fix(verify-bytecode): extract constructor arguments from creation code

crates/verify/src/bytecode.rs

@@ -147,6 +147,44 @@ impl VerifyBytecodeArgs {
         };
         let etherscan = Client::new(chain, key)?;
 
+        // Get creation tx hash
+        let creation_data = etherscan.contract_creation_data(self.address).await?;
+
+        trace!(creation_tx_hash = ?creation_data.transaction_hash);
+        let mut transaction = provider
+            .get_transaction_by_hash(creation_data.transaction_hash)
+            .await
+            .or_else(|e| eyre::bail!("Couldn't fetch transaction from RPC: {:?}", e))?
+            .ok_or_else(|| {
+                eyre::eyre!("Transaction not found for hash {}", creation_data.transaction_hash)
+            })?;
+        let receipt = provider
+            .get_transaction_receipt(creation_data.transaction_hash)
+            .await
+            .or_else(|e| eyre::bail!("Couldn't fetch transaction receipt from RPC: {:?}", e))?;
+
+        let receipt = if let Some(receipt) = receipt {
+            receipt
+        } else {
+            eyre::bail!(
+                "Receipt not found for transaction hash {}",
+                creation_data.transaction_hash
+            );
+        };
+
+        // Extract creation code
+        let maybe_creation_code =
+            if receipt.to.is_none() && receipt.contract_address == Some(self.address) {
+                &transaction.input
+            } else if receipt.to == Some(DEFAULT_CREATE2_DEPLOYER) {
+                &transaction.input[32..]
+            } else {
+                eyre::bail!(
+                    "Could not extract the creation code for contract at address {}",
+                    self.address
+                );
+            };
+
         // Get the constructor args using `source_code` endpoint
         let source_code = etherscan.contract_source_code(self.address).await?;
 
@@ -168,6 +206,11 @@ impl VerifyBytecodeArgs {
                 self.build_project(&config)?
             };
 
+        let local_bytecode = artifact
+            .bytecode
+            .and_then(|b| b.into_bytes())
+            .ok_or_eyre("Unlinked bytecode is not supported for verification")?;
+
         // Get the constructor args from etherscan
         let mut constructor_args = if let Some(args) = source_code.items.first() {
             args.constructor_arguments.clone()
@@ -201,63 +244,27 @@ impl VerifyBytecodeArgs {
         .or(self.encoded_constructor_args.to_owned().map(hex::decode).transpose()?);
 
         if let Some(provided) = provided_constructor_args {
-            if provided != constructor_args && !self.json {
-                println!(
-                    "{}",
-                    format!("The provided constructor args do not match the constructor args from etherscan ({constructor_args}).")
-                        .yellow()
-                        .bold(),
-                );
-            }
             constructor_args = provided.into();
-        }
-
-        // Get creation tx hash
-        let creation_data = etherscan.contract_creation_data(self.address).await?;
-
-        trace!(creation_tx_hash = ?creation_data.transaction_hash);
-        let mut transaction = provider
-            .get_transaction_by_hash(creation_data.transaction_hash)
-            .await
-            .or_else(|e| eyre::bail!("Couldn't fetch transaction from RPC: {:?}", e))?
-            .ok_or_else(|| {
-                eyre::eyre!("Transaction not found for hash {}", creation_data.transaction_hash)
-            })?;
-        let receipt = provider
-            .get_transaction_receipt(creation_data.transaction_hash)
-            .await
-            .or_else(|e| eyre::bail!("Couldn't fetch transaction receipt from RPC: {:?}", e))?;
-
-        let receipt = if let Some(receipt) = receipt {
-            receipt
         } else {
-            eyre::bail!(
-                "Receipt not found for transaction hash {}",
-                creation_data.transaction_hash
-            );
-        };
-
-        // Extract creation code
-        let maybe_creation_code =
-            if receipt.to.is_none() && receipt.contract_address == Some(self.address) {
-                &transaction.input
-            } else if receipt.to == Some(DEFAULT_CREATE2_DEPLOYER) {
-                &transaction.input[32..]
-            } else {
-                eyre::bail!(
-                    "Could not extract the creation code for contract at address {}",
-                    self.address
-                );
-            };
+            // In some cases, Etherscan will return incorrect constructor arguments. If this
+            // happens, try extracting arguments ourselves.
+            if !maybe_creation_code.ends_with(&constructor_args) {
+                trace!("mismatch of constructor args with etherscan");
+                // If local bytecode is longer than on-chain one, this is probably not a match.
+                if maybe_creation_code.len() >= local_bytecode.len() {
+                    constructor_args =
+                        Bytes::copy_from_slice(&maybe_creation_code[local_bytecode.len()..]);
+                    trace!(
+                        "setting constructor args to latest {} bytes of bytecode",
+                        constructor_args.len()
+                    );
+                }
+            }
+        }
 
         // If bytecode_hash is disabled then its always partial verification
         let has_metadata = config.bytecode_hash == BytecodeHash::None;
 
-        let local_bytecode = artifact
-            .bytecode
-            .and_then(|b| b.into_bytes())
-            .ok_or_eyre("Unlinked bytecode is not supported for verification")?;
-
         // Append constructor args to the local_bytecode
         trace!(%constructor_args);
         let mut local_bytecode_vec = local_bytecode.to_vec();