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test.py
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#!/usr/bin/env python
# -*- coding: utf-8 -*-
#
# This file is part of the python-chess library.
# Copyright (C) 2012-2017 Niklas Fiekas <[email protected]>
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program. If not, see <http://www.gnu.org/licenses/>.
import chess
import chess.polyglot
import chess.pgn
import chess.uci
import chess.xboard
import chess.syzygy
import chess.gaviota
import chess.variant
import collections
import copy
import os
import os.path
import textwrap
import sys
import time
import threading
import logging
import platform
import unittest
try:
from StringIO import StringIO # Python 2
except ImportError:
from io import StringIO # Python 3
class RaiseLogHandler(logging.StreamHandler):
def handle(self, record):
super(RaiseLogHandler, self).handle(record)
raise RuntimeError("was expecting no log messages")
def catchAndSkip(signature, message=None):
def _decorator(f):
def _wrapper(self):
try:
return f(self)
except signature as err:
raise unittest.SkipTest(message or err)
return _wrapper
return _decorator
class SquareTestCase(unittest.TestCase):
def test_square(self):
for square in chess.SQUARES:
file_index = chess.square_file(square)
rank_index = chess.square_rank(square)
self.assertEqual(chess.square(file_index, rank_index), square, chess.SQUARE_NAMES[square])
def test_shifts(self):
shifts = [
chess.shift_down,
chess.shift_2_down,
chess.shift_up,
chess.shift_2_up,
chess.shift_right,
chess.shift_2_right,
chess.shift_left,
chess.shift_2_left,
chess.shift_up_left,
chess.shift_up_right,
chess.shift_down_left,
chess.shift_down_right,
]
for shift in shifts:
for bb_square in chess.BB_SQUARES:
shifted = shift(bb_square)
c = chess.popcount(shifted)
self.assertLessEqual(c, 1)
self.assertEqual(c, chess.popcount(shifted & chess.BB_ALL))
class MoveTestCase(unittest.TestCase):
def test_equality(self):
a = chess.Move(chess.A1, chess.A2)
b = chess.Move(chess.A1, chess.A2)
c = chess.Move(chess.H7, chess.H8, chess.BISHOP)
d1 = chess.Move(chess.H7, chess.H8)
d2 = chess.Move(chess.H7, chess.H8)
self.assertEqual(a, b)
self.assertEqual(b, a)
self.assertEqual(d1, d2)
self.assertNotEqual(a, c)
self.assertNotEqual(c, d1)
self.assertNotEqual(b, d1)
self.assertFalse(d1 != d2)
def test_uci_parsing(self):
self.assertEqual(chess.Move.from_uci("b5c7").uci(), "b5c7")
self.assertEqual(chess.Move.from_uci("e7e8q").uci(), "e7e8q")
self.assertEqual(chess.Move.from_uci("P@e4").uci(), "P@e4")
self.assertEqual(chess.Move.from_uci("B@f4").uci(), "B@f4")
def test_invalid_uci(self):
with self.assertRaises(ValueError):
chess.Move.from_uci("")
with self.assertRaises(ValueError):
chess.Move.from_uci("N")
with self.assertRaises(ValueError):
chess.Move.from_uci("z1g3")
with self.assertRaises(ValueError):
chess.Move.from_uci("Q@g9")
def test_copy(self):
a = chess.Move.from_uci("N@f3")
b = chess.Move.from_uci("a1h8")
c = chess.Move.from_uci("g7g8r")
self.assertEqual(copy.copy(a), a)
self.assertEqual(copy.copy(b), b)
self.assertEqual(copy.copy(c), c)
class PieceTestCase(unittest.TestCase):
def test_equality(self):
a = chess.Piece(chess.BISHOP, chess.WHITE)
b = chess.Piece(chess.KING, chess.BLACK)
c = chess.Piece(chess.KING, chess.WHITE)
d1 = chess.Piece(chess.BISHOP, chess.WHITE)
d2 = chess.Piece(chess.BISHOP, chess.WHITE)
self.assertEqual(a, d1)
self.assertEqual(d1, a)
self.assertEqual(d1, d2)
self.assertEqual(repr(a), repr(d1))
self.assertNotEqual(a, b)
self.assertNotEqual(b, c)
self.assertNotEqual(b, d1)
self.assertNotEqual(a, c)
self.assertFalse(d1 != d2)
self.assertNotEqual(repr(a), repr(b))
self.assertNotEqual(repr(b), repr(c))
self.assertNotEqual(repr(b), repr(d1))
self.assertNotEqual(repr(a), repr(c))
def test_from_symbol(self):
white_knight = chess.Piece.from_symbol("N")
self.assertEqual(white_knight.color, chess.WHITE)
self.assertEqual(white_knight.piece_type, chess.KNIGHT)
self.assertEqual(white_knight.symbol(), "N")
black_queen = chess.Piece.from_symbol("q")
self.assertEqual(black_queen.color, chess.BLACK)
self.assertEqual(black_queen.piece_type, chess.QUEEN)
self.assertEqual(black_queen.symbol(), "q")
class BoardTestCase(unittest.TestCase):
def test_default_position(self):
board = chess.Board()
self.assertEqual(board.piece_at(chess.B1), chess.Piece.from_symbol("N"))
self.assertEqual(board.fen(), chess.STARTING_FEN)
self.assertEqual(board.turn, chess.WHITE)
def test_empty(self):
board = chess.Board.empty()
self.assertEqual(board.fen(), "8/8/8/8/8/8/8/8 w - - 0 1")
self.assertEqual(board, chess.Board(None))
def test_from_epd(self):
base_epd = "rnbqkb1r/ppp1pppp/5n2/3P4/8/8/PPPP1PPP/RNBQKBNR w KQkq -"
board, ops = chess.Board.from_epd(base_epd + " ce 55;")
self.assertEqual(ops["ce"], 55)
self.assertEqual(board.fen(), base_epd + " 0 1")
def test_move_making(self):
board = chess.Board()
move = chess.Move(chess.E2, chess.E4)
board.push(move)
self.assertEqual(board.peek(), move)
def test_fen(self):
board = chess.Board()
self.assertEqual(board.fen(), chess.STARTING_FEN)
fen = "6k1/pb3pp1/1p2p2p/1Bn1P3/8/5N2/PP1q1PPP/6K1 w - - 0 24"
board.set_fen(fen)
self.assertEqual(board.fen(), fen)
board.push(chess.Move.from_uci("f3d2"))
self.assertEqual(board.fen(), "6k1/pb3pp1/1p2p2p/1Bn1P3/8/8/PP1N1PPP/6K1 b - - 0 24")
def test_xfen(self):
# https://de.wikipedia.org/wiki/Forsyth-Edwards-Notation#Beispiel
xfen = "rn2k1r1/ppp1pp1p/3p2p1/5bn1/P7/2N2B2/1PPPPP2/2BNK1RR w Gkq - 4 11"
board = chess.Board(xfen, chess960=True)
self.assertEqual(board.castling_rights, chess.BB_G1 | chess.BB_A8 | chess.BB_G8)
self.assertEqual(board.clean_castling_rights(), chess.BB_G1 | chess.BB_A8 | chess.BB_G8)
self.assertEqual(board.shredder_fen(), "rn2k1r1/ppp1pp1p/3p2p1/5bn1/P7/2N2B2/1PPPPP2/2BNK1RR w Gga - 4 11")
self.assertEqual(board.fen(), xfen)
self.assertTrue(board.has_castling_rights(chess.WHITE))
self.assertTrue(board.has_castling_rights(chess.BLACK))
self.assertTrue(board.has_kingside_castling_rights(chess.BLACK))
self.assertTrue(board.has_kingside_castling_rights(chess.WHITE))
self.assertTrue(board.has_queenside_castling_rights(chess.BLACK))
self.assertFalse(board.has_queenside_castling_rights(chess.WHITE))
# Chess960 position #284.
board = chess.Board("rkbqrbnn/pppppppp/8/8/8/8/PPPPPPPP/RKBQRBNN w - - 0 1", chess960=True)
board.castling_rights = board.rooks
self.assertTrue(board.clean_castling_rights() & chess.BB_A1)
self.assertEqual(board.fen(), "rkbqrbnn/pppppppp/8/8/8/8/PPPPPPPP/RKBQRBNN w KQkq - 0 1")
self.assertEqual(board.shredder_fen(), "rkbqrbnn/pppppppp/8/8/8/8/PPPPPPPP/RKBQRBNN w EAea - 0 1")
# Valid en passant square on illegal board.
fen = "8/8/8/pP6/8/8/8/8 w - a6 0 1"
board = chess.Board(fen)
self.assertEqual(board.fen(), fen)
# Illegal en passant square in illegal board.
fen = "1r6/8/8/pP6/8/8/8/1K6 w - a6 0 1"
board = chess.Board(fen)
self.assertEqual(board.fen(), "1r6/8/8/pP6/8/8/8/1K6 w - - 0 1")
def test_fen_en_passant(self):
board = chess.Board()
board.push_san("e4")
self.assertEqual(board.fen(en_passant="fen"), "rnbqkbnr/pppppppp/8/8/4P3/8/PPPP1PPP/RNBQKBNR b KQkq e3 0 1")
self.assertEqual(board.fen(en_passant="xfen"), "rnbqkbnr/pppppppp/8/8/4P3/8/PPPP1PPP/RNBQKBNR b KQkq - 0 1")
def test_get_set(self):
board = chess.Board()
self.assertEqual(board.piece_at(chess.B1), chess.Piece.from_symbol("N"))
board.remove_piece_at(chess.E2)
self.assertEqual(board.piece_at(chess.E2), None)
board.set_piece_at(chess.E4, chess.Piece.from_symbol("r"))
self.assertEqual(board.piece_type_at(chess.E4), chess.ROOK)
board.set_piece_at(chess.F1, None)
self.assertEqual(board.piece_at(chess.F1), None)
board.set_piece_at(chess.H7, chess.Piece.from_symbol("Q"), promoted=True)
self.assertEqual(board.promoted, chess.BB_H7)
def test_pawn_captures(self):
board = chess.Board()
# Kings gambit.
board.push(chess.Move.from_uci("e2e4"))
board.push(chess.Move.from_uci("e7e5"))
board.push(chess.Move.from_uci("f2f4"))
# Accepted.
exf4 = chess.Move.from_uci("e5f4")
self.assertIn(exf4, board.pseudo_legal_moves)
self.assertIn(exf4, board.legal_moves)
board.push(exf4)
board.pop()
def test_pawn_move_generation(self):
board = chess.Board("8/2R1P3/8/2pp4/2k1r3/P7/8/1K6 w - - 1 55")
self.assertEqual(len(list(board.generate_pseudo_legal_moves())), 16)
def test_single_step_pawn_move(self):
board = chess.Board()
a3 = chess.Move.from_uci("a2a3")
self.assertIn(a3, board.pseudo_legal_moves)
self.assertIn(a3, board.legal_moves)
board.push(a3)
board.pop()
self.assertEqual(board.fen(), chess.STARTING_FEN)
def test_castling(self):
board = chess.Board("r3k2r/8/8/8/8/8/8/R3K2R w KQkq - 1 1")
# Let white castle short.
move = board.parse_san("O-O")
self.assertEqual(move, chess.Move.from_uci("e1g1"))
self.assertEqual(board.san(move), "O-O")
self.assertIn(move, board.legal_moves)
board.push(move)
# Let black castle long.
move = board.parse_san("O-O-O")
self.assertEqual(board.san(move), "O-O-O")
self.assertIn(move, board.legal_moves)
board.push(move)
self.assertEqual(board.fen(), "2kr3r/8/8/8/8/8/8/R4RK1 w - - 3 2")
# Undo both castling moves.
board.pop()
board.pop()
self.assertEqual(board.fen(), "r3k2r/8/8/8/8/8/8/R3K2R w KQkq - 1 1")
# Let white castle long.
move = board.parse_san("O-O-O")
self.assertEqual(board.san(move), "O-O-O")
self.assertIn(move, board.legal_moves)
board.push(move)
# Let black castle short.
move = board.parse_san("O-O")
self.assertEqual(board.san(move), "O-O")
self.assertIn(move, board.legal_moves)
board.push(move)
self.assertEqual(board.fen(), "r4rk1/8/8/8/8/8/8/2KR3R w - - 3 2")
# Undo both castling moves.
board.pop()
board.pop()
self.assertEqual(board.fen(), "r3k2r/8/8/8/8/8/8/R3K2R w KQkq - 1 1")
def test_ninesixty_castling(self):
fen = "3r1k1r/4pp2/8/8/8/8/8/4RKR1 w Gd - 1 1"
board = chess.Board(fen, chess960=True)
# Let white do the king side swap.
move = board.parse_san("O-O")
self.assertEqual(board.san(move), "O-O")
self.assertEqual(move.from_square, chess.F1)
self.assertEqual(move.to_square, chess.G1)
self.assertIn(move, board.legal_moves)
board.push(move)
self.assertEqual(board.shredder_fen(), "3r1k1r/4pp2/8/8/8/8/8/4RRK1 b d - 2 1")
# Black can not castle kingside.
self.assertNotIn(chess.Move.from_uci("e8h8"), board.legal_moves)
# Let black castle queenside.
move = board.parse_san("O-O-O")
self.assertEqual(board.san(move), "O-O-O")
self.assertEqual(move.from_square, chess.F8)
self.assertEqual(move.to_square, chess.D8)
self.assertIn(move, board.legal_moves)
board.push(move)
self.assertEqual(board.shredder_fen(), "2kr3r/4pp2/8/8/8/8/8/4RRK1 w - - 3 2")
# Restore initial position.
board.pop()
board.pop()
self.assertEqual(board.shredder_fen(), fen)
fen = "Qr4k1/4pppp/8/8/8/8/8/R5KR w Hb - 0 1"
board = chess.Board(fen, chess960=True)
# White can just hop the rook over.
move = board.parse_san("O-O")
self.assertEqual(board.san(move), "O-O")
self.assertEqual(move.from_square, chess.G1)
self.assertEqual(move.to_square, chess.H1)
self.assertIn(move, board.legal_moves)
board.push(move)
self.assertEqual(board.shredder_fen(), "Qr4k1/4pppp/8/8/8/8/8/R4RK1 b b - 1 1")
# Black can not castle queenside nor kingside.
self.assertFalse(any(board.generate_castling_moves()))
# Restore initial position.
board.pop()
self.assertEqual(board.shredder_fen(), fen)
def test_selective_castling(self):
board = chess.Board("r3k2r/pppppppp/8/8/8/8/PPPPPPPP/R3K2R w KQkq - 0 1")
# King not selected
self.assertFalse(any(board.generate_castling_moves(chess.BB_ALL & ~board.kings)))
# Rook on h1 not selected
moves = board.generate_castling_moves(chess.BB_ALL, chess.BB_ALL & ~chess.BB_H1)
self.assertEqual(len(list(moves)), 1)
def test_castling_right_not_destroyed_bug(self):
# A rook move from H8 to H1 was only taking whites possible castling
# rights away.
board = chess.Board("2r1k2r/2qbbpp1/p2pp3/1p3PP1/Pn2P3/1PN1B3/1P3QB1/1K1R3R b k - 0 22")
board.push_san("Rxh1")
self.assertEqual(board.epd(), "2r1k3/2qbbpp1/p2pp3/1p3PP1/Pn2P3/1PN1B3/1P3QB1/1K1R3r w - -")
def test_invalid_castling_rights(self):
# KQkq is not valid in this standard chess position.
board = chess.Board("1r2k3/8/8/8/8/8/8/R3KR2 w KQkq - 0 1")
self.assertEqual(board.status(), chess.STATUS_BAD_CASTLING_RIGHTS)
self.assertEqual(board.fen(), "1r2k3/8/8/8/8/8/8/R3KR2 w Q - 0 1")
self.assertTrue(board.has_queenside_castling_rights(chess.WHITE))
self.assertFalse(board.has_kingside_castling_rights(chess.WHITE))
self.assertFalse(board.has_queenside_castling_rights(chess.BLACK))
self.assertFalse(board.has_kingside_castling_rights(chess.BLACK))
board = chess.Board("4k2r/8/8/8/8/8/8/R1K5 w KQkq - 0 1", chess960=True)
self.assertEqual(board.status(), chess.STATUS_BAD_CASTLING_RIGHTS)
self.assertEqual(board.fen(), "4k2r/8/8/8/8/8/8/R1K5 w Qk - 0 1")
board = chess.Board("1r2k3/8/1p6/8/8/5P2/8/1R2KR2 w KQkq - 0 1", chess960=True)
self.assertEqual(board.status(), chess.STATUS_BAD_CASTLING_RIGHTS)
self.assertEqual(board.fen(), "1r2k3/8/1p6/8/8/5P2/8/1R2KR2 w KQq - 0 1")
def test_ninesixty_different_king_and_rook_file(self):
# Theoretically this position (with castling rights) can not be reached
# with a series of legal moves from one of the 960 starting positions.
# Decision: We don't care. Neither does Stockfish or lichess.org.
fen = "1r1k1r2/5p2/8/8/8/8/3N4/R5KR b KQkq - 0 1"
board = chess.Board(fen, chess960=True)
self.assertEqual(board.fen(), fen)
def test_ninesixty_prevented_castle(self):
board = chess.Board("4k3/8/8/1b6/8/8/8/5RKR w KQ - 0 1", chess960=True)
self.assertFalse(board.is_legal(chess.Move.from_uci("g1f1")))
def test_insufficient_material(self):
# Starting position.
board = chess.Board()
self.assertFalse(board.is_insufficient_material())
# King vs. King + 2 bishops of the same color.
board = chess.Board("k1K1B1B1/8/8/8/8/8/8/8 w - - 7 32")
self.assertTrue(board.is_insufficient_material())
# Add bishop of opposite color for the weaker side.
board.set_piece_at(chess.B8, chess.Piece.from_symbol("b"))
self.assertFalse(board.is_insufficient_material())
def test_promotion_with_check(self):
board = chess.Board("8/6P1/2p5/1Pqk4/6P1/2P1RKP1/4P1P1/8 w - - 0 1")
board.push(chess.Move.from_uci("g7g8q"))
self.assertTrue(board.is_check())
self.assertEqual(board.fen(), "6Q1/8/2p5/1Pqk4/6P1/2P1RKP1/4P1P1/8 b - - 0 1")
board = chess.Board("8/8/8/3R1P2/8/2k2K2/3p4/r7 b - - 0 82")
board.push_san("d1=Q+")
self.assertEqual(board.fen(), "8/8/8/3R1P2/8/2k2K2/8/r2q4 w - - 0 83")
def test_scholars_mate(self):
board = chess.Board()
e4 = chess.Move.from_uci("e2e4")
self.assertIn(e4, board.legal_moves)
board.push(e4)
e5 = chess.Move.from_uci("e7e5")
self.assertIn(e5, board.legal_moves)
board.push(e5)
Qf3 = chess.Move.from_uci("d1f3")
self.assertIn(Qf3, board.legal_moves)
board.push(Qf3)
Nc6 = chess.Move.from_uci("b8c6")
self.assertIn(Nc6, board.legal_moves)
board.push(Nc6)
Bc4 = chess.Move.from_uci("f1c4")
self.assertIn(Bc4, board.legal_moves)
board.push(Bc4)
Rb8 = chess.Move.from_uci("a8b8")
self.assertIn(Rb8, board.legal_moves)
board.push(Rb8)
self.assertFalse(board.is_check())
self.assertFalse(board.is_checkmate())
self.assertFalse(board.is_game_over())
self.assertFalse(board.is_stalemate())
Qf7_mate = chess.Move.from_uci("f3f7")
self.assertIn(Qf7_mate, board.legal_moves)
board.push(Qf7_mate)
self.assertTrue(board.is_check())
self.assertTrue(board.is_checkmate())
self.assertTrue(board.is_game_over())
self.assertTrue(board.is_game_over(claim_draw=True))
self.assertFalse(board.is_stalemate())
self.assertEqual(board.fen(), "1rbqkbnr/pppp1Qpp/2n5/4p3/2B1P3/8/PPPP1PPP/RNB1K1NR b KQk - 0 4")
def test_result(self):
# Undetermined.
board = chess.Board()
self.assertEqual(board.result(claim_draw=True), "*")
# White checkmated.
board = chess.Board("rnb1kbnr/pppp1ppp/8/4p3/6Pq/5P2/PPPPP2P/RNBQKBNR w KQkq - 1 3")
self.assertEqual(board.result(claim_draw=True), "0-1")
# Stalemate.
board = chess.Board("7K/7P/7k/8/6q1/8/8/8 w - - 0 1")
self.assertEqual(board.result(), "1/2-1/2")
# Insufficient material.
board = chess.Board("4k3/8/8/8/8/5B2/8/4K3 w - - 0 1")
self.assertEqual(board.result(), "1/2-1/2")
# Fiftyseven-move rule.
board = chess.Board("4k3/8/6r1/8/8/8/2R5/4K3 w - - 369 1")
self.assertEqual(board.result(), "1/2-1/2")
# Fifty-move rule.
board = chess.Board("4k3/8/6r1/8/8/8/2R5/4K3 w - - 120 1")
self.assertEqual(board.result(), "*")
self.assertEqual(board.result(claim_draw=True), "1/2-1/2")
def test_san(self):
# Castling with check.
fen = "rnbk1b1r/ppp2pp1/5n1p/4p1B1/2P5/2N5/PP2PPPP/R3KBNR w KQ - 0 7"
board = chess.Board(fen)
long_castle_check = chess.Move.from_uci("e1a1")
self.assertEqual(board.san(long_castle_check), "O-O-O+")
self.assertEqual(board.fen(), fen)
# En passant mate.
fen = "6bk/7b/8/3pP3/8/8/8/Q3K3 w - d6 0 2"
board = chess.Board(fen)
fxe6_mate_ep = chess.Move.from_uci("e5d6")
self.assertEqual(board.san(fxe6_mate_ep), "exd6#")
self.assertEqual(board.fen(), fen)
# Test ambiguation.
fen = "N3k2N/8/8/3N4/N4N1N/2R5/1R6/4K3 w - - 0 1"
board = chess.Board(fen)
self.assertEqual(board.san(chess.Move.from_uci("e1f1")), "Kf1")
self.assertEqual(board.san(chess.Move.from_uci("c3c2")), "Rcc2")
self.assertEqual(board.san(chess.Move.from_uci("b2c2")), "Rbc2")
self.assertEqual(board.san(chess.Move.from_uci("a4b6")), "N4b6")
self.assertEqual(board.san(chess.Move.from_uci("h8g6")), "N8g6")
self.assertEqual(board.san(chess.Move.from_uci("h4g6")), "Nh4g6")
self.assertEqual(board.fen(), fen)
# Do not disambiguate illegal alternatives.
fen = "8/8/8/R2nkn2/8/8/2K5/8 b - - 0 1"
board = chess.Board(fen)
self.assertEqual(board.san(chess.Move.from_uci("f5e3")), "Ne3+")
self.assertEqual(board.fen(), fen)
# Promotion.
fen = "7k/1p2Npbp/8/2P5/1P1r4/3b2QP/3q1pPK/2RB4 b - - 1 29"
board = chess.Board(fen)
self.assertEqual(board.san(chess.Move.from_uci("f2f1q")), "f1=Q")
self.assertEqual(board.san(chess.Move.from_uci("f2f1n")), "f1=N+")
self.assertEqual(board.fen(), fen)
def test_san_newline(self):
fen = "rnbqk2r/ppppppbp/5np1/8/8/5NP1/PPPPPPBP/RNBQK2R w KQkq - 2 4"
board = chess.Board(fen)
with self.assertRaises(ValueError):
board.parse_san("O-O\n")
with self.assertRaises(ValueError):
board.parse_san("Nc3\n")
def test_variation_san(self):
board = chess.Board()
self.assertEqual('1. e4 e5 2. Nf3',
board.variation_san([chess.Move.from_uci(m) for m in
['e2e4', 'e7e5', 'g1f3']]))
self.assertEqual('1. e4 e5 2. Nf3 Nc6 3. Bb5 a6',
board.variation_san([chess.Move.from_uci(m) for m in
['e2e4', 'e7e5', 'g1f3', 'b8c6', 'f1b5', 'a7a6']]))
fen = "rn1qr1k1/1p2bppp/p3p3/3pP3/P2P1B2/2RB1Q1P/1P3PP1/R5K1 w - - 0 19"
board = chess.Board(fen)
variation = ['d3h7', 'g8h7', 'f3h5', 'h7g8', 'c3g3', 'e7f8', 'f4g5',
'e8e7', 'g5f6', 'b8d7', 'h5h6', 'd7f6', 'e5f6', 'g7g6',
'f6e7', 'f8e7']
var_w = board.variation_san([chess.Move.from_uci(m) for m in variation])
self.assertEqual(("19. Bxh7+ Kxh7 20. Qh5+ Kg8 21. Rg3 Bf8 22. Bg5 Re7 "
"23. Bf6 Nd7 24. Qh6 Nxf6 25. exf6 g6 26. fxe7 Bxe7"),
var_w)
self.assertEqual(fen, board.fen(), msg="Board unchanged by variation_san")
board.push(chess.Move.from_uci(variation.pop(0)))
var_b = board.variation_san([chess.Move.from_uci(m) for m in variation])
self.assertEqual(("19...Kxh7 20. Qh5+ Kg8 21. Rg3 Bf8 22. Bg5 Re7 "
"23. Bf6 Nd7 24. Qh6 Nxf6 25. exf6 g6 26. fxe7 Bxe7"),
var_b)
illegal_variation = ['d3h7', 'g8h7', 'f3h6', 'h7g8']
board = chess.Board(fen)
with self.assertRaises(ValueError) as err:
board.variation_san([chess.Move.from_uci(m) for m in illegal_variation])
message = str(err.exception)
self.assertIn('illegal move', message.lower(),
msg="Error [{0}] mentions illegal move".format(message))
self.assertIn('f3h6', message,
msg="Illegal move f3h6 appears in message [{0}]".format(message))
def test_move_stack_usage(self):
board = chess.Board()
board.push_uci("d2d4")
board.push_uci("d7d5")
board.push_uci("g1f3")
board.push_uci("c8f5")
board.push_uci("e2e3")
board.push_uci("e7e6")
board.push_uci("f1d3")
board.push_uci("f8d6")
board.push_uci("e1h1")
san = chess.Board().variation_san(board.move_stack)
self.assertEqual(san, "1. d4 d5 2. Nf3 Bf5 3. e3 e6 4. Bd3 Bd6 5. O-O")
def test_is_legal_move(self):
fen = "3k4/6P1/7P/8/K7/8/8/4R3 w - - 0 1"
board = chess.Board(fen)
# Legal moves: Rg1, g8=R+.
self.assertIn(chess.Move.from_uci("e1g1"), board.legal_moves)
self.assertIn(chess.Move.from_uci("g7g8r"), board.legal_moves)
# Impossible promotion: Kb5, h7.
self.assertNotIn(chess.Move.from_uci("a5b5q"), board.legal_moves)
self.assertNotIn(chess.Move.from_uci("h6h7n"), board.legal_moves)
# Missing promotion.
self.assertNotIn(chess.Move.from_uci("g7g8"), board.legal_moves)
self.assertEqual(board.fen(), fen)
def test_move_count(self):
board = chess.Board("1N2k3/P7/8/8/3n4/8/2PP4/R3K2R w KQ - 0 1")
self.assertEqual(board.pseudo_legal_moves.count(), 8 + 4 + 3 + 2 + 1 + 6 + 9)
def test_polyglot(self):
# Test polyglot compability using test data from
# http://hardy.uhasselt.be/Toga/book_format.html. Forfeiting castling
# rights should not reset the half-move counter, though.
board = chess.Board()
self.assertEqual(board.fen(), "rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1")
self.assertEqual(chess.polyglot.zobrist_hash(board), 0x463b96181691fc9c)
board.push_san("e4")
self.assertEqual(board.fen(), "rnbqkbnr/pppppppp/8/8/4P3/8/PPPP1PPP/RNBQKBNR b KQkq - 0 1")
self.assertEqual(chess.polyglot.zobrist_hash(board), 0x823c9b50fd114196)
board.push_san("d5")
self.assertEqual(board.fen(), "rnbqkbnr/ppp1pppp/8/3p4/4P3/8/PPPP1PPP/RNBQKBNR w KQkq - 0 2")
self.assertEqual(chess.polyglot.zobrist_hash(board), 0x0756b94461c50fb0)
board.push_san("e5")
self.assertEqual(board.fen(), "rnbqkbnr/ppp1pppp/8/3pP3/8/8/PPPP1PPP/RNBQKBNR b KQkq - 0 2")
self.assertEqual(chess.polyglot.zobrist_hash(board), 0x662fafb965db29d4)
board.push_san("f5")
self.assertEqual(board.fen(), "rnbqkbnr/ppp1p1pp/8/3pPp2/8/8/PPPP1PPP/RNBQKBNR w KQkq f6 0 3")
self.assertEqual(chess.polyglot.zobrist_hash(board), 0x22a48b5a8e47ff78)
board.push_san("Ke2")
self.assertEqual(board.fen(), "rnbqkbnr/ppp1p1pp/8/3pPp2/8/8/PPPPKPPP/RNBQ1BNR b kq - 1 3")
self.assertEqual(chess.polyglot.zobrist_hash(board), 0x652a607ca3f242c1)
board.push_san("Kf7")
self.assertEqual(board.fen(), "rnbq1bnr/ppp1pkpp/8/3pPp2/8/8/PPPPKPPP/RNBQ1BNR w - - 2 4")
self.assertEqual(chess.polyglot.zobrist_hash(board), 0x00fdd303c946bdd9)
board = chess.Board()
board.push_san("a4")
board.push_san("b5")
board.push_san("h4")
board.push_san("b4")
board.push_san("c4")
self.assertEqual(board.fen(), "rnbqkbnr/p1pppppp/8/8/PpP4P/8/1P1PPPP1/RNBQKBNR b KQkq c3 0 3")
self.assertEqual(chess.polyglot.zobrist_hash(board), 0x3c8123ea7b067637)
board.push_san("bxc3")
board.push_san("Ra3")
self.assertEqual(board.fen(), "rnbqkbnr/p1pppppp/8/8/P6P/R1p5/1P1PPPP1/1NBQKBNR b Kkq - 1 4")
self.assertEqual(chess.polyglot.zobrist_hash(board), 0x5c3f9b829b279560)
def test_castling_move_generation_bug(self):
# Specific test position right after castling.
fen = "rnbqkbnr/2pp1ppp/8/4p3/2BPP3/P1N2N2/PB3PPP/2RQ1RK1 b kq - 1 10"
board = chess.Board(fen)
illegal_move = chess.Move.from_uci("g1g2")
self.assertNotIn(illegal_move, board.legal_moves)
self.assertNotIn(illegal_move, list(board.legal_moves))
self.assertNotIn(illegal_move, board.pseudo_legal_moves)
self.assertNotIn(illegal_move, list(board.pseudo_legal_moves))
# Make a move.
board.push_san("exd4")
# Already castled short, can not castle long.
illegal_move = chess.Move.from_uci("e1c1")
self.assertNotIn(illegal_move, board.pseudo_legal_moves)
self.assertNotIn(illegal_move, board.generate_pseudo_legal_moves())
self.assertNotIn(illegal_move, board.legal_moves)
self.assertNotIn(illegal_move, list(board.legal_moves))
# Unmake the move.
board.pop()
# Generate all pseudo legal moves, two moves deep.
for move in board.pseudo_legal_moves:
board.push(move)
for move in board.pseudo_legal_moves:
board.push(move)
board.pop()
board.pop()
# Check that board is still consistent.
self.assertEqual(board.fen(), fen)
self.assertTrue(board.kings & chess.BB_G1)
self.assertTrue(board.occupied & chess.BB_G1)
self.assertTrue(board.occupied_co[chess.WHITE] & chess.BB_G1)
self.assertEqual(board.piece_at(chess.G1), chess.Piece(chess.KING, chess.WHITE))
self.assertEqual(board.piece_at(chess.C1), chess.Piece(chess.ROOK, chess.WHITE))
def test_move_generation_bug(self):
# Specific problematic position.
fen = "4kb1r/3b1ppp/8/1r2pNB1/6P1/pP2QP2/P6P/4R1K1 w k - 0 27"
board = chess.Board(fen)
# Make a move.
board.push_san("Re2")
# Check for the illegal move.
illegal_move = chess.Move.from_uci("e8f8")
self.assertNotIn(illegal_move, board.pseudo_legal_moves)
self.assertNotIn(illegal_move, board.generate_pseudo_legal_moves())
self.assertNotIn(illegal_move, board.legal_moves)
self.assertNotIn(illegal_move, board.generate_legal_moves())
# Generate all pseudo legal moves.
for a in board.pseudo_legal_moves:
board.push(a)
board.pop()
# Unmake the move.
board.pop()
# Check that board is still consistent.
self.assertEqual(board.fen(), fen)
def test_stateful_move_generation_bug(self):
board = chess.Board("r1b1k3/p2p1Nr1/n2b3p/3pp1pP/2BB1p2/P3P2R/Q1P3P1/R3K1N1 b Qq - 0 1")
count = 0
for move in board.legal_moves:
board.push(move)
list(board.generate_legal_moves())
count += 1
board.pop()
self.assertEqual(count, 26)
def test_ninesixty_castling_bug(self):
board = chess.Board("4r3/3k4/8/8/8/8/q5PP/1R1KR3 w Q - 2 2", chess960=True)
move = chess.Move.from_uci("d1b1")
self.assertTrue(board.is_castling(move))
self.assertIn(move, board.generate_pseudo_legal_moves())
self.assertTrue(board.is_pseudo_legal(move))
self.assertIn(move, board.generate_legal_moves())
self.assertTrue(board.is_legal(move))
self.assertEqual(board.parse_san("O-O-O+"), move)
self.assertEqual(board.san(move), "O-O-O+")
def test_equality(self):
self.assertEqual(chess.Board(), chess.Board())
self.assertFalse(chess.Board() != chess.Board())
a = chess.Board()
a.push_san("d4")
b = chess.Board()
b.push_san("d3")
self.assertNotEqual(a, b)
self.assertFalse(a == b)
def test_status(self):
board = chess.Board()
self.assertEqual(board.status(), chess.STATUS_VALID)
self.assertTrue(board.is_valid())
board.remove_piece_at(chess.H1)
self.assertTrue(board.status() & chess.STATUS_BAD_CASTLING_RIGHTS)
board.remove_piece_at(chess.E8)
self.assertTrue(board.status() & chess.STATUS_NO_BLACK_KING)
# The en passant square should be set even if no capture is actually
# possible.
board = chess.Board()
board.push_san("e4")
self.assertEqual(board.ep_square, chess.E3)
self.assertEqual(board.status(), chess.STATUS_VALID)
# But there must indeed be a pawn there.
board.remove_piece_at(chess.E4)
self.assertEqual(board.status(), chess.STATUS_INVALID_EP_SQUARE)
# King must be between the two rooks.
board = chess.Board("2rrk3/8/8/8/8/8/3PPPPP/2RK4 w cd - 0 1")
self.assertEqual(board.status(), chess.STATUS_BAD_CASTLING_RIGHTS)
# Generally valid position, but not valid standard chess position due
# to non-standard castling rights. Chess960 start position #0.
board = chess.Board("bbqnnrkr/pppppppp/8/8/8/8/PPPPPPPP/BBQNNRKR w KQkq - 0 1", chess960=True)
self.assertEqual(board.status(), chess.STATUS_VALID)
board = chess.Board("bbqnnrkr/pppppppp/8/8/8/8/PPPPPPPP/BBQNNRKR w KQkq - 0 1", chess960=False)
self.assertEqual(board.status(), chess.STATUS_BAD_CASTLING_RIGHTS)
def test_one_king_movegen(self):
board = chess.Board.empty()
board.set_piece_at(chess.A1, chess.Piece(chess.KING, chess.WHITE))
self.assertFalse(board.is_valid())
self.assertEqual(board.legal_moves.count(), 3)
self.assertEqual(board.pseudo_legal_moves.count(), 3)
board.push_san("Kb1")
self.assertEqual(board.legal_moves.count(), 0)
self.assertEqual(board.pseudo_legal_moves.count(), 0)
board.push_san("--")
self.assertEqual(board.legal_moves.count(), 5)
self.assertEqual(board.pseudo_legal_moves.count(), 5)
def test_epd(self):
# Create an EPD with a move and a string.
board = chess.Board("1k1r4/pp1b1R2/3q2pp/4p3/2B5/4Q3/PPP2B2/2K5 b - - 0 1")
epd = board.epd(bm=chess.Move(chess.D6, chess.D1), id="BK.01")
self.assertIn(epd, [
"1k1r4/pp1b1R2/3q2pp/4p3/2B5/4Q3/PPP2B2/2K5 b - - bm Qd1+; id \"BK.01\";",
"1k1r4/pp1b1R2/3q2pp/4p3/2B5/4Q3/PPP2B2/2K5 b - - id \"BK.01\"; bm Qd1+;"])
# Create an EPD with a noop.
board = chess.Board("4k3/8/8/8/8/8/8/4K3 w - - 0 1")
self.assertEqual(board.epd(noop=None), "4k3/8/8/8/8/8/8/4K3 w - - noop;")
# Create an EPD with a variation.
board = chess.Board("k7/8/8/8/8/8/4PPPP/4K1NR w K - 0 1")
epd = board.epd(pv=[
chess.Move.from_uci("g1f3"), # Nf3
chess.Move.from_uci("a8a7"), # Ka7
chess.Move.from_uci("e1h1"), # O-O
])
self.assertEqual(epd, "k7/8/8/8/8/8/4PPPP/4K1NR w K - pv Nf3 Ka7 O-O;")
# Create an EPD with a set of moves.
board = chess.Board("8/8/8/4k3/8/1K6/8/8 b - - 0 1")
epd = board.epd(bm=[
chess.Move.from_uci("e5e6"), # Ke6
chess.Move.from_uci("e5e4"), # Ke4
])
self.assertEqual(epd, "8/8/8/4k3/8/1K6/8/8 b - - bm Ke6 Ke4;")
# Test loading an EPD.
board = chess.Board()
operations = board.set_epd("r2qnrnk/p2b2b1/1p1p2pp/2pPpp2/1PP1P3/PRNBB3/3QNPPP/5RK1 w - - bm f4; id \"BK.24\";")
self.assertEqual(board.fen(), "r2qnrnk/p2b2b1/1p1p2pp/2pPpp2/1PP1P3/PRNBB3/3QNPPP/5RK1 w - - 0 1")
self.assertIn(chess.Move(chess.F2, chess.F4), operations["bm"])
self.assertEqual(operations["id"], "BK.24")
# Test loading an EPD with half counter operations.
board = chess.Board()
operations = board.set_epd("4k3/8/8/8/8/8/8/4K3 b - - fmvn 17; hmvc 13")
self.assertEqual(board.fen(), "4k3/8/8/8/8/8/8/4K3 b - - 13 17")
self.assertEqual(operations["fmvn"], 17)
self.assertEqual(operations["hmvc"], 13)
# Test context of parsed SANs.
board = chess.Board()
operations = board.set_epd("4k3/8/8/2N5/8/8/8/4K3 w - - test Ne4")
self.assertEqual(operations["test"], chess.Move(chess.C5, chess.E4))
# Test parsing EPD with a set of moves.
board = chess.Board()
operations = board.set_epd("4k3/8/3QK3/8/8/8/8/8 w - - bm Qe7# Qb8#;")
self.assertEqual(board.fen(), "4k3/8/3QK3/8/8/8/8/8 w - - 0 1")
self.assertEqual(len(operations["bm"]), 2)
self.assertIn(chess.Move.from_uci("d6b8"), operations["bm"])
self.assertIn(chess.Move.from_uci("d6e7"), operations["bm"])
# Test parsing EPD with a stack of moves.
board = chess.Board()
operations = board.set_epd("6k1/1p6/6K1/8/8/8/8/7Q w - - pv Qh7+ Kf8 Qf7#;")
self.assertEqual(len(operations["pv"]), 3)
self.assertEqual(operations["pv"][0], chess.Move.from_uci("h1h7"))
self.assertEqual(operations["pv"][1], chess.Move.from_uci("g8f8"))
self.assertEqual(operations["pv"][2], chess.Move.from_uci("h7f7"))
def test_null_moves(self):
self.assertEqual(str(chess.Move.null()), "0000")
self.assertEqual(chess.Move.null().uci(), "0000")
self.assertFalse(chess.Move.null())
fen = "rnbqkbnr/ppp1pppp/8/2Pp4/8/8/PP1PPPPP/RNBQKBNR w KQkq d6 0 2"
board = chess.Board(fen)
self.assertEqual(chess.Move.from_uci("0000"), board.push_san("--"))
self.assertEqual(board.fen(), "rnbqkbnr/ppp1pppp/8/2Pp4/8/8/PP1PPPPP/RNBQKBNR b KQkq - 1 2")
self.assertEqual(chess.Move.null(), board.pop())
self.assertEqual(board.fen(), fen)
def test_attackers(self):
board = chess.Board("r1b1k2r/pp1n1ppp/2p1p3/q5B1/1b1P4/P1n1PN2/1P1Q1PPP/2R1KB1R b Kkq - 3 10")
attackers = board.attackers(chess.WHITE, chess.C3)
self.assertEqual(len(attackers), 3)
self.assertIn(chess.C1, attackers)
self.assertIn(chess.D2, attackers)
self.assertIn(chess.B2, attackers)
self.assertNotIn(chess.D4, attackers)
self.assertNotIn(chess.E1, attackers)
def test_en_passant_attackers(self):
board = chess.Board("4k3/8/8/8/4pPp1/8/8/4K3 b - f3 0 1")
# Attacking the en passant square.
attackers = board.attackers(chess.BLACK, chess.F3)
self.assertEqual(len(attackers), 2)
self.assertIn(chess.E4, attackers)
self.assertIn(chess.G4, attackers)
# Not attacking the pawn directly.
attackers = board.attackers(chess.BLACK, chess.F4)
self.assertEqual(attackers, chess.BB_VOID)
def test_attacks(self):
board = chess.Board("5rk1/p5pp/2p3p1/1p1pR3/3P2P1/2N5/PP3n2/2KB4 w - - 1 26")
attacks = board.attacks(chess.E5)
self.assertEqual(len(attacks), 11)
self.assertIn(chess.D5, attacks)
self.assertIn(chess.E1, attacks)
self.assertIn(chess.F5, attacks)
self.assertNotIn(chess.E5, attacks)
self.assertNotIn(chess.C5, attacks)
self.assertNotIn(chess.F4, attacks)
self.assertFalse(board.attacks(chess.G1))
def test_clear(self):
board = chess.Board()
board.clear()
self.assertEqual(board.turn, chess.WHITE)
self.assertEqual(board.fullmove_number, 1)
self.assertEqual(board.halfmove_clock, 0)
self.assertEqual(board.castling_rights, chess.BB_VOID)
self.assertFalse(board.ep_square)
self.assertFalse(board.piece_at(chess.E1))
self.assertEqual(chess.popcount(board.occupied), 0)
def test_threefold_repetition(self):
board = chess.Board()
# Go back and forth with the nights to reach the starting position
# for a second time.
self.assertFalse(board.can_claim_threefold_repetition())
board.push_san("Nf3")
self.assertFalse(board.can_claim_threefold_repetition())
board.push_san("Nf6")
self.assertFalse(board.can_claim_threefold_repetition())
board.push_san("Ng1")
self.assertFalse(board.can_claim_threefold_repetition())
board.push_san("Ng8")
# Once more.
self.assertFalse(board.can_claim_threefold_repetition())
board.push_san("Nf3")
self.assertFalse(board.can_claim_threefold_repetition())
board.push_san("Nf6")
self.assertFalse(board.can_claim_threefold_repetition())
board.push_san("Ng1")
# Now black can go back to the starting position (thus reaching it a
# third time.)
self.assertTrue(board.can_claim_threefold_repetition())
board.push_san("Ng8")
# They indee do it. Also white can now claim.
self.assertTrue(board.can_claim_threefold_repetition())
# But not after a different move.
board.push_san("e4")
self.assertFalse(board.can_claim_threefold_repetition())