From 7e8d4df23bfa3c77ec8fc85f6f4cc13e2cd7e3f7 Mon Sep 17 00:00:00 2001
From: Giovanni Sanchez <108043524+sisyphusSmiling@users.noreply.github.com>
Date: Tue, 21 May 2024 19:15:05 -0500
Subject: [PATCH] update EVMUtils de/serialization

---
 cadence/contracts/utils/EVMUtils.cdc | 34 ++++------------------------
 1 file changed, 5 insertions(+), 29 deletions(-)

diff --git a/cadence/contracts/utils/EVMUtils.cdc b/cadence/contracts/utils/EVMUtils.cdc
index c84cc942..c4635daa 100644
--- a/cadence/contracts/utils/EVMUtils.cdc
+++ b/cadence/contracts/utils/EVMUtils.cdc
@@ -12,17 +12,7 @@ access(all) contract EVMUtils {
     // TODO: Remove once EVMAddress.toString() is available
     access(all)
     view fun getEVMAddressAsHexString(address: EVM.EVMAddress): String {
-        let bytes = address.bytes
-        // Iterating & appending to an array is not allowed in a `view` method and this method must be `view` for
-        // certain use cases in the bridge contracts - namely for emitting values in pre- & post-conditions
-        let addressBytes: [UInt8] = [
-            bytes[0], bytes[1], bytes[2], bytes[3],
-            bytes[4], bytes[5], bytes[6], bytes[7],
-            bytes[8], bytes[9], bytes[10], bytes[11],
-            bytes[12], bytes[13], bytes[14], bytes[15],
-            bytes[16], bytes[17], bytes[18], bytes[19]
-        ]
-        return String.encodeHex(addressBytes)
+        return String.encodeHex(address.bytes.toVariableSized())
     }
 
     /// Returns an EVMAddress as a hex string without a 0x prefix, truncating the string's last 20 bytes if exceeded
@@ -36,23 +26,9 @@ access(all) contract EVMUtils {
         pre {
             address.length == 40 || address.length == 42: "Invalid hex string length"
         }
-        // Remove the 0x prefix if it exists
-        let sanitized = (address[1] == "x" ? address.split(separator: "x")[1] : address).toLower()
-        if sanitized.length != 40 {
-            return nil
-        }
-        // Decode the hex string
-        var addressBytes: [UInt8] = address.decodeHex()
-        if addressBytes.length != 20 {
-            return nil
-        }
-        // Return the EVM address from the decoded hex string
-        return EVM.EVMAddress(bytes: [
-            addressBytes[0], addressBytes[1], addressBytes[2], addressBytes[3],
-            addressBytes[4], addressBytes[5], addressBytes[6], addressBytes[7],
-            addressBytes[8], addressBytes[9], addressBytes[10], addressBytes[11],
-            addressBytes[12], addressBytes[13], addressBytes[14], addressBytes[15],
-            addressBytes[16], addressBytes[17], addressBytes[18], addressBytes[19]
-        ])
+        // Strip the 0x prefix if it exists
+        var withoutPrefix = (address[1] == "x" ? address.slice(from: 2, upTo: address.length) : address).toLower()
+        let bytes = withoutPrefix.decodeHex().toConstantSized<[UInt8;20]>()!
+        return EVM.EVMAddress(bytes: bytes)
     }
 }