From 511e6f5a163d7242eacf1d74acd3ccc0305a5e03 Mon Sep 17 00:00:00 2001
From: Demi Obenour <demi@parity.io>
Date: Mon, 10 Aug 2020 10:05:17 +0000
Subject: [PATCH] Implement the `concat` in `twox_64_concat` (#150)

Co-authored-by: Demi M. Obenour <demiobenour@gmail.com>
---
 src/metadata.rs | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/src/metadata.rs b/src/metadata.rs
index bbaf478d8a..3ef160cfc9 100644
--- a/src/metadata.rs
+++ b/src/metadata.rs
@@ -274,7 +274,13 @@ impl StorageMetadata {
             StorageHasher::Blake2_256 => sp_core::blake2_256(bytes).to_vec(),
             StorageHasher::Twox128 => sp_core::twox_128(bytes).to_vec(),
             StorageHasher::Twox256 => sp_core::twox_256(bytes).to_vec(),
-            StorageHasher::Twox64Concat => sp_core::twox_64(bytes).to_vec(),
+            StorageHasher::Twox64Concat => {
+                sp_core::twox_64(bytes)
+                    .iter()
+                    .chain(bytes)
+                    .cloned()
+                    .collect()
+            }
         }
     }