From 23f3d04335f1372216b0c13c650cf18262fa6ae4 Mon Sep 17 00:00:00 2001
From: Leo <luyuxuanleo@gmail.com>
Date: Tue, 1 Mar 2022 17:26:30 +0800
Subject: [PATCH] Add check for if a shard_amount is a power of two. (#186)

Signed-off-by: Leo Lu <luyuxuanleo@gmail.com>
---
 src/lib.rs | 1 +
 1 file changed, 1 insertion(+)

diff --git a/src/lib.rs b/src/lib.rs
index 2c413621..2ebffe9e 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -250,6 +250,7 @@ impl<'a, K: 'a + Eq + Hash, V: 'a, S: BuildHasher + Clone> DashMap<K, V, S> {
         shard_amount: usize,
     ) -> Self {
         assert!(shard_amount > 0);
+        assert!(shard_amount.is_power_of_two());
 
         let shift = util::ptr_size_bits() - ncb(shard_amount);