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chess: updating documentation
Documentation is now set for every method with complete parameters. Also all global variables and constants as well as types are documented.
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TiynGER
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chess.nim
220
chess.nim
@ -10,9 +10,8 @@ type
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## `Board` saves the position of the chess pieces.
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Moved* = array[0..119, bool] ## \
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## `Moved` saves the position of squares a piece moved on or from.
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CastleRights = tuple
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# `CastleRights` contains the rights to castling for each player.
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## `CastleRights` contains the rights to castling for each player.
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wk: bool # `wk` describes White kingside castle
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wq: bool # `wq` describes White queenside castle
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bk: bool # `bk` describes Black kingside castle
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@ -32,8 +31,8 @@ type
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color: Color
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prom: int
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PieceAmount = tuple
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# `PieceAmount` describes the number of pieces of a certain type a/both
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# player/s has/have.
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## `PieceAmount` describes the number of pieces of a certain type a/both
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## player/s has/have.
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p: int # `p` describes the amount of pawns.
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n: int # `n` describes the amount of knights.
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b: int # `b` describes the amount of bishops.
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@ -41,69 +40,79 @@ type
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q: int # `q` describes the amount of queens.
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const
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Block* = 999 ## \
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Block* = 999 ## \
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## `Block` is the value assigned to empty blocked fields in a board.
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WPawn* = 1
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## `WPawn` is the value assigned to a square in a board with a white pawn.
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WKnight* = 2 ## \
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WKnight* = 2 ## \
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## `WKnight` is the value assigned to a square in a board with a white
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## knight.
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WBishop* = 3 ## \
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WBishop* = 3 ## \
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## `WBishop` is the value assigned to a square in a board with a white
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## bishop.
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WRook* = 4 ## \
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WRook* = 4 ## \
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## `WRook` is the value assigned to a square in a board with a white rook.
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WQueen* = 5 ## \
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WQueen* = 5 ## \
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## `WQueen` is the value assigned to a square in a board with a white
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## queen.
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WKing* = 6 ## \
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WKing* = 6 ## \
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## `WKing` is the value assigned to a square in a board with a white king.
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WEnPassant* = 7 ## \
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WEnPassant* = 7 ## \
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## `WEnPassant` is assigned to a square in a board with an invisible white
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## en passant pawn.
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BPawn* = -WPawn ## \
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BPawn* = -WPawn ## \
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## `BPawn` is the value assigned to a square in a board with a black pawn.
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BKnight* = -WKnight ## \
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BKnight* = -WKnight ## \
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## `BKnight` is the value assigned to a square in a board with a black\
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## knight.
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BBishop* = -WBishop ## \
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BBishop* = -WBishop ## \
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## `BBishop` is the value assigned to a square in a board with a black\
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## bishop.
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BRook* = -WRook ## \
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BRook* = -WRook ## \
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## `BRook` is the value assigned to a square in a board with a black rook.
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BQueen* = -WQueen ## \
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BQueen* = -WQueen ## \
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## `BQueen` is the value assigned to a square in a board with a black queen.
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BKing* = -WKing ## \
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BKing* = -WKing ## \
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## `BKing` is the value assigned to a square in a board with a black king.
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BEnPassant* = -WEnPassant ## \
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BEnPassant* = -WEnPassant ## \
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## `BEnPassant` is assigned to a square in a board with an invisible black
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## en passant pawn.
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# Directions of squares from whites perspective.
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N = 10 # move up
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S = -N # Move down
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W = 1 # Move left
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E = -W # Move right
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N = 10 ## `N` describes a move a field up the board from whites perspective.
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S = -N ## `S` describes a move a field down the board from whites perspective.
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W = 1 ## `W` describes a move a field to the left from whites perspective.
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E = -W ## `E` describes a move a field to the right from whites perspective.
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# Directions for the pieces. Special moves are in separate arrays.
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Knight_Moves = [N+N+E, N+N+W, E+E+N, E+E+S, S+S+E, S+S+W, W+W+N, W+W+S]
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Bishop_Moves = [N+E, N+W, S+E, S+W]
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Rook_Moves = [N, E, S, W]
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Queen_Moves = [N, E, S, W, N+E, N+W, S+E, S+W]
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King_Moves = [N, E, S, W, N+E, N+W, S+E, S+W]
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King_Moves_White_Castle = [E+E, W+W]
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Pawn_Moves_White = [N]
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Pawn_Moves_White_Double = [N+N]
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Pawn_Moves_White_Attack = [N+E, N+W]
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# Material as PieceAmount where a forced checkmate is not possible.
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InsufficientMaterial: array[4,PieceAmount] = [
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(0, 0, 0, 0, 0), # only kings
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(0, 0, 1, 0, 0), # knight only
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(0, 1, 0, 0, 0), # bishop only
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(0, 2, 0, 0, 0) # 2 knights
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]
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Knight_Moves = [N+N+E, N+N+W, E+E+N, E+E+S, S+S+E, S+S+W, W+W+N, W+W+S] ## \
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## `Knight_Moves` describes the possible knight moves.
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Bishop_Moves = [N+E, N+W, S+E, S+W] ## \
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## `Bishop_Moves` describes the possible 1 field distance bishop moves.
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Rook_Moves = [N, E, S, W] ## \
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## `Rook_Moves` describes the possible 1 field distance rook moves.
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Queen_Moves = [N, E, S, W, N+E, N+W, S+E, S+W] ## \
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## `Queen_Moves` describes the possible 1 field distance queen moves.
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King_Moves = [N, E, S, W, N+E, N+W, S+E, S+W] ## \
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## `King_Moves` describes the possible 1 field distance king moves.
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King_Moves_White_Castle = [E+E, W+W] ## \
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## `King_Moves` describes the possible king moves for castling.
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Pawn_Moves_White = [N] ## \
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## `Pawn_Moves_White` describes the possible 1 field distance pawn moves
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## from whites perspective that are not attacks.
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Pawn_Moves_White_Double = [N+N] ## \
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## `Pawn_Moves_White_Double` describes the possible pawn 2 field distance
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## moves from whites perspective.
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Pawn_Moves_White_Attack = [N+E, N+W] ## \
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## `Pawn_Moves_White` describes the possible 1 field distance pawn moves
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## from whites perspective that are ttacks.
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InsufficientMaterial: array[4, PieceAmount] = [
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(0, 0, 0, 0, 0), # only kings
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(0, 0, 1, 0, 0), # knight only
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(0, 1, 0, 0, 0), # bishop only
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(0, 2, 0, 0, 0) # 2 knights
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] ## `InsufficientMaterial` describes the pieces where no checkmate can be
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## forced.
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let
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# Representation of the pieces by ID.
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PieceChar = {
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0: " ",
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WPawn: "P",
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@ -120,8 +129,8 @@ let
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BQueen: "q",
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BKing: "k",
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BEnPassant: " ",
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}.newTable
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# Files on the chess board mapped to according integers.
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}.newTable ## \
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## `PieceChar` describes the representation for the pieceIDs for the cli.
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FileChar = {
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"a": 7,
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"b": 6,
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@ -131,10 +140,14 @@ let
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"f": 2,
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"g": 1,
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"h": 0
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}.newTable
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}.newTable ## \
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# `FileChar` maps the files of the chessboard to numbers for better
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# conversion.
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proc checkInsufficientMaterial(board: Board): bool =
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## Checks for combinations of pieces on a `board`, where no checkmate can be forced
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## Checks for combinations of pieces on a `board`, where no checkmate can be
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## forced.
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## Returns true if no player can force a checkmate to the other.
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var wp = 0
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var wn = 0
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var wb = 0
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@ -191,7 +204,8 @@ proc initBoard(): Board =
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return board
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proc initBoard(board: array[0..63, int]): Board =
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## Create and return a board with pieces in position of choice
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## Create and return a board with pieces in position of choice, described in
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## `board`.
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let board = [
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Block, Block, Block, Block, Block, Block, Block, Block, Block, Block,
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Block, Block, Block, Block, Block, Block, Block, Block, Block, Block,
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@ -229,6 +243,7 @@ proc initGame*(): Game =
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proc initGame*(board: array[0..63, int], color: Color): Game =
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## Create ad return a Game object based on a position of choice.
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## `board` describes the pieces, `color` the color that is about to move.
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let board = initBoard(board)
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let compare = initBoard()
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var moved = initMoved()
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@ -242,19 +257,22 @@ proc initGame*(board: array[0..63, int], color: Color): Game =
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return game
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proc getMove*(start: int, dest: int, prom: int, color: Color): Move =
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## Get a move object from `start` to `dest` with an eventual promition to `prom`
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## Get a move object of the `color` player from `start` to `dest` with an
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## eventual promition to `prom`.
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var move = Move(start: start, dest: dest, prom: prom * ord(color), color: color)
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if (WKnight > prom or WQueen < prom):
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move.prom = WQueen
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return move
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proc getMove*(start: int, dest: int, color: Color): Move =
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## Get a move object from `start` to `dest` with automatic promition to `queen`
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## Get a move object of the `color` player from `start` to `dest` with
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## automatic promition to queen.
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var move = Move(start: start, dest: dest, prom: WQueen * ord(color), color: color)
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return move
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proc echoBoard*(game: Game, color: Color) =
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## Prints out the given `board` with its pieces as characters and line indices from perspecive of `color`.
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## Prints out the given `board` with its pieces as characters and line
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## indices from perspecive of `color`.
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var line_str = ""
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if (color == Color.Black):
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for i in countup(0, len(game.board)-1):
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@ -276,21 +294,23 @@ proc echoBoard*(game: Game, color: Color) =
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echo "a b c d e f g h"
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proc fieldToInd*(file: string, line: int): int =
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## Calculate board index from `file` and `line` of a chess board.
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## Calculate and return board index from `file` and `line` of a chess board.
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## Returns -1 if the `field` was not input correct.
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try:
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return 1+(line+1)*10+FileChar[file]
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except IndexDefect, ValueError:
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return -1
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proc fieldToInd*(field: string): int =
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## Calculate board index from `field` of a chess board.
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## Calculate and return board index from `field` of a chess board.
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## Returns -1 if the `field` was not input correct.
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try:
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return fieldToInd($field[0], parseInt($field[1]))
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except IndexDefect, ValueError:
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return -1
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proc indToField*(ind: int): string =
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## Calculate field name from board index `ind`.
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## Calculate and returns field name from board index `ind`.
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let line = (int)ind/10-1
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let file_ind = (ind)%%10-1
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for file, i in FileChar:
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@ -298,7 +318,7 @@ proc indToField*(ind: int): string =
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return $file & $line
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proc genCastleRights(moved: Moved): CastleRights =
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## Generate rights to castle from given `moved`
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## Generate and return rights to castle from given `moved`
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let wk = not moved[fieldToInd("e1")] and not moved[fieldToInd("h1")]
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let wq = not moved[fieldToInd("e1")] and not moved[fieldToInd("a1")]
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let bk = not moved[fieldToInd("e8")] and not moved[fieldToInd("h8")]
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@ -306,7 +326,8 @@ proc genCastleRights(moved: Moved): CastleRights =
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return (wk, wq, bk, bq)
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proc notationToMove*(notation: string, color: Color): Move =
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## Convert simplified algebraic chess `notation` to a move object, color of player is `color`.
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## Convert and return simplified algebraic chess `notation` to a move object,
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## color of player is `color`.
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var move: Move
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var start = fieldToInd(notation[0..1])
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var dest = fieldToInd(notation[2..3])
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@ -327,7 +348,8 @@ proc notationToMove*(notation: string, color: Color): Move =
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return move
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proc genBishopDests(game: Game, field: int, color: Color): seq[int] =
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## Generate possible destinations for a bishop with specific `color` located at index `field` of `game`.
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## Generate possible destinations for a bishop with specific `color` located
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## at index `field` of `game`.
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## Returns a sequence of possible indices to move to.
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if (not field in game.board.low..game.board.high):
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return @[]
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@ -349,7 +371,8 @@ proc genBishopDests(game: Game, field: int, color: Color): seq[int] =
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return res
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proc genRookDests(game: Game, field: int, color: Color): seq[int] =
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## Generate possible destinations for a rook with specific `color` located at index `field` of `game`.
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## Generate possible destinations for a rook with specific `color` located at
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## index `field` of `game`.
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## Returns a sequence of possible indices to move to.
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if (not field in game.board.low..game.board.high):
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return @[]
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@ -371,7 +394,8 @@ proc genRookDests(game: Game, field: int, color: Color): seq[int] =
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return res
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proc genQueenDests(game: Game, field: int, color: Color): seq[int] =
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## Generate possible destinations for a queen with specific `color` located at index `field` of `game`.
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## Generate possible destinations for a queen with specific `color` located
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## at index `field` of `game`.
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## Returns a sequence of possible indices to move to.
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if (not field in game.board.low..game.board.high):
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return @[]
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@ -393,7 +417,8 @@ proc genQueenDests(game: Game, field: int, color: Color): seq[int] =
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return res
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proc genKingCastleDest(game: Game, field: int, color: Color): seq[int] =
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## Generate possible castle destinations for a king with specific `color` located at index `field` of `game`
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## Generate possible castle destinations for a king with specific `color`
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## located at index `field` of `game`
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## Returns a sequence of possible indices to move to.
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if (not field in game.board.low..game.board.high):
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return @[]
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@ -416,9 +441,9 @@ proc genKingCastleDest(game: Game, field: int, color: Color): seq[int] =
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res.add(dest)
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return res
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proc genKingDests(game: Game, field: int, color: Color): seq[int] =
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## Generate possible destinations for a king with specific `color` located at index `field` of `game`.
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## Generate possible destinations for a king with specific `color`
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## located at index `field` of `game`.
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## Returns a sequence of possible indices to move to.
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if (not field in game.board.low..game.board.high):
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return @[]
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@ -437,7 +462,8 @@ proc genKingDests(game: Game, field: int, color: Color): seq[int] =
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return res
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proc genKnightDests(game: Game, field: int, color: Color): seq[int] =
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## Generate possible destinations for a knight with specific `color` located at index `field` of `game`.
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## Generate possible destinations for a knight with specific `color` located
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## at index `field` of `game`.
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## Returns a sequence of possible indices to move to.
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if (not field in game.board.low..game.board.high):
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return @[]
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@ -455,7 +481,8 @@ proc genKnightDests(game: Game, field: int, color: Color): seq[int] =
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return res
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proc genPawnAttackDests(game: Game, field: int, color: Color): seq[int] =
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## Generate possible attack destinations for a pawn with specific `color` located at index `field` of `game`.
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## Generate possible attack destinations for a pawn with specific `color`
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## located at index `field` of `game`.
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## Returns a sequence of possible indices to move to.
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if (not field in game.board.low..game.board.high):
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return @[]
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@ -473,7 +500,8 @@ proc genPawnAttackDests(game: Game, field: int, color: Color): seq[int] =
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return res
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proc genPawnDoubleDests(game: Game, field: int, color: Color): seq[int] =
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## Generate possible double destinations for a pawn with specific `color` located at index `field` of `game`.
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## Generate possible double destinations for a pawn with specific `color`
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## located at index `field` of `game`.
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## Returns a sequence of possible indices to move to.
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if (not field in game.board.low..game.board.high):
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return @[]
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@ -492,7 +520,8 @@ proc genPawnDoubleDests(game: Game, field: int, color: Color): seq[int] =
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return res
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proc genPawnDests(game: Game, field: int, color: Color): seq[int] =
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## Generate possible destinations for a pawn with specific `color` located at index `field` of `game`.
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## Generate possible destinations for a pawn with specific `color` located at
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## index `field` of `game`.
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## Returns a sequence of possible indices to move to.
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if (not field in game.board.low..game.board.high):
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return @[]
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@ -513,14 +542,16 @@ proc genPawnDests(game: Game, field: int, color: Color): seq[int] =
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proc pieceOn(game: Game, color: Color, sequence: seq[int],
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pieceID: int): bool =
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## Check if a piece with `pieceID` of a given `color` is in a field described in a `sequence` in a `game`.
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## Returns true if the `PieceID` of a given `color` is in `sequence` else
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## wrong.
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for check in sequence:
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if game.board[check] == ord(color) * -1 * pieceID:
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return true
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return false
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proc isAttacked(game: Game, position: int, color: Color): bool =
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## Check if a field is attacked by the opposite of `color` in a `game`.
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## Returns true if a `position` in a `game` is attacked by the opposite
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## color of `color`.
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var attacked = false
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attacked = attacked or game.pieceOn(color, game.genPawnAttackDests(
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position, color), WPawn)
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@ -537,7 +568,7 @@ proc isAttacked(game: Game, position: int, color: Color): bool =
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return attacked
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proc isInCheck*(game: Game, color: Color): bool =
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## Check if the King of a given `color` is in check in a `game`.
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## Returns true if the king of a given `color` is in check in a `game`.
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var king_pos: int
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for i in countup(0, game.board.high):
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if game.board[i] == ord(color) * WKing:
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@ -545,9 +576,8 @@ proc isInCheck*(game: Game, color: Color): bool =
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return game.isAttacked(king_pos, color)
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|
||||
proc uncheckedMove(game: var Game, start: int, dest: int): bool {.discardable.} =
|
||||
## Moves a piece if possible from `start` position to `dest` position.
|
||||
## Doesnt check boundaries, checks, movement.
|
||||
## returns true if the piece moved, else false
|
||||
## Moves a piece if possible from `start` position to `dest` position in a
|
||||
## `game`.
|
||||
let piece = game.board[start]
|
||||
game.board[start] = 0
|
||||
game.board[dest] = piece
|
||||
@ -557,19 +587,21 @@ proc uncheckedMove(game: var Game, start: int, dest: int): bool {.discardable.}
|
||||
|
||||
proc moveLeadsToCheck(game: Game, start: int, dest: int,
|
||||
color: Color): bool =
|
||||
## Checks in a `game` if a move from `start` to `dest` puts the `color` king in check.
|
||||
## Returns true if a move from `start` to `dest` in a `game` puts the `color`
|
||||
## king in check.
|
||||
var check = game
|
||||
check.uncheckedMove(start, dest)
|
||||
return check.isInCheck(color)
|
||||
|
||||
proc removeEnPassant(board: var Board, color: Color): void =
|
||||
## Removes every en passant of given `color` from the `game`.
|
||||
## Removes every en passant of given `color` from the `board`.
|
||||
for field in board.low..board.high:
|
||||
if board[field] == ord(color) * WEnPassant:
|
||||
board[field] = 0
|
||||
|
||||
proc genLegalKnightMoves(game: Game, field: int, color: Color): seq[Move] =
|
||||
## Generates all legal knight moves starting from `field` in a `game` for a `color`.
|
||||
## Generates all legal knight moves in a `game` starting from `field` for a
|
||||
## `color`.
|
||||
if game.board[field] != WKnight * ord(color):
|
||||
return @[]
|
||||
var res = newSeq[Move]()
|
||||
@ -580,7 +612,8 @@ proc genLegalKnightMoves(game: Game, field: int, color: Color): seq[Move] =
|
||||
return res
|
||||
|
||||
proc genLegalBishopMoves(game: Game, field: int, color: Color): seq[Move] =
|
||||
## Generates all legal bishop moves starting from `field` in a `game` for a `color`.
|
||||
## Generates all legal bishop moves in a `game` starting from `field` for a
|
||||
## `color`.
|
||||
if game.board[field] != WBishop * ord(color):
|
||||
return @[]
|
||||
var res = newSeq[Move]()
|
||||
@ -591,7 +624,8 @@ proc genLegalBishopMoves(game: Game, field: int, color: Color): seq[Move] =
|
||||
return res
|
||||
|
||||
proc genLegalRookMoves(game: Game, field: int, color: Color): seq[Move] =
|
||||
## Generates all legal rook moves starting from `field` in a `game` for a `color`.
|
||||
## Generates all legal rook moves in a `game` starting from `field` for a
|
||||
## `color`.
|
||||
if game.board[field] != WRook * ord(color):
|
||||
return @[]
|
||||
var res = newSeq[Move]()
|
||||
@ -602,7 +636,8 @@ proc genLegalRookMoves(game: Game, field: int, color: Color): seq[Move] =
|
||||
return res
|
||||
|
||||
proc genLegalQueenMoves(game: Game, field: int, color: Color): seq[Move] =
|
||||
## Generates all legal queen moves starting from `field` in a `game` for a `color`.
|
||||
## Generates all legal queen moves in a `game` starting from `field` for a
|
||||
## `color`.
|
||||
if game.board[field] != WQueen * ord(color):
|
||||
return @[]
|
||||
var res = newSeq[Move]()
|
||||
@ -613,7 +648,8 @@ proc genLegalQueenMoves(game: Game, field: int, color: Color): seq[Move] =
|
||||
return res
|
||||
|
||||
proc genLegalKingMoves(game: Game, field: int, color: Color): seq[Move] =
|
||||
## Generates all legal king moves starting from `field` in a `game` for a `color`.
|
||||
## Generates all legal king moves in a `game` starting from `field` for a
|
||||
## `color`.
|
||||
if game.board[field] != WKing * ord(color):
|
||||
return @[]
|
||||
var res = newSeq[Move]()
|
||||
@ -638,7 +674,8 @@ proc genPawnPromotion(move: Move, color: Color): seq[Move] =
|
||||
return promotions
|
||||
|
||||
proc genLegalPawnMoves(game: Game, field: int, color: Color): seq[Move] =
|
||||
## Generates all legal pawn moves starting from `field` in a `game` for a `color`.
|
||||
## Generates all legal pawn moves in a `game` starting from `field` for a
|
||||
## `color`.
|
||||
if game.board[field] != WPawn * ord(color):
|
||||
return @[]
|
||||
var res = newSeq[Move]()
|
||||
@ -653,7 +690,7 @@ proc genLegalPawnMoves(game: Game, field: int, color: Color): seq[Move] =
|
||||
return res
|
||||
|
||||
proc genLegalMoves*(game: Game, field: int, color: Color): seq[Move] =
|
||||
## Generates all legal moves starting from `field` in a `game` for a `color`.
|
||||
## Generates all legal moves in a `game` starting from `field` for a `color`.
|
||||
var legal_moves = newSeq[Move]()
|
||||
var target = ord(color) * game.board[field]
|
||||
if 0 < target and target < WEnPassant:
|
||||
@ -683,9 +720,11 @@ proc genLegalMoves*(game: Game, color: Color): seq[Move] =
|
||||
|
||||
proc castling(game: var Game, kstart: int, dest_kingside: bool,
|
||||
color: Color): bool {.discardable.} =
|
||||
## Tries to castle in a given `game` with the king of a given `color` from `start`.
|
||||
## Tries to castle in a given `game` with the king of a given `color` from
|
||||
## `kstart`.
|
||||
## `dest_kingside` for kingside castling, else castling is queenside.
|
||||
## This process checks for the legality of the move and performs the switch of `game.to_move`
|
||||
## This process checks for the legality of the move and performs the switch
|
||||
## of `game.to_move`
|
||||
if game.toMove != color:
|
||||
return false
|
||||
var kdest = kstart
|
||||
@ -717,12 +756,10 @@ proc castling(game: var Game, kstart: int, dest_kingside: bool,
|
||||
return true
|
||||
return false
|
||||
|
||||
proc getPrevBoard*(game: Game): seq[Board] =
|
||||
return game.previousBoard
|
||||
|
||||
proc checkedMove*(game: var Game, move: Move): bool {.discardable.} =
|
||||
## Tries to make a move in a given `game` with the piece of a given `color` from `start` to `dest`.
|
||||
## This process checks for the legality of the move and performs the switch of `game.to_move`
|
||||
## Tries to make a `move` in a given `game``.
|
||||
## This process checks for the legality of the move and performs the switch
|
||||
## of `game.to_move` with exception of castling (castling() switches).
|
||||
let start = move.start
|
||||
let dest = move.dest
|
||||
let color = move.color
|
||||
@ -769,15 +806,16 @@ proc checkedMove*(game: var Game, move: Move): bool {.discardable.} =
|
||||
return true
|
||||
|
||||
proc hasNoMoves(game: Game, color: Color): bool =
|
||||
## Checks if a player of a given `color` has no legal moves in a `game`.
|
||||
## Returns true if the `color` player has no legal moves in a `game`.
|
||||
return (game.genLegalMoves(color) == @[])
|
||||
|
||||
proc isCheckmate*(game: Game, color: Color): bool =
|
||||
## Checks if a player of a given `color` in a `game` is checkmate.
|
||||
## Returns true if the `color` player is checkmate in a `game`.
|
||||
return game.hasNoMoves(color) and game.isInCheck(color)
|
||||
|
||||
proc threeMoveRep(game: Game): bool =
|
||||
## Checks if a `rep`-times repitition happened on the last move of the `game`.
|
||||
## Returns true if a 3-fold repitition happened on the last move of the
|
||||
## `game`.
|
||||
var lastState = game.previousBoard[game.previousBoard.high]
|
||||
var lastCastleRights = game.previousCastleRights[game.previousBoard.high]
|
||||
var reps = 0
|
||||
@ -788,14 +826,14 @@ proc threeMoveRep(game: Game): bool =
|
||||
return reps >= 3
|
||||
|
||||
proc fiftyMoveRule(game: Game): bool =
|
||||
## Checks if a draw with the fifty move rule is available in a `game`.
|
||||
## Returns true if a draw can be claimed by the 50 move rule in a `game`.
|
||||
return game.fiftyMoveCounter >= 100
|
||||
|
||||
proc isDrawClaimable*(game: Game): bool =
|
||||
## Checks if a draw is claimable by either player.
|
||||
## Returns true if a draw is claimable by either player.
|
||||
return game.threeMoveRep() or game.fiftyMoveRule()
|
||||
|
||||
proc isStalemate*(game: Game, color: Color): bool =
|
||||
## Checks if a player of a given `color` in a `game` is stalemate.
|
||||
## Returns true if the `color` player is stalemate in a `game`.
|
||||
return (game.hasNoMoves(color) and not game.isInCheck(color)) or
|
||||
game.board.checkInsufficientMaterial()
|
||||
|
||||
Loading…
x
Reference in New Issue
Block a user