return err on ASM STF instead of panicking

Author: prajwolrg

crates/asm/common/src/error.rs

@@ -1,3 +1,4 @@
+use strata_primitives::l1::L1VerificationError;
 use thiserror::Error;
 
 use crate::SubprotocolId;
@@ -24,4 +25,8 @@ pub enum AsmError {
     /// Failed to serialize the state of the given subprotocol.
     #[error("failed to serialize subprotocol {0} state: {1}")]
     Serialization(SubprotocolId, #[source] borsh::io::Error),
+
+    /// L1Header do not follow consensus rules.
+    #[error("L1Header do not follow consensus rules")]
+    InvalidL1Header(#[source] L1VerificationError),
 }

crates/asm/common/src/subprotocol.rs

@@ -83,7 +83,7 @@ pub trait SubprotoHandler {
 
 /// Manages the lifecycle and execution of subprotocol handlers in the Anchor State Machine (ASM).
 ///
-/// Implementors of this trait maintain a collection of subprotocol handlers and
+/// Implementers of this trait maintain a collection of subprotocol handlers and
 /// provide methods to insert, remove, lookup, and drive execution (transactions and messages),
 /// as well as extract the final `SectionState`.
 pub trait SubprotocolManager: MsgRelayer + Sized {

crates/asm/stf/src/stage.rs

@@ -66,7 +66,8 @@ impl FinishStage {
         Self { sections }
     }
 
-    pub(crate) fn into_sections(self) -> Vec<SectionState> {
+    pub(crate) fn into_sorted_sections(mut self) -> Vec<SectionState> {
+        self.sections.sort_by_key(|state| state.id);
         self.sections
     }
 }

crates/asm/stf/src/transition.rs

@@ -3,7 +3,9 @@
 //! view into a single deterministic state transition.
 
 use bitcoin::{block::Block, params::Params};
-use strata_asm_common::{AnchorState, AsmSpec, ChainViewState, Stage, SubprotocolManager};
+use strata_asm_common::{
+    AnchorState, AsmError, AsmSpec, ChainViewState, Stage, SubprotocolManager,
+};
 use strata_asm_proto_bridge_v1::BridgeV1Subproto;
 use strata_asm_proto_core::OLCoreSubproto;
 
@@ -26,13 +28,13 @@ impl AsmSpec for StrataAsmSpec {
 
 /// Computes the next AnchorState by applying the Anchor State Machine (ASM) state transition
 /// function (STF) to the given previous state and new L1 block.
-pub fn asm_stf<S: AsmSpec>(pre_state: AnchorState, block: Block) -> AnchorState {
+pub fn asm_stf<S: AsmSpec>(pre_state: AnchorState, block: Block) -> Result<AnchorState, AsmError> {
     let mut pow_state = pre_state.chain_view.pow_state.clone();
 
     // 1. Validate and update PoW header continuity for the new block
     pow_state
         .check_and_update_continuity(&block.header, &Params::MAINNET)
-        .expect("header doesn't follow the consensus rules");
+        .map_err(AsmError::InvalidL1Header)?;
 
     // 2. Filter the relevant transactions
     let all_relevant_transactions = group_txs_by_subprotocol(&block.txdata);
@@ -51,10 +53,10 @@ pub fn asm_stf<S: AsmSpec>(pre_state: AnchorState, block: Block) -> AnchorState
     let mut finish_stage = FinishStage::new();
     S::call_subprotocols(&mut finish_stage, &mut manager);
 
-    let sections = finish_stage.into_sections();
+    let sections = finish_stage.into_sorted_sections();
     let chain_view = ChainViewState { pow_state };
-    AnchorState {
+    Ok(AnchorState {
         chain_view,
         sections,
-    }
+    })
 }