Fix shako castling

Consider pinned rook scenario like in chess960.

Closes #453.

diff --git a/src/position.cpp b/src/position.cpp
index 00e171f..64ad96a 100644 (file)
--- a/src/position.cpp
+++ b/src/position.cpp
@@ -1092,7 +1092,7 @@ bool Position::legal(Move m) const {
 
       // In case of Chess960, verify if the Rook blocks some checks
       // For instance an enemy queen in SQ_A1 when castling rook is in SQ_B1.
-      return !chess960 || !attackers_to(to, pieces() ^ to_sq(m), ~us);
+      return !attackers_to(to, pieces() ^ to_sq(m), ~us);
   }
 
   Bitboard occupied = (type_of(m) != DROP ? pieces() ^ from : pieces()) | to;

diff --git a/tests/perft.sh b/tests/perft.sh
index 93b0ffb..fe585e9 100755 (executable)
--- a/tests/perft.sh
+++ b/tests/perft.sh
@@ -145,6 +145,7 @@ if [[ $1 == "all" ||  $1 == "largeboard" ]]; then
   expect perft.exp centaur startpos 3 24490 > /dev/null
   expect perft.exp shako "fen 4kc3c/ernbq1b1re/ppp3p1pp/3p2pp2/4p5/5P4/2PN2P3/PP1PP2PPP/ER1BQKBNR1/5C3C w KQ - 0 9" 3 26325 > /dev/null
   expect perft.exp shako "fen 4ncr1k1/1cr2P4/pp2p2pp1/P7PN/2Ep1p4/B3P1eN2/2P1n1P3/1B1P1K4/9p/5C2CR w - - 0 1" 3 180467 > /dev/null
+  expect perft.exp shako "fen r5k3/4q2c2/1ebppnp3/1pp3BeEQ/10/2PE2P3/1P3P4/5NP2P/rR3KB3/7C2 w Q - 3 35" 2 4940 > /dev/null
   expect perft.exp xiangqi startpos 4 3290240 > /dev/null
   expect perft.exp xiangqi "fen 1rbaka2R/5r3/6n2/2p1p1p2/4P1bP1/PpC3Bc1/1nPR2P2/2N2AN2/1c2K1p2/2BAC4 w - - 0 1" 4 4485547 > /dev/null
   expect perft.exp xiangqi "fen 4kcP1N/8n/3rb4/9/9/9/9/3p1A3/4K4/5CB2 w - - 0 1" 4 92741 > /dev/null