From ed38c6c12d98fc09729e18cd7ab4547f86198289 Mon Sep 17 00:00:00 2001 From: Bruno BELANYI Date: Sun, 14 Apr 2024 16:09:58 +0100 Subject: [PATCH] Add 'Bitboard::any_square' --- src/board/bitboard/mod.rs | 23 +++++++++++++++++++++++ 1 file changed, 23 insertions(+) diff --git a/src/board/bitboard/mod.rs b/src/board/bitboard/mod.rs index 9059235..81762ed 100644 --- a/src/board/bitboard/mod.rs +++ b/src/board/bitboard/mod.rs @@ -75,6 +75,12 @@ impl Bitboard { (self.0 & (self.0.wrapping_sub(1))) != 0 } + /// Return a [Square] from the board, or `None` if it is empty. + #[inline(always)] + pub fn any_square(self) -> Option { + Square::try_from_index(self.0.trailing_zeros() as usize) + } + /// Iterate over the power-set of a given [Bitboard], yielding each possible sub-set of /// [Square] that belong to the [Bitboard]. In other words, generate all set of [Square] that /// contain all, some, or none of the [Square] that are in the given [Bitboard]. @@ -479,6 +485,23 @@ mod test { ); } + #[test] + fn any_square() { + for square in Square::iter() { + assert_eq!(square.into_bitboard().any_square(), Some(square)); + } + } + + #[test] + fn any_square_empty() { + assert!(Bitboard::EMPTY.any_square().is_none()); + } + + #[test] + fn any_square_full_board() { + assert!(Bitboard::ALL.any_square().is_some()); + } + #[test] fn into_square() { for square in Square::iter() {