small cleanups

[stockfish] / src / position.cpp

diff --git a/src/position.cpp b/src/position.cpp
index 5efd9c42a5eb351df1c043ea0b1e25a84b28f935..f5ff3da1862b29cf40d75a4b55e5c86ca1d3f8f3 100644 (file)
--- a/src/position.cpp
+++ b/src/position.cpp
@@ -306,7 +306,7 @@ void Position::set_castling_right(Color c, Square rfrom) {
   Square rto = relative_square(c, cr & KING_SIDE ? SQ_F1 : SQ_D1);
 
   castlingPath[cr] =   (between_bb(rfrom, rto) | between_bb(kfrom, kto) | rto | kto)
-                    & ~(square_bb(kfrom) | rfrom);
+                    & ~(kfrom | rfrom);
 }
 
 
@@ -375,11 +375,13 @@ void Position::set_state(StateInfo* si) const {
 
 Position& Position::set(const string& code, Color c, StateInfo* si) {
 
-  assert(code.length() > 0 && code.length() < 8);
   assert(code[0] == 'K');
 
   string sides[] = { code.substr(code.find('K', 1)),      // Weak
-                     code.substr(0, code.find('K', 1)) }; // Strong
+                     code.substr(0, std::min(code.find('v'), code.find('K', 1))) }; // Strong
+
+  assert(sides[0].length() > 0 && sides[0].length() < 8);
+  assert(sides[1].length() > 0 && sides[1].length() < 8);
 
   std::transform(sides[c].begin(), sides[c].end(), sides[c].begin(), tolower);
 
@@ -589,7 +591,7 @@ bool Position::pseudo_legal(const Move m) const {
       if (   !(attacks_from<PAWN>(from, us) & pieces(~us) & to) // Not a capture
           && !((from + pawn_push(us) == to) && empty(to))       // Not a single push
           && !(   (from + 2 * pawn_push(us) == to)              // Not a double push
-               && (rank_of(from) == relative_rank(us, RANK_2))
+               && (relative_rank(us, from) == RANK_2)
                && empty(to)
                && empty(to - pawn_push(us))))
           return false;
@@ -664,7 +666,7 @@ bool Position::gives_check(Move m) const {
   case CASTLING:
   {
       Square kfrom = from;
-      Square rfrom = to; // Castling is encoded as 'King captures the rook'
+      Square rfrom = to; // Castling is encoded as 'king captures the rook'
       Square kto = relative_square(sideToMove, rfrom > kfrom ? SQ_G1 : SQ_C1);
       Square rto = relative_square(sideToMove, rfrom > kfrom ? SQ_F1 : SQ_D1);
 
@@ -1119,10 +1121,7 @@ bool Position::is_draw(int ply) const {
 
   // Return a draw score if a position repeats once earlier but strictly
   // after the root, or repeats twice before or at the root.
-  if (st->repetition && st->repetition < ply)
-      return true;
-
-  return false;
+  return st->repetition && st->repetition < ply;
 }