From b3222276abea45deaf5be7bcbd875f32a7de06a6 Mon Sep 17 00:00:00 2001
From: Bruno BELANYI <bruno@belanyi.fr>
Date: Mon, 18 Jul 2022 18:21:14 +0200
Subject: [PATCH] Improve 'board::BitboardIterator'

* Accurate 'size_hint'.
* Exact size.
* Fused iterator (keeps returning 'None' after returning 'None' once).
---
 src/board/bitboard/iterator.rs | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/src/board/bitboard/iterator.rs b/src/board/bitboard/iterator.rs
index 06db283..fcd644c 100644
--- a/src/board/bitboard/iterator.rs
+++ b/src/board/bitboard/iterator.rs
@@ -14,4 +14,14 @@ impl Iterator for BitboardIterator {
             Some(crate::board::Square::from_index(lsb))
         }
     }
+
+    fn size_hint(&self) -> (usize, Option<usize>) {
+        let size = self.0.count_ones() as usize;
+
+        (size, Some(size))
+    }
 }
+
+impl ExactSizeIterator for BitboardIterator {}
+
+impl std::iter::FusedIterator for BitboardIterator {}