chore: minor MAST module cleanup (#1407)

* refactor: remove MerkleTreeNode trait
* chore: added comments and section separators
* fix: remove implicit serialization of MastNodeId

assembly/src/assembler/mast_forest_builder.rs

@@ -3,7 +3,7 @@ use core::ops::Index;
 use alloc::{collections::BTreeMap, vec::Vec};
 use vm_core::{
     crypto::hash::RpoDigest,
-    mast::{MastForest, MastForestError, MastNode, MastNodeId, MerkleTreeNode},
+    mast::{MastForest, MastForestError, MastNode, MastNodeId},
     DecoratorList, Operation,
 };
 

assembly/src/assembler/mod.rs

@@ -11,7 +11,7 @@ use crate::{
 use alloc::{boxed::Box, sync::Arc, vec::Vec};
 use mast_forest_builder::MastForestBuilder;
 use vm_core::{
-    mast::{MastForest, MastNodeId, MerkleTreeNode},
+    mast::{MastForest, MastNodeId},
     Decorator, DecoratorList, Kernel, Operation, Program,
 };
 

assembly/src/assembler/procedure.rs

@@ -5,7 +5,7 @@ use crate::{
     diagnostics::SourceFile,
     LibraryPath, RpoDigest, SourceSpan, Spanned,
 };
-use vm_core::mast::{MastForest, MastNodeId, MerkleTreeNode};
+use vm_core::mast::{MastForest, MastNodeId};
 
 pub type CallSet = BTreeSet<RpoDigest>;
 

core/src/mast/mod.rs

@@ -5,33 +5,30 @@ use miden_crypto::hash::rpo::RpoDigest;
 
 mod node;
 pub use node::{
-    get_span_op_group_count, BasicBlockNode, CallNode, DynNode, ExternalNode, JoinNode, LoopNode,
-    MastNode, OpBatch, OperationOrDecorator, SplitNode, OP_BATCH_SIZE, OP_GROUP_SIZE,
+    BasicBlockNode, CallNode, DynNode, ExternalNode, JoinNode, LoopNode, MastNode, OpBatch,
+    OperationOrDecorator, SplitNode, OP_BATCH_SIZE, OP_GROUP_SIZE,
 };
-use winter_utils::{ByteReader, ByteWriter, Deserializable, DeserializationError, Serializable};
+use winter_utils::DeserializationError;
 
 mod serialization;
 
 #[cfg(test)]
 mod tests;
 
-/// Encapsulates the behavior that a [`MastNode`] (and all its variants) is expected to have.
-pub trait MerkleTreeNode {
-    fn digest(&self) -> RpoDigest;
-    fn to_display<'a>(&'a self, mast_forest: &'a MastForest) -> impl fmt::Display + 'a;
-}
-
 // MAST FOREST
 // ================================================================================================
 
-/// Represents the types of errors that can occur when dealing with MAST forest.
-#[derive(Debug, thiserror::Error)]
-pub enum MastForestError {
-    #[error(
-        "invalid node count: MAST forest exceeds the maximum of {} nodes",
-        MastForest::MAX_NODES
-    )]
-    TooManyNodes,
+/// Represents one or more procedures, represented as a collection of [`MastNode`]s.
+///
+/// A [`MastForest`] does not have an entrypoint, and hence is not executable. A [`crate::Program`]
+/// can be built from a [`MastForest`] to specify an entrypoint.
+#[derive(Clone, Debug, Default, PartialEq, Eq)]
+pub struct MastForest {
+    /// All of the nodes local to the trees comprising the MAST forest.
+    nodes: Vec<MastNode>,
+
+    /// Roots of procedures defined within this MAST forest.
+    roots: Vec<MastNodeId>,
 }
 
 // ------------------------------------------------------------------------------------------------
@@ -155,38 +152,33 @@ impl MastNodeId {
     }
 }
 
-impl fmt::Display for MastNodeId {
-    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        write!(f, "MastNodeId({})", self.0)
+impl From<MastNodeId> for u32 {
+    fn from(value: MastNodeId) -> Self {
+        value.0
     }
 }
 
-impl Serializable for MastNodeId {
-    fn write_into<W: ByteWriter>(&self, target: &mut W) {
-        self.0.write_into(target)
+impl From<&MastNodeId> for u32 {
+    fn from(value: &MastNodeId) -> Self {
+        value.0
     }
 }
 
-impl Deserializable for MastNodeId {
-    fn read_from<R: ByteReader>(source: &mut R) -> Result<Self, DeserializationError> {
-        let inner = source.read_u32()?;
-
-        Ok(Self(inner))
+impl fmt::Display for MastNodeId {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        write!(f, "MastNodeId({})", self.0)
     }
 }
 
 // MAST FOREST ERROR
 // ================================================================================================
 
-/// Represents one or more procedures, represented as a collection of [`MastNode`]s.
-///
-/// A [`MastForest`] does not have an entrypoint, and hence is not executable. A [`crate::Program`]
-/// can be built from a [`MastForest`] to specify an entrypoint.
-#[derive(Clone, Debug, Default, PartialEq, Eq)]
-pub struct MastForest {
-    /// All of the nodes local to the trees comprising the MAST forest.
-    nodes: Vec<MastNode>,
-
-    /// Roots of procedures defined within this MAST forest.
-    roots: Vec<MastNodeId>,
+/// Represents the types of errors that can occur when dealing with MAST forest.
+#[derive(Debug, thiserror::Error)]
+pub enum MastForestError {
+    #[error(
+        "invalid node count: MAST forest exceeds the maximum of {} nodes",
+        MastForest::MAX_NODES
+    )]
+    TooManyNodes,
 }