From ab587f379fa7967bd71b2b7e22fd44879e08e894 Mon Sep 17 00:00:00 2001
From: Eryn Wells <eryn@erynwells.me>
Date: Sat, 24 May 2025 17:54:46 -0700
Subject: [PATCH] [board] Fix a bug in PieceSet::opposing_occupancy

This method should compute occupancy of everything except the provided color. Instead
it was computing the inverse.
---
 board/src/piece_sets.rs | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/board/src/piece_sets.rs b/board/src/piece_sets.rs
index d3d7fde..97ada5c 100644
--- a/board/src/piece_sets.rs
+++ b/board/src/piece_sets.rs
@@ -69,13 +69,15 @@ impl PieceSet {
     }
 
     pub fn opposing_occupancy(&self, color: Color) -> BitBoard {
+        let color_index = color as usize;
+
         self.color_occupancy.iter().enumerate().fold(
             BitBoard::default(),
             |acc, (index, occupancy)| {
-                if index == color as usize {
-                    acc | occupancy
-                } else {
+                if index == color_index {
                     acc
+                } else {
+                    acc | occupancy
                 }
             },
         )