Distinguish between standard and chess960 From Position games#1147
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AttackingOrDefending merged 2 commits intolichess-bot-devs:masterfrom Oct 15, 2025
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A "From Position" game can encode a chess960 position, which would allow chess960 challenges to bots that don't support them, leading to errors. This change checks the FEN string to see if it is a 960 game and declines the challenge if the bot does not play them.
AttackingOrDefending
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Oct 14, 2025
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Is this ready to be merged, or do we wait for resolution to the weird castling fen described in the issue? |
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It's ready to merge. The varying FENs from lichess are handled by python-chess. I may write a bug report to lichess at some point in the future. There's nothing to do about it here and it doesn't cause problems. |
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…s-bot-devs#1147) * Distinguish standard and 960 From Position games * Prevent chess960 challenges to unsupported bots A "From Position" game can encode a chess960 position, which would allow chess960 challenges to bots that don't support them, leading to errors. This change checks the FEN string to see if it is a 960 game and declines the challenge if the bot does not play them.
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Type of pull request:
Description:
There is no indication in the GameFullEvent whether a From Position game uses Chess960 rules or not. This change determines what kind of game is being played by seeing whether the
chess.Boardoptionchess960=Truechanges the state of the board. If it does, then the game is a 960 game.Related Issues:
Closes #1146
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