Fix PGNs that are broken by the MacOS Stockfish app

fixpgn.py

import sys

# Get first argument
filename = sys.argv[1]

# Open the file
pgn = open(filename, "r").read().strip()

# Split it into headers and moves
pgns = pgn.split("\n\n")


clean_pgn = []
pgn_target = []

# If there are no headers, just one the moves
if len(pgns) == 1:
    pgn_target = pgns[0]
else:
    pgn_target = pgns[1]

for move in pgn_target.split("  "):
    try:
        val = int(move[0])
        clean_pgn.append(move)
    except:
        clean_pgn.append(" {" + move + "} ")

clean_gn_str = "".join(clean_pgn).replace("\n", " ")

if len(pgns) == 1:
    #print(clean_gn_str)
    with open(filename, "w") as f:
        f.write(clean_gn_str)
else:
    with open(filename, "w") as f:
        f.write("\n\n".join([pgns[0], clean_gn_str]))

Usage: python3 fixpgn.py mypgn.pgn