chore: metadata hash extraction cleanup

crates/verify/src/bytecode.rs

@@ -291,7 +291,7 @@ impl VerifyBytecodeArgs {
             .await?;
 
             let match_type = crate::utils::match_bytecodes(
-                &deployed_bytecode.original_bytes(),
+                deployed_bytecode.original_byte_slice(),
                 &onchain_runtime_code,
                 &constructor_args,
                 true,
@@ -501,7 +501,7 @@ impl VerifyBytecodeArgs {
 
             // Compare the onchain runtime bytecode with the runtime code from the fork.
             let match_type = crate::utils::match_bytecodes(
-                &fork_runtime_code.original_bytes(),
+                fork_runtime_code.original_byte_slice(),
                 &onchain_runtime_code,
                 &constructor_args,
                 true,

crates/verify/src/utils.rs

@@ -197,29 +197,24 @@ fn is_partial_match(
 }
 
 fn try_extract_and_compare_bytecode(mut local_bytecode: &[u8], mut bytecode: &[u8]) -> bool {
-    local_bytecode = extract_metadata_hash(local_bytecode);
-    bytecode = extract_metadata_hash(bytecode);
+    local_bytecode = ignore_metadata_hash(local_bytecode);
+    bytecode = ignore_metadata_hash(bytecode);
 
     // Now compare the local code and bytecode
     local_bytecode == bytecode
 }
 
-/// @dev This assumes that the metadata is at the end of the bytecode
-fn extract_metadata_hash(bytecode: &[u8]) -> &[u8] {
-    // Get the last two bytes of the bytecode to find the length of CBOR metadata
-    let metadata_len = &bytecode[bytecode.len() - 2..];
-    let metadata_len = u16::from_be_bytes([metadata_len[0], metadata_len[1]]);
-
-    if metadata_len as usize <= bytecode.len() {
-        if ciborium::from_reader::<ciborium::Value, _>(
-            &bytecode[bytecode.len() - 2 - metadata_len as usize..bytecode.len() - 2],
-        )
-        .is_ok()
-        {
-            &bytecode[..bytecode.len() - 2 - metadata_len as usize]
-        } else {
-            bytecode
-        }
+/// This assumes that the metadata is at the end of the bytecode.
+fn ignore_metadata_hash(bytecode: &[u8]) -> &[u8] {
+    // Get the last two bytes of the bytecode to find the length of CBOR metadata.
+    let Some((rest, metadata_len_bytes)) = bytecode.split_last_chunk() else { return bytecode };
+    let metadata_len = u16::from_be_bytes(*metadata_len_bytes) as usize;
+    if metadata_len > rest.len() {
+        return bytecode;
+    }
+    let (rest, metadata) = rest.split_at(rest.len() - metadata_len);
+    if ciborium::from_reader::<ciborium::Value, _>(metadata).is_ok() {
+        rest
     } else {
         bytecode
     }