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Perft to find bugs in move generation

22 Jun 2022

after 2 am

  • almost completed legal move generation function
  • issue: sometimes switches black and white during random play
  • issue: handling castling rights and enpassant squares while undoing a move

23 Jun 2022

after 12 am

  • bugfix: san notation doesn't show promotion
  • added perft and divide function
  • now we can find corner cases easily!

    2 am

  • wasted 1 hour on why I'm getting 1 move less than expected reason: code generates kingside else queenside castling moves 🥲

    3 am

  • bugfix: now engine checks threatened squares during castling
  • improved perft function
  • still a lot of things to do (getting wrong perft results)

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