White pawn fix

diff --git a/src/chess.lua b/src/chess.lua
index 7d436222a5265bfefb72e0eab3a2164272f8657c..1089da521a0636c15a0c2d5c2f99eea221c485aa 100644 (file)
--- a/src/chess.lua
+++ b/src/chess.lua
@@ -161,6 +161,26 @@ function realchess.move(pos, from_list, from_index, to_list, to_index, _, player
                        else
                                return 0
                        end
+
+                       -- if x not changed,
+                       --   ensure that destination cell is empty
+                       -- elseif x changed one unit left or right
+                       --   ensure the pawn is killing opponent piece
+                       -- else
+                       --   move is not legal - abort
+
+                       if from_x == to_x then
+                               if pieceTo ~= "" then
+                                       return 0
+                               end
+                       elseif from_x - 1 == to_x or from_x + 1 == to_x then
+                               if not pieceTo:find("black") then
+                                       return 0
+                               end
+                       else
+                               return 0
+                       end
+
                elseif thisMove == "black" then
                        local pawnBlackMove = inv:get_stack(from_list, xy_to_index(from_x, from_y + 1)):get_name()
                        -- black pawns can go down only