From 15bc6abee9cc40bd76ce6f92db3f154b1713fbee Mon Sep 17 00:00:00 2001
From: Uxio Fuentefria <uxio@safe.global>
Date: Thu, 27 Oct 2022 12:48:56 +0200
Subject: [PATCH] Refactor domain and message typehashes

---
 gnosis/safe/safe.py | 22 ++++++++++++++--------
 1 file changed, 14 insertions(+), 8 deletions(-)

diff --git a/gnosis/safe/safe.py b/gnosis/safe/safe.py
index a0f42bfcb..1d9580c6c 100644
--- a/gnosis/safe/safe.py
+++ b/gnosis/safe/safe.py
@@ -85,6 +85,12 @@ class Safe:
     GUARD_STORAGE_SLOT = (
         0x4A204F620C8C5CCDCA3FD54D003BADD85BA500436A431F0CBDA4F558C93C34C8
     )
+    DOMAIN_TYPEHASH = bytes.fromhex(
+        "47e79534a245952e8b16893a336b85a3d9ea9fa8c573f3d803afb92a79469218"
+    )
+    SAFE_MESSAGE_TYPEHASH = bytes.fromhex(
+        "60b3cbf8b4a223d68d641b3b6ddf9a298e7f33710cf3d3a9d1146b5a6150fbca"
+    )
 
     def __init__(self, address: ChecksumAddress, ethereum_client: EthereumClient):
         """
@@ -509,13 +515,14 @@ def contract(self) -> Contract:
 
     @cached_property
     def domain_separator(self):
-        domain_typehash = bytes.fromhex(
-            "47e79534a245952e8b16893a336b85a3d9ea9fa8c573f3d803afb92a79469218"
-        )
         return Web3.keccak(
             encode_abi(
                 ["bytes32", "uint256", "address"],
-                [domain_typehash, self.ethereum_client.get_chain_id(), self.address],
+                [
+                    self.DOMAIN_TYPEHASH,
+                    self.ethereum_client.get_chain_id(),
+                    self.address,
+                ],
             )
         )
 
@@ -849,11 +856,10 @@ def get_message_hash(self, message: Union[str, Hash32]) -> Hash32:
             message = message.encode()
         message_hash = fast_keccak(message)
 
-        safe_message_typehash = bytes.fromhex(
-            "60b3cbf8b4a223d68d641b3b6ddf9a298e7f33710cf3d3a9d1146b5a6150fbca"
-        )
         safe_message_hash = Web3.keccak(
-            encode_abi(["bytes32", "bytes32"], [safe_message_typehash, message_hash])
+            encode_abi(
+                ["bytes32", "bytes32"], [self.SAFE_MESSAGE_TYPEHASH, message_hash]
+            )
         )
         return Web3.keccak(
             encode_abi_packed(