def test_game_over_position(self):
board = chess.Board('2Q5/k7/5B2/2P5/5RK1/6P1/8/8 w - - 1 57')
puzzle = Puzzle(board, board.parse_san('Bd4'))
puzzle.generate(depth=SEARCH_DEPTH)
self.assertFalse(puzzle.is_complete())
board = chess.Board('2Q5/k7/8/2P5/3B1RK1/6P1/8/8 b - - 2 57')
puzzle = Puzzle(board)
puzzle.generate(depth=SEARCH_DEPTH)
self.assertFalse(puzzle.is_complete())
def test_mate_in_3_is_complete_2(self):
# 1... Qxf2+ 2. Rxf2 Rxf2+ 3. Kh1 Ng3#
board = chess.Board(
'r2n1rk1/1ppb2pp/1p1p4/3Ppq1n/2B3P1/2P4P/PP1N1P1K/R2Q1RN1 b - - 0 1'
)
puzzle = Puzzle(board, board.parse_san('Qxf2+'))
puzzle.generate(depth=SEARCH_DEPTH)
self.assertTrue(puzzle.player_moves_first)
self.assertEqual(puzzle.category(), "Mate")
def find_puzzle_candidates(game: Game, scan_depth=SCAN_DEPTH) -> List[Puzzle]:
""" finds puzzle candidates from a chess game
"""
log(Color.DIM, "Scanning game for puzzles (depth: %d)..." % scan_depth)
prev_score = Cp(0)
puzzles = []
i = 0
node = game
while not node.is_end():
next_node = node.variation(0)
next_board = next_node.board()
cur_score = AnalysisEngine.best_move(next_board, scan_depth).score
board = node.board()
highlight_move = False
if should_investigate(prev_score, cur_score, board):
highlight_move = True
puzzle = Puzzle(
board,
next_node.move,
)
puzzles.append(puzzle)
log_move(board, next_node.move, cur_score, highlight=highlight_move)
prev_score = cur_score
node = next_node
i += 1
return puzzles
def test_mate_in_3_is_complete_3(self):
# 1. Rxh7+ Kxh7 2. Rh1+ Kg7 3. Qh6#
board = chess.Board(
'3q1r1k/2p4p/1p1pBrp1/p2Pp3/2PnP3/5PP1/PP1Q2K1/5R1R w - - 1 0')
puzzle = Puzzle(board, board.parse_san('Rxh7+'))
puzzle.generate(depth=SEARCH_DEPTH)
self.assertTrue(puzzle.is_complete())
self.assertTrue(puzzle.player_moves_first)
self.assertEqual(puzzle.category(), "Mate")
expected_uci_moves = ['h1h7', 'h8h7', 'f1h1', 'h7g7', 'd2h6']
self.assertEqual([str(p.initial_move) for p in puzzle.positions],
expected_uci_moves)
game = chess.pgn.read_game(io.StringIO(puzzle.to_pgn()))
self.assertEqual([m.uci() for m in game.mainline_moves()][:5],
expected_uci_moves)
def test_puzzles_loaded_from_pgn(self):
with pgn_file_path("wtharvey.pgn") as f:
game = chess.pgn.read_game(f)
puzzle = Puzzle(game.board())
puzzle.generate(depth=14)
self.assertTrue(puzzle.is_complete())
self.assertTrue(puzzle.category() == "Material")
self.assertTrue(puzzle.player_moves_first)
self.assertEqual(
[m.uci() for m in game.mainline_moves()],
[str(p.initial_move) for p in puzzle.positions],
)
def test_mate_in_3_is_complete_1(self):
# 1. Qxh8+ Kxh8 2. Bf6+ Kg8 3. Re8#
board = chess.Board(
'r1b3kr/ppp1Bp1p/1b6/n2P4/2p3q1/2Q2N2/P4PPP/RN2R1K1 w - - 1 0')
puzzle = Puzzle(board)
puzzle.generate(depth=SEARCH_DEPTH)
self.assertTrue(puzzle.is_complete())
self.assertTrue(puzzle.player_moves_first)
self.assertEqual(puzzle.category(), "Mate")
# self.assertTrue(len(puzzle.positions) == 5)
expected_uci_moves = ['c3h8', 'g8h8', 'e7f6']
self.assertEqual([str(p.initial_move) for p in puzzle.positions][:3],
expected_uci_moves)
game = chess.pgn.read_game(io.StringIO(puzzle.to_pgn()))
self.assertEqual([m.uci() for m in game.mainline_moves()][:3],
expected_uci_moves)
def test_bishop_fork(self):
# source https://lichess.org/training/61079
# source game https://lichess.org/1n12OmvV
# 34. Rb7
board = chess.Board(
'6k1/R4p2/1r3npp/2N5/P1b2P2/6P1/3r2BP/4R1K1 w - - 0 34')
puzzle = Puzzle(board, board.parse_san('Rb7'))
puzzle.generate(depth=15)
self.assertTrue(puzzle.is_complete())
self.assertFalse(puzzle.player_moves_first)
self.assertEqual(puzzle.category(), "Material")
expected_uci_moves = ['a7b7', 'd2g2', 'g1g2', 'c4d5', 'g2g1', 'd5b7']
self.assertEqual([str(p.initial_move) for p in puzzle.positions][:6],
expected_uci_moves)
game = chess.pgn.read_game(io.StringIO(puzzle.to_pgn()))
self.assertEqual([m.uci() for m in game.mainline_moves()][:6],
expected_uci_moves)
def test_threefold_repetition_detection(self):
# https://lichess.org/tYLGlqsX
# 21... Be6??
board = chess.Board(
'r1b2r1k/ppp2p1p/8/P3p2p/2PqP3/3P1Q1P/6PK/5R2 b - - 3 21')
puzzle = Puzzle(board, board.parse_san('Be6'))
puzzle.generate(depth=SEARCH_DEPTH)
self.assertTrue(puzzle.is_complete())
self.assertFalse(puzzle.player_moves_first)
self.assertEqual(puzzle.category(), "Equalize")
# test that the puzzle stops at a threefold repetition position
expected_uci_moves = [
'c8e6', 'f3f6', 'h8g8', 'f6g5', 'g8h8', 'g5f6', 'h8g8', 'f6g5',
'g8h8'
]
self.assertEqual([str(p.initial_move) for p in puzzle.positions],
expected_uci_moves)
game = chess.pgn.read_game(io.StringIO(puzzle.to_pgn()))
self.assertEqual([m.uci() for m in game.mainline_moves()],
expected_uci_moves)
def test_puzzle_is_not_complete(self):
board = chess.Board()
puzzle = Puzzle(board, chess.Move.from_uci("e2e4"))
puzzle.generate(depth=SEARCH_DEPTH)
self.assertFalse(puzzle.is_complete())
def test_crash(self):
board = chess.Board('8/p6P/R7/2q5/1p1b4/1kp5/5PP1/3Q2K1 b - - 9 44')
puzzle = Puzzle(board, board.parse_san('Kc4'))
puzzle.generate(depth=SEARCH_DEPTH)
self.assertFalse(puzzle.is_complete())
self.assertTrue(puzzle.category() == "Mate")
def test_puzzles_without_initial_move(self):
depth = 14
# https://www.chesstactics.org/removing-the-guard
# Figure 5.1.1.1
board = chess.Board(
'3rr1k1/ppq2pp1/2p1b2p/8/3P2n1/2N3P1/PP3PBP/R2QR1K1 w - - 0 1')
puzzle = Puzzle(board)
puzzle.generate(depth=depth)
self.assertTrue(puzzle.is_complete())
self.assertTrue(puzzle.player_moves_first)
self.assertEqual(puzzle.category(), "Material")
# Figure 5.1.1.2
board = chess.Board('1k6/p7/1p1prrB1/7P/4R3/2P3K1/PP3P2/8 b - - 0 1')
puzzle = Puzzle(board)
puzzle.generate(depth=depth)
self.assertTrue(puzzle.is_complete())
self.assertTrue(puzzle.player_moves_first)
self.assertEqual(puzzle.category(), "Material")
expected_uci_moves = ['f6g6', 'h5g6', 'e6e4', 'f2f4']
self.assertEqual([str(p.initial_move) for p in puzzle.positions],
expected_uci_moves)
# Figure 5.1.1.3
board = chess.Board('8/1p6/p3pk2/5nR1/8/P3rN2/1P3KP1/8 w - - 0 1')
puzzle = Puzzle(board)
puzzle.generate(depth=depth)
self.assertTrue(puzzle.is_complete())
self.assertTrue(puzzle.category() == "Material")
self.assertTrue(puzzle.player_moves_first)
expected_uci_moves = ['g5f5', 'f6f5', 'f2e3']
self.assertEqual([str(p.initial_move) for p in puzzle.positions[:3]],
expected_uci_moves)
# Figure 5.4.1.2
board = chess.Board(
'6rk/p3qp2/1np5/2b1pP2/4P1nr/1BN2Q2/PP3P2/3R1K1R w - - 0 1')
puzzle = Puzzle(board)
puzzle.generate(depth=depth)
self.assertTrue(puzzle.is_complete())
self.assertTrue(puzzle.category() == "Material")
self.assertTrue(puzzle.player_moves_first)
expected_uci_moves = ['f5f6', 'e7f6', 'f3f6', 'g4f6', 'h1h4', 'h8g7']
self.assertEqual([str(p.initial_move) for p in puzzle.positions],
expected_uci_moves)
# http://wtharvey.com/a01.html
# Juan Bellon Lopez vs Ljubomir Ljubojevic, Palma de Majorca, 1972
board = chess.Board(
'r2qr3/2pp1pkp/b1p3p1/p7/P7/1PnBPQ2/2PN1PPP/R4RK1 w - - 0 1')
puzzle = Puzzle(board)
puzzle.generate(depth=14)
self.assertTrue(puzzle.is_complete())
self.assertTrue(puzzle.category() == "Material")
self.assertTrue(puzzle.player_moves_first)
configure_logging(level=logging.INFO)
else:
configure_logging(level=logging.DEBUG)
def print_puzzle_pgn(puzzle, pgn_headers=None):
puzzle_pgn = puzzle.to_pgn(pgn_headers=pgn_headers)
log(Color.MAGENTA, "NEW PUZZLE GENERATED\n")
print(Color.CYAN + puzzle_pgn + "\n\n" + Color.ENDC)
# load a FEN and try to create a puzzle from it
if settings.fen:
log(Color.DIM, AnalysisEngine.name())
puzzle = Puzzle(Board(settings.fen))
puzzle.generate(depth=settings.search_depth)
if puzzle.is_complete():
print_puzzle_pgn(puzzle)
engine.quit()
exit(0)
# load games from a PGN and scan them for puzzles
n_positions = 0 # number of positions considered
n_puzzles = 0 # number of puzzles generated
game_id = 0
pgn = open(settings.pgn, "r")
while game_id < settings.start_index:
game = chess.pgn.read_game(pgn)