From 646874eca848c9b8336a6d1a4b32bd4388f3a795 Mon Sep 17 00:00:00 2001
From: chachaleo <charlotte.leo@hotmail.com>
Date: Tue, 17 Oct 2023 17:28:38 +0700
Subject: [PATCH 1/3] modification function from_byte

---
 crates/utils/src/helpers.cairo | 37 ++++++++++++++++++++++++++++++----
 1 file changed, 33 insertions(+), 4 deletions(-)

diff --git a/crates/utils/src/helpers.cairo b/crates/utils/src/helpers.cairo
index 5153a7e16..826ae240f 100644
--- a/crates/utils/src/helpers.cairo
+++ b/crates/utils/src/helpers.cairo
@@ -7,6 +7,8 @@ use utils::constants::{
     POW_256_16,
 };
 use keccak::u128_split;
+use traits::DivRem;
+use integer::U32TryIntoNonZero;
 
 
 /// Ceils a number of bits to the next word (32 bytes)
@@ -530,12 +532,39 @@ impl ByteArrayExt of ByteArrayExTrait {
         // we can just deserialize bytes by chunks of 31, skipping pending_word
         // checks
         let mut arr: ByteArray = Default::default();
+        let (mut q, mut r) = DivRem::div_rem(bytes.len(), 31_u32.try_into().unwrap());
         loop {
-            match bytes.pop_front() {
-                Option::Some(byte) => { arr.append_byte(*byte); },
-                Option::None => { break; }
-            }
+            if q == 0 {
+                break;
+            };
+            let mut word: felt252 = 0;
+            let mut i = 0;
+            loop {
+                if i == 31 {
+                    break;
+                };
+                word = word * POW_256_1.into() + (*bytes.pop_front().unwrap()).into();
+                i += 1;
+            };
+            arr.data.append(word.try_into().unwrap()); 
+            q -= 1;
+        };
+
+        if r == 0 {
+            return arr;
+        };
+
+        arr.pending_word_len = r;
+        let mut pending_word: felt252 = 0;
+
+        loop {
+            if r == 0 {
+                break;
+            };
+            pending_word = pending_word * POW_256_1.into() + (*bytes.pop_front().unwrap()).into();
+            r -= 1;
         };
+        arr.pending_word = pending_word;
         arr
     }
 }

From 6b6cc01c8bafc67abaf954d4124680ed374fee60 Mon Sep 17 00:00:00 2001
From: chachaleo <charlotte.leo@hotmail.com>
Date: Tue, 17 Oct 2023 19:03:01 +0700
Subject: [PATCH 2/3] modif in from_bytes

---
 crates/utils/src/helpers.cairo | 29 +++++++++++++++--------------
 1 file changed, 15 insertions(+), 14 deletions(-)

diff --git a/crates/utils/src/helpers.cairo b/crates/utils/src/helpers.cairo
index 826ae240f..2eb94f6b2 100644
--- a/crates/utils/src/helpers.cairo
+++ b/crates/utils/src/helpers.cairo
@@ -528,42 +528,43 @@ impl U256Impl of U256Trait {
 #[generate_trait]
 impl ByteArrayExt of ByteArrayExTrait {
     fn from_bytes(mut bytes: Span<u8>) -> ByteArray {
-        //TODO(eni): optimize deserialization of Span<u8> to ByteArray;
-        // we can just deserialize bytes by chunks of 31, skipping pending_word
-        // checks
         let mut arr: ByteArray = Default::default();
-        let (mut q, mut r) = DivRem::div_rem(bytes.len(), 31_u32.try_into().unwrap());
+        let (mut nb_full_words, mut pending_word_len) = DivRem::div_rem(
+            bytes.len(), 31_u32.try_into().unwrap()
+        );
+        let mut i = 0;
         loop {
-            if q == 0 {
+            if i == nb_full_words {
                 break;
             };
             let mut word: felt252 = 0;
-            let mut i = 0;
+            let mut j = 0;
             loop {
-                if i == 31 {
+                if j == 31 {
                     break;
                 };
                 word = word * POW_256_1.into() + (*bytes.pop_front().unwrap()).into();
-                i += 1;
+                j += 1;
             };
-            arr.data.append(word.try_into().unwrap()); 
-            q -= 1;
+            arr.data.append(word.try_into().unwrap());
+            i += 1;
         };
 
-        if r == 0 {
+        if pending_word_len == 0 {
             return arr;
         };
 
-        arr.pending_word_len = r;
         let mut pending_word: felt252 = 0;
+        let mut i = 0;
 
         loop {
-            if r == 0 {
+            if i == pending_word_len {
                 break;
             };
             pending_word = pending_word * POW_256_1.into() + (*bytes.pop_front().unwrap()).into();
-            r -= 1;
+            i += 1;
         };
+        arr.pending_word_len = pending_word_len;
         arr.pending_word = pending_word;
         arr
     }

From 9605b49b546020bcf11e02f2968f51e4d67b09e4 Mon Sep 17 00:00:00 2001
From: Charlotte <49371958+chachaleo@users.noreply.github.com>
Date: Wed, 18 Oct 2023 11:27:20 +0700
Subject: [PATCH 3/3] Update crates/utils/src/helpers.cairo

Co-authored-by: Mathieu <60658558+enitrat@users.noreply.github.com>
---
 crates/utils/src/helpers.cairo | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/crates/utils/src/helpers.cairo b/crates/utils/src/helpers.cairo
index 2eb94f6b2..b77d329e9 100644
--- a/crates/utils/src/helpers.cairo
+++ b/crates/utils/src/helpers.cairo
@@ -529,7 +529,7 @@ impl U256Impl of U256Trait {
 impl ByteArrayExt of ByteArrayExTrait {
     fn from_bytes(mut bytes: Span<u8>) -> ByteArray {
         let mut arr: ByteArray = Default::default();
-        let (mut nb_full_words, mut pending_word_len) = DivRem::div_rem(
+        let (nb_full_words, pending_word_len) = DivRem::div_rem(
             bytes.len(), 31_u32.try_into().unwrap()
         );
         let mut i = 0;