fixup: Add test that both exhuasts and returns a result

src/branch_and_bound.rs

@@ -827,4 +827,35 @@ mod tests {
 
         assert!(list.is_none());
     }
+
+    #[test]
+    fn select_coins_bnb_exhaust_with_result() {
+        // This returns a result AND hits the iteration exhaust limit.
+
+        // Takes 163,819 iterations (hits the iteration limit).
+        let base: usize = 2;
+        let mut target = 0;
+        let vals = (0..15).enumerate().flat_map(|(i, _)| {
+            let a = base.pow(15 + i as u32) as u64;
+            target += a;
+            vec![a, a + 2]
+        });
+
+        let mut vals: Vec<_> = vals.map(Amount::from_sat).collect();
+
+        // Add a value that will match the target before iteration exhaustion occurs.
+        vals.push(Amount::from_sat(target));
+        let weighted_utxos = create_weighted_utxos_from_values(vals);
+        let mut list = select_coins_bnb(
+            Amount::from_sat(target),
+            Amount::ONE_SAT,
+            FeeRate::ZERO,
+            FeeRate::ZERO,
+            &weighted_utxos,
+        )
+        .unwrap();
+
+        assert_eq!(list.len(), 1);
+        assert_eq!(list.next().unwrap().utxo.value, Amount::from_sat(target));
+    }
 }