From 1380127b329ece4e5e5b31d77b2f1e5a0384d3e3 Mon Sep 17 00:00:00 2001
From: Hugo Demeyere <demeyere.hugo@gmail.com>
Date: Thu, 9 Jan 2025 23:01:51 +0100
Subject: [PATCH 1/2] feat(corelib): ByteArray impl Hash trait

---
 corelib/src/hash.cairo           | 13 +++++++++++++
 corelib/src/test/hash_test.cairo | 21 +++++++++++++++++++++
 2 files changed, 34 insertions(+)

diff --git a/corelib/src/hash.cairo b/corelib/src/hash.cairo
index 0eb164dc231..ae2d0fe54dc 100644
--- a/corelib/src/hash.cairo
+++ b/corelib/src/hash.cairo
@@ -229,3 +229,16 @@ impl TupleNextHash<
         state.update_with(head).update_with(rest)
     }
 }
+
+impl ByteArrayHash<S, +HashStateTrait<S>, +Drop<S>> of Hash<ByteArray, S> {
+    fn update_state(mut state: S, value: ByteArray) -> S {
+        state = state.update(value.data.len().into());
+
+        for word_index in 0..value.data.len() {
+            let word_in_data = (*value.data.at(word_index)).into();
+            state = state.update(word_in_data);
+        };
+
+        state.update(value.pending_word_len.into()).update(value.pending_word)
+    }
+}
diff --git a/corelib/src/test/hash_test.cairo b/corelib/src/test/hash_test.cairo
index 17bf43e13b3..c3046c414d6 100644
--- a/corelib/src/test/hash_test.cairo
+++ b/corelib/src/test/hash_test.cairo
@@ -85,3 +85,24 @@ fn test_user_defined_hash() {
         'Bad hash of StructForHash',
     );
 }
+
+#[test]
+fn test_byte_array_hash() {
+    let byte_array: ByteArray = "This is a sentence that is longer than 31 characters.";
+
+    let word_1 = 'This is a sentence that is long';
+    let data_length = 1;
+    let pending_word = 'er than 31 characters.';
+    let pending_word_len = 22;
+
+    assert_eq(
+        @PoseidonTrait::new().update_with(byte_array).finalize(),
+        @PoseidonTrait::new()
+            .update(data_length)
+            .update(word_1)
+            .update(pending_word_len)
+            .update(pending_word)
+            .finalize(),
+        'Bad hash for ByteArray',
+    );
+}

From a3172b42fc173390e900d460142447d6ad7b3d08 Mon Sep 17 00:00:00 2001
From: Hugo Demeyere <demeyere.hugo@gmail.com>
Date: Fri, 10 Jan 2025 16:02:39 +0100
Subject: [PATCH 2/2] feat(corelib): Added test for ByteArray hash using
 Pedersen

---
 corelib/src/test/hash_test.cairo | 23 ++++++++++++++++++++++-
 1 file changed, 22 insertions(+), 1 deletion(-)

diff --git a/corelib/src/test/hash_test.cairo b/corelib/src/test/hash_test.cairo
index c3046c414d6..c909a3bcc96 100644
--- a/corelib/src/test/hash_test.cairo
+++ b/corelib/src/test/hash_test.cairo
@@ -1,5 +1,6 @@
 use crate::hash::{HashStateExTrait, HashStateTrait};
 use crate::poseidon::PoseidonTrait;
+use crate::pedersen::PedersenTrait;
 use crate::test::test_utils::assert_eq;
 
 #[test]
@@ -103,6 +104,26 @@ fn test_byte_array_hash() {
             .update(pending_word_len)
             .update(pending_word)
             .finalize(),
-        'Bad hash for ByteArray',
+        'Bad ByteArray hash w/ Poseidon',
+    );
+
+    // Perform same test using Pedersen hashing function
+
+    let byte_array: ByteArray = "This is a sentence that is longer than 31 characters.";
+
+    let word_1 = 'This is a sentence that is long';
+    let data_length = 1;
+    let pending_word = 'er than 31 characters.';
+    let pending_word_len = 22;
+
+    assert_eq(
+        @PedersenTrait::new(0).update_with(byte_array).finalize(),
+        @PedersenTrait::new(0)
+            .update(data_length)
+            .update(word_1)
+            .update(pending_word_len)
+            .update(pending_word)
+            .finalize(),
+        'Bad ByteArray hash w/ Pedersen',
     );
 }