fix: address review feedback from Fraser999

- Delete unused ExtractableChainShim from blobber (RethChain replaces it)
- Replace From<eyre::Report> with named RethHostError::notification()
- Handle set_backfill_thresholds(None) by restoring defaults
- Add blank line between module groups in host-reth lib.rs

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: prestwich

crates/blobber/src/lib.rs

@@ -24,7 +24,7 @@ mod error;
 pub use error::{BlobberError, BlobberResult};
 
 mod shim;
-pub use shim::{ExtractableChainShim, RecoveredBlockShim};
+pub use shim::RecoveredBlockShim;
 
 #[cfg(test)]
 mod test {

crates/blobber/src/shim.rs

@@ -1,51 +1,12 @@
 //! Shim and utilities for signet-sdk to reth conversions.
 
 use alloy::consensus::Block;
-use reth::providers::Chain;
-use signet_extract::{BlockAndReceipts, Extractable, HasTxns};
+use signet_extract::HasTxns;
 use signet_types::primitives::TransactionSigned;
 
 /// A type alias for Reth's recovered block with a signed transaction.
 type RethRecovered = reth::primitives::RecoveredBlock<Block<TransactionSigned>>;
 
-/// A shim around Reth's [`Chain`].
-#[derive(Debug)]
-#[repr(transparent)]
-pub struct ExtractableChainShim<'a> {
-    /// The underlying Reth chain.
-    chain: &'a Chain,
-}
-
-impl<'a> ExtractableChainShim<'a> {
-    /// Create a new shim around the given Reth chain.
-    pub const fn new(chain: &'a Chain) -> Self {
-        Self { chain }
-    }
-
-    /// Get a reference to the underlying Reth chain.
-    pub const fn chain(&self) -> &'a Chain {
-        self.chain
-    }
-}
-
-impl<'a> Extractable for ExtractableChainShim<'a> {
-    type Block = RecoveredBlockShim;
-    type Receipt = reth::primitives::Receipt;
-
-    fn blocks_and_receipts(
-        &self,
-    ) -> impl Iterator<Item = BlockAndReceipts<'_, Self::Block, Self::Receipt>> {
-        self.chain.blocks_and_receipts().map(|(block, receipts)| {
-            // SAFETY: `RecoveredBlockShim` is `#[repr(transparent)]` over a
-            // single `RethRecovered` field, guaranteeing identical memory
-            // layout. This makes the reference transmute sound.
-            let block =
-                unsafe { std::mem::transmute::<&'a RethRecovered, &RecoveredBlockShim>(block) };
-            BlockAndReceipts { block, receipts }
-        })
-    }
-}
-
 /// A shim for Reth's [`reth::primitives::RecoveredBlock`].
 #[derive(Debug)]
 #[repr(transparent)]

crates/host-reth/src/error.rs

@@ -17,8 +17,9 @@ pub enum RethHostError {
     MissingHeader(u64),
 }
 
-impl From<eyre::Report> for RethHostError {
-    fn from(e: eyre::Report) -> Self {
+impl RethHostError {
+    /// Wrap a notification stream error.
+    pub fn notification(e: impl Into<Box<dyn core::error::Error + Send + Sync>>) -> Self {
         Self::Notification(e.into())
     }
 }

crates/host-reth/src/lib.rs

@@ -13,6 +13,7 @@
 
 mod alias;
 pub use alias::{RethAliasOracle, RethAliasOracleFactory};
+
 mod error;
 pub use error::RethHostError;
 

crates/host-reth/src/notifier.rs

@@ -112,7 +112,7 @@ where
         let notification = self.notifications.next().await?;
         let notification = match notification {
             Ok(n) => n,
-            Err(e) => return Some(Err(e.into())),
+            Err(e) => return Some(Err(RethHostError::notification(e))),
         };
 
         // Read safe/finalized from the provider at notification time.
@@ -173,13 +173,17 @@ where
     }
 
     fn set_backfill_thresholds(&mut self, max_blocks: Option<u64>) {
-        if let Some(max_blocks) = max_blocks {
-            self.notifications.set_backfill_thresholds(ExecutionStageThresholds {
-                max_blocks: Some(max_blocks),
-                ..Default::default()
-            });
-            debug!(max_blocks, "configured backfill thresholds");
-        }
+        let thresholds = match max_blocks {
+            Some(max_blocks) => {
+                debug!(max_blocks, "configured backfill thresholds");
+                ExecutionStageThresholds { max_blocks: Some(max_blocks), ..Default::default() }
+            }
+            None => {
+                debug!("reset backfill thresholds to defaults");
+                ExecutionStageThresholds::default()
+            }
+        };
+        self.notifications.set_backfill_thresholds(thresholds);
     }
 
     fn send_finished_height(&self, block_number: u64) -> Result<(), Self::Error> {