Add support for exceptions

crates/node/src/common.rs

@@ -0,0 +1,78 @@
+use alloy::{
+    network::{Network, TransactionBuilder},
+    providers::{
+        Provider, SendableTx,
+        fillers::{GasFiller, TxFiller},
+    },
+    transports::TransportResult,
+};
+
+#[derive(Clone, Debug)]
+pub struct FallbackGasFiller {
+    inner: GasFiller,
+    default_gas_limit: u64,
+    default_max_fee_per_gas: u128,
+    default_priority_fee: u128,
+}
+
+impl FallbackGasFiller {
+    pub fn new(
+        default_gas_limit: u64,
+        default_max_fee_per_gas: u128,
+        default_priority_fee: u128,
+    ) -> Self {
+        Self {
+            inner: GasFiller,
+            default_gas_limit,
+            default_max_fee_per_gas,
+            default_priority_fee,
+        }
+    }
+}
+
+impl<N> TxFiller<N> for FallbackGasFiller
+where
+    N: Network,
+{
+    type Fillable = Option<<GasFiller as TxFiller<N>>::Fillable>;
+
+    fn status(
+        &self,
+        tx: &<N as Network>::TransactionRequest,
+    ) -> alloy::providers::fillers::FillerControlFlow {
+        <GasFiller as TxFiller<N>>::status(&self.inner, tx)
+    }
+
+    fn fill_sync(&self, _: &mut alloy::providers::SendableTx<N>) {}
+
+    async fn prepare<P: Provider<N>>(
+        &self,
+        provider: &P,
+        tx: &<N as Network>::TransactionRequest,
+    ) -> TransportResult<Self::Fillable> {
+        // Try to fetch GasFiller’s “fillable” (gas_price, base_fee, estimate_gas, …)
+        // If it errors (i.e. tx would revert under eth_estimateGas), swallow it.
+        match self.inner.prepare(provider, tx).await {
+            Ok(fill) => Ok(Some(fill)),
+            Err(_) => Ok(None),
+        }
+    }
+
+    async fn fill(
+        &self,
+        fillable: Self::Fillable,
+        mut tx: alloy::providers::SendableTx<N>,
+    ) -> TransportResult<SendableTx<N>> {
+        if let Some(fill) = fillable {
+            // our inner GasFiller succeeded — use it
+            self.inner.fill(fill, tx).await
+        } else {
+            if let Some(builder) = tx.as_mut_builder() {
+                builder.set_gas_limit(self.default_gas_limit);
+                builder.set_max_fee_per_gas(self.default_max_fee_per_gas);
+                builder.set_max_priority_fee_per_gas(self.default_priority_fee);
+            }
+            Ok(tx)
+        }
+    }
+}