testsAndMisc/python_pkg/lichess_bot/tests/test_puzzles.py
Krzysztof kuhy Rudnicki 26860233af fix(lint): fix G004 and PTH123 violations across codebase
- Convert f-string logging to % style (G004)
- Convert open() to Path.open() (PTH123)
- Remove G004 and PTH123 from global ignores in pyproject.toml
2025-11-30 23:57:49 +01:00

82 lines
2.8 KiB
Python

"""Test the engine against Lichess puzzles."""
import csv
from pathlib import Path
import chess
import pytest
from python_pkg.lichess_bot.engine import RandomEngine
_PUZZLE_CSV = Path(__file__).parent / "lichess_db_puzzle.csv"
def _load_top_puzzles(csv_path: str | Path, limit: int = 8) -> list[tuple[str, str]]:
"""Return a list of (FEN, solution_moves_str) for the first `limit` rows in the CSV.
CSV columns: PuzzleId,FEN,Moves,...
"""
puzzles: list[tuple[str, str]] = []
if not Path(csv_path).is_file():
return puzzles
with Path(csv_path).open(newline="", encoding="utf-8") as f:
reader = csv.DictReader(f)
for row in reader:
fen = row["FEN"].strip()
moves = row["Moves"].strip()
if fen and moves:
puzzles.append((fen, moves))
if len(puzzles) >= limit:
break
return puzzles
_PUZZLES = _load_top_puzzles(_PUZZLE_CSV, limit=8)
@pytest.mark.skipif(not _PUZZLES, reason="Puzzle CSV not found")
@pytest.mark.parametrize(
("fen", "moves_str"),
_PUZZLES or [("rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1", "e2e4")],
)
def test_puzzle_engine_follow_solution(fen: str, moves_str: str) -> None:
"""Verify the engine follows puzzle solutions correctly."""
board = chess.Board(fen)
eng = RandomEngine(max_time_sec=1.0)
# Moves are space-separated UCIs alternating sides
# starting from side-to-move in the FEN
solution_moves = moves_str.split()
for step, uci in enumerate(solution_moves, start=1):
# Engine move on this ply
mv, expl = eng.choose_move_with_explanation(board, time_budget_sec=0.5)
assert mv is not None, f"No move returned at step {step}.\nExplanation: {expl}"
# If engine move differs from solution, fail immediately
# but provide analysis of the correct move
if mv.uci() != uci:
# Ask the engine to analyze the correct move for debug
score_cp, proposed_expl, best_mv, best_expl = (
eng.evaluate_proposed_move_with_suggestion(
board, uci, time_budget_sec=0.5
)
)
details = [
f"Puzzle failed at step {step}.",
f"FEN: {fen}",
f"Expected: {uci}",
f"Engine played: {mv.uci()}",
"--- engine explanation ---",
expl,
"--- analysis of expected move ---",
f"score_cp: {score_cp}",
proposed_expl,
]
if best_mv is not None:
details.append("--- engine best move analysis ---")
details.append(best_expl)
pytest.fail("\n".join(details))
# Apply the move and continue
board.push(mv)