From f4da5bcde79ddf17c4eb2f70c41f55bcd6320f68 Mon Sep 17 00:00:00 2001
From: Damian Orzechowski <damian.orzechowski@outlook.com>
Date: Wed, 18 Sep 2024 09:53:52 +0200
Subject: [PATCH] Added constant for single byte prefix content length in RLP

---
 src/Paprika/Merkle/ComputeMerkleBehavior.cs | 2 +-
 src/Paprika/RLP/Rlp.cs                      | 5 +++--
 src/Paprika/RLP/RlpStream.cs                | 4 ++--
 3 files changed, 6 insertions(+), 5 deletions(-)

diff --git a/src/Paprika/Merkle/ComputeMerkleBehavior.cs b/src/Paprika/Merkle/ComputeMerkleBehavior.cs
index c1a2908d..bdaf61b1 100644
--- a/src/Paprika/Merkle/ComputeMerkleBehavior.cs
+++ b/src/Paprika/Merkle/ComputeMerkleBehavior.cs
@@ -650,7 +650,7 @@ private void EncodeBranch(scoped in Key key, scoped in ComputeContext ctx, scope
         var end = stream.Position;
         var actualLength = end - initialShift;
         var lengthOfLength = Rlp.LengthOfLength(actualLength);
-        if (actualLength >= 56) //to match StartSequence
+        if (actualLength >= Rlp.SmallPrefixBarrier) //to match StartSequence
             lengthOfLength++;
         var from = initialShift - lengthOfLength;
         stream.Position = from;
diff --git a/src/Paprika/RLP/Rlp.cs b/src/Paprika/RLP/Rlp.cs
index 1dadffad..e853e699 100644
--- a/src/Paprika/RLP/Rlp.cs
+++ b/src/Paprika/RLP/Rlp.cs
@@ -11,6 +11,7 @@ public static class Rlp
 {
     public const int LengthOfKeccakRlp = 33;
     public const int MaxLengthOfLength = 4;
+    public const int SmallPrefixBarrier = 56;
 
     [MethodImpl(MethodImplOptions.AggressiveInlining)]
     public static int LengthOf(in UInt256 item)
@@ -47,7 +48,7 @@ public static int LengthOf(ReadOnlySpan<byte> span)
             return 1;
         }
 
-        if (span.Length < 56)
+        if (span.Length < SmallPrefixBarrier)
         {
             return span.Length + 1;
         }
@@ -57,7 +58,7 @@ public static int LengthOf(ReadOnlySpan<byte> span)
 
     public static int LengthOfSequence(int contentLength)
     {
-        if (contentLength < 56)
+        if (contentLength < SmallPrefixBarrier)
         {
             return 1 + contentLength;
         }
diff --git a/src/Paprika/RLP/RlpStream.cs b/src/Paprika/RLP/RlpStream.cs
index 645fc245..a164b77a 100644
--- a/src/Paprika/RLP/RlpStream.cs
+++ b/src/Paprika/RLP/RlpStream.cs
@@ -24,7 +24,7 @@ public RlpStream(Span<byte> data)
 
     public void StartSequence(int contentLength)
     {
-        if (contentLength < 56)
+        if (contentLength < Rlp.SmallPrefixBarrier)
         {
             byte prefix = (byte)(192 + contentLength);
             WriteByte(prefix);
@@ -72,7 +72,7 @@ public void Encode(scoped ReadOnlySpan<byte> input)
         {
             WriteByte(input[0]);
         }
-        else if (input.Length < 56)
+        else if (input.Length < Rlp.SmallPrefixBarrier)
         {
             byte smallPrefix = (byte)(input.Length + 128);
             WriteByte(smallPrefix);