/8/8/8/2R1K3 w - - 1 2"
                 }, "e8"
                 );
 }

diff --git a/Shared/Engine/ChessMoveGenerator.cpp b/Shared/Engine/ChessMoveGenerator.cpp
@@ -280,7 +280,7 @@ void ChessMoveGenerator::generateKingsMoves(ChessBoard &board, Color color, Move
             }
             if (board.whiteCanCastleQueenSide) {
                 Bitboard kingMoves = 1 << (square-1) | 1 << (square-2) | 1 << (square-3);
-                if ((kingMoves & emptySquares) == kingMoves && !board.isAttacked(square-1, otherColor) && !board.isAttacked(square-2, otherColor) && !board.isAttacked(square-3, otherColor)) {
+                if ((kingMoves & emptySquares) == kingMoves && !board.isAttacked(square-1, otherColor) && !board.isAttacked(square-2, otherColor)) {
                     moveList.addMove(board, createCastling(square, square-2, color, KING));
                     if (mode == Mode::firstMoveOnly && moveList.count > 0) return;
                 }
@@ -296,7 +296,7 @@ void ChessMoveGenerator::generateKingsMoves(ChessBoard &board, Color color, Move
             }
             if (board.blackCanCastleQueenSide) {
                 Bitboard kingMoves = 1UL << (square-1) | 1UL << (square-2) | 1UL << (square-3);
-                if ((kingMoves & emptySquares) == kingMoves && !board.isAttacked(square-1, otherColor) && !board.isAttacked(square-2, otherColor) && !board.isAttacked(square-3, otherColor)) {
+                if ((kingMoves & emptySquares) == kingMoves && !board.isAttacked(square-1, otherColor) && !board.isAttacked(square-2, otherColor)) {
                     moveList.addMove(board, createCastling(square, square-2, color, KING));
                     if (mode == Mode::firstMoveOnly && moveList.count > 0) return;
                 }