How to correctly send extra uci commands using this library - like isready, and ucinewgame messages

[JohanSjoblom]

Background
I have ported Picochess from the older python-chess to this new chess library (https://github.com/JohanSjoblom/picochess).
All the new and modern chess engines work well. I also need to support older engines (mame, retro, and very special ones). For these I have to send extra uci messages like "isready" and "ucinewgame" in a specific order even if they have already been sent earlier by the library. Currently I got some old engines working by using the UciProtocol.send_line() function to do this.

My questions are basically:

1. is the send_line the proper way to send these uci messages (it seems to work). Is there a better way? I see that there are internal functions _isready() and _ucinewgame() but they are not public functions. Should I use them anyway, and if so, could they be promoted to public (ie without the front underscore).

2. how would I wait for the answer to "isready"... The purpose of isready is to give the chess engine time to finish setup... and the above mentioned function send_line() does not support async wait... In fact it does not return anything. So how would I wait for a chess engine to be ready with this new chess library? Should I use UciProtocol.line_received() and wait for the correct answer? In that case I of course take the risk that the code will hang if the chess engine does not respond.

Appreciate any ideas or comments on this. BR, Johan

[MarkZH]

Directly using send_line() usually isn't the correct way to communicate with an engine. To send isready, use the ping() method, which also waits for the response from the engine, whether through awaiting or using the synchronous SimpleEngine classes.

[JohanSjoblom]

Thank you, great stuff :-) For "normal modern engines" I don't need to send any extra messages. This need comes from supporting old very special and retro engines. So with a switch like "emulate old Picochess behaviour" I would send these extra messages.

• I use async yes, so this will solve the isready "extra" message need.
• Would you have any suggestion on how to send an extra "ucinewgame" using this library?

[MarkZH]

The play() method has a game parameter that can be used for this. That parameter can take any value of any type (int, str, etc). If a call to play() is given a different game value, ucinewgame (or new to XBoard engines) will be sent to the engine.

[JohanSjoblom]

Thanks again! Question answered!