Forced insufficient material#821

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johndoknjas:forced-insufficient-material

Commits on Apr 11, 2026

Refactor `Variant.scala` to not express `playerHasInsufficientMaterial` in terms of `opponentHasInsufficientMaterial`, and then update derived variant classes to implement their own `playerHasInsuf…
johndoknjas
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If there are legal moves for player and all of them lead to opponent (the 'player' in new positions) having insufficient mating material, then the opponent has insufficient mating material now.
johndoknjas
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Check for other conditions that are at least a draw. Also go through any non-captures first to falsify quicker.
johndoknjas
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Drops are not included in `legalMoves`!
johndoknjas
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Add tests.
johndoknjas
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Check the move did not lose first.
johndoknjas
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