From 445f94daf06a71f7be355d08e02ea9665f62aa17 Mon Sep 17 00:00:00 2001
From: Simon Gardling <titaniumtown@proton.me>
Date: Tue, 4 Mar 2025 14:10:17 -0500
Subject: [PATCH] fix shift

---
 src/repr/bitboard.rs | 5 +++--
 src/repr/board.rs    | 7 +++----
 2 files changed, 6 insertions(+), 6 deletions(-)

diff --git a/src/repr/bitboard.rs b/src/repr/bitboard.rs
index ee22f00..3e9a359 100644
--- a/src/repr/bitboard.rs
+++ b/src/repr/bitboard.rs
@@ -3,6 +3,7 @@ use super::{
     coords::{CoordPair, CoordPairInner},
     CoordAxis,
 };
+use num::PrimInt;
 use static_assertions::const_assert;
 
 #[cfg(not(feature = "bitvec"))]
@@ -45,7 +46,7 @@ impl BitBoard {
 
     // Directional shifts with edge masking (prevents wrapping)
     pub const fn east(&self) -> Self {
-        let mask = !Self::col_mask(Board::BOARD_SIZE).0; // Mask to block column 7 bits
+        let mask = !Self::col_mask(Board::BOARD_SIZE - 1).0; // Mask to block column 7 bits
         Self((self.0 & mask) << 1)
     }
 
@@ -100,7 +101,7 @@ impl BitBoard {
     }
 
     pub fn intersects(self, other: Self) -> bool {
-        (self & other).count() > 0
+        (self.0 & other.0) > 0
     }
 
     pub fn union(self, other: Self) -> Self {
diff --git a/src/repr/board.rs b/src/repr/board.rs
index cbef688..9735980 100644
--- a/src/repr/board.rs
+++ b/src/repr/board.rs
@@ -271,9 +271,8 @@ impl Board {
     /// DO NOT USE THIS ALONE, this should be called as a part of
     /// [`Board::place`] or [`Board::place_and_prop_unchecked`]
     fn propegate_from_dry(&self, coords: CoordPair, starting_color: Piece) -> BitBoard {
-        let opponent_color = starting_color.flip();
         let player_board = *self.board(starting_color);
-        let opponent_board = *self.board(opponent_color);
+        let opponent_board = *self.board(starting_color.flip());
 
         let mut flip_mask = BitBoard::new();
         let seed = BitBoard::from_coord(coords);
@@ -300,12 +299,12 @@ impl Board {
                 if current.count() == 0 || !current.intersects(opponent_board) {
                     break;
                 }
-                temp_flips = temp_flips.union(current);
+                temp_flips |= current;
             }
 
             // If terminated on a player piece, keep the flips
             if current.intersects(player_board) {
-                flip_mask = flip_mask.union(temp_flips);
+                flip_mask |= temp_flips;
             }
         }