From a9a0c1ba786e89911dc9e24d55a756b8641f5c44 Mon Sep 17 00:00:00 2001
From: Dmitriy Ryajov <dryajov@gmail.com>
Date: Sat, 16 Dec 2023 22:40:50 -0600
Subject: [PATCH] don't pad unless needed

---
 poseidon2/io.nim | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/poseidon2/io.nim b/poseidon2/io.nim
index 2c8dd6b..346321b 100644
--- a/poseidon2/io.nim
+++ b/poseidon2/io.nim
@@ -33,9 +33,10 @@ iterator elements*(bytes: openArray[byte], _: type F): F =
     let element = F.fromOpenArray(bytes.toOpenArray(chunkStart, chunkEnd))
     yield element
     chunkStart += chunkLen
-  let finalChunk = bytes[chunkStart..<bytes.len] & endMarker
-  let finalElement = F.fromOpenArray(finalChunk)
-  yield finalElement
+  if bytes.len - chunkStart > 0:
+    let finalChunk = bytes[chunkStart..<bytes.len] & endMarker
+    let finalElement = F.fromOpenArray(finalChunk)
+    yield finalElement
 
 # Remark: since `fromInt()` does not work at compile time, this doesn't either
 func toF*(a: SomeInteger | SomeUnsignedInt) : F =