feat(cast): cast send tries to decode custom errors

crates/cast/bin/cmd/send.rs

@@ -1,19 +1,21 @@
 use crate::tx::{self, CastTxBuilder};
+use alloy_json_rpc::RpcError;
 use alloy_network::{AnyNetwork, EthereumWallet};
 use alloy_provider::{Provider, ProviderBuilder};
 use alloy_rpc_types::TransactionRequest;
 use alloy_serde::WithOtherFields;
 use alloy_signer::Signer;
-use alloy_transport::Transport;
+use alloy_transport::{Transport, TransportErrorKind};
 use cast::Cast;
 use clap::Parser;
-use eyre::Result;
+use eyre::{eyre, Result};
 use foundry_cli::{
     opts::{EthereumOpts, TransactionOpts},
     utils,
 };
-use foundry_common::ens::NameOrAddress;
+use foundry_common::{ens::NameOrAddress, selectors::pretty_calldata};
 use foundry_config::Config;
+use serde_json::Value;
 use std::{path::PathBuf, str::FromStr};
 
 /// CLI arguments for `cast send`.
@@ -166,7 +168,59 @@ impl SendTxArgs {
 
             tx::validate_from_address(eth.wallet.from, from)?;
 
-            let (tx, _) = builder.build(&signer).await?;
+            let res = builder.build(&signer).await;
+
+            let (tx, _) = match res {
+                Err(report) => {
+                    // Try to downcast the error to ErrorPayload
+                    if let Some(RpcError::ErrorResp(error_payload)) =
+                        report.downcast_ref::<RpcError<TransportErrorKind>>()
+                    {
+                        // 1. Return if it's not a revert
+                        if error_payload.code != 3 {
+                            return Err(report);
+                        }
+                        // 2. Extract the error data from the ErrorPayload
+                        let error_data = match error_payload.data.clone() {
+                            Some(data) => data,
+                            None => {
+                                return Err(report);
+                            }
+                        };
+
+                        let error_data: Value = match serde_json::from_str(error_data.get()) {
+                            Ok(data) => data,
+                            Err(e) => {
+                                tracing::warn!("Failed to deserialize error data: {e}");
+                                return Err(eyre!(e));
+                            }
+                        };
+                        let error_data_string = error_data.as_str().unwrap_or_default();
+
+                        // Check if it's a revert string (has an Error(string) signature)
+                        if error_data_string.starts_with("0x08c379a0") {
+                            return Err(report);
+                        }
+
+                        let pretty_calldata = match pretty_calldata(error_data_string, false).await
+                        {
+                            Ok(pretty_calldata) => pretty_calldata,
+                            Err(e) => {
+                                tracing::warn!("Failed to pretty print calldata: {e}");
+                                return Err(report);
+                            }
+                        };
+
+                        let detailed_report = report
+                            .wrap_err(format!("Reverted with custom error: {pretty_calldata}"));
+
+                        return Err(detailed_report);
+                    }
+                    // If it's not an ErrorPayload, return the original error
+                    return Err(report);
+                }
+                Ok(result) => result,
+            };
 
             let wallet = EthereumWallet::from(signer);
             let provider = ProviderBuilder::<_, _, AnyNetwork>::default()

crates/cast/tests/cli/main.rs

@@ -1412,6 +1412,74 @@ casttest!(block_number_hash, |_prj, cmd| {
     assert_eq!(s.trim().parse::<u64>().unwrap(), 1, "{s}")
 });
 
+// ... existing code ...
+
+casttest!(send_custom_error, async |prj, cmd| {
+    // Start anvil
+    let (_api, handle) = anvil::spawn(NodeConfig::test()).await;
+    let endpoint = handle.http_endpoint();
+
+    prj.add_source(
+        "SimpleStorage",
+        r#"
+    contract SimpleStorage {
+
+    error ValueTooHigh(uint256 providedValue, uint256 maxValue);
+
+    function setValueTo101() public {
+        revert ValueTooHigh({ providedValue: 101, maxValue: 100 });
+    }
+}
+    "#,
+    )
+    .unwrap();
+
+    // Deploy the contract
+    let output = cmd
+        .forge_fuse()
+        .args([
+            "create",
+            "./src/SimpleStorage.sol:SimpleStorage",
+            "--rpc-url",
+            &endpoint,
+            "--broadcast",
+            "--private-key",
+            "0xac0974bec39a17e36ba4a6b4d238ff944bacb478cbed5efcae784d7bf4f2ff80",
+        ])
+        .assert_success()
+        .get_output()
+        .stdout_lossy();
+
+    let address = output.split("Deployed to: ").nth(1).unwrap().split('\n').next().unwrap().trim();
+    let contract_address = address.trim();
+
+    // Call the function that always reverts
+    cmd.cast_fuse()
+        .args([
+            "send",
+            contract_address,
+            "setValueTo101()",
+            "--rpc-url",
+            &endpoint,
+            "--private-key",
+            "0xac0974bec39a17e36ba4a6b4d238ff944bacb478cbed5efcae784d7bf4f2ff80",
+        ])
+        .assert_failure()
+        .stderr_eq(str![[r#"
+Error: Reverted with custom error: 
+ Possible methods:
+ - ValueTooHigh(uint256,uint256)
+ ------------
+ [000]: 0000000000000000000000000000000000000000000000000000000000000065
+ [020]: 0000000000000000000000000000000000000000000000000000000000000064
+
+
+Context:
+- server returned an error response: error code 3: execution reverted: custom error 0x7a0e1985: ed, data: "0x7a0e198500000000000000000000000000000000000000000000000000000000000000650000000000000000000000000000000000000000000000000000000000000064"
+
+"#]]);
+});
+
 casttest!(send_eip7702, async |_prj, cmd| {
     let (_api, handle) =
         anvil::spawn(NodeConfig::test().with_hardfork(Some(EthereumHardfork::PragueEOF.into())))