feature: add conditional support for serde

src/merkle/delta.rs

@@ -13,6 +13,7 @@ use super::{empty_roots::EMPTY_WORD, Felt, SimpleSmt};
 /// [RpoDigest] represents the root of the Merkle tree and [MerkleTreeDelta] represents the
 /// differences between the initial and final Merkle tree states.
 #[derive(Default, Debug, Clone, PartialEq, Eq)]
+#[cfg_attr(feature = "serde", derive(serde::Deserialize, serde::Serialize))]
 pub struct MerkleStoreDelta(pub Vec<(RpoDigest, MerkleTreeDelta)>);
 
 // MERKLE TREE DELTA
@@ -26,6 +27,7 @@ pub struct MerkleStoreDelta(pub Vec<(RpoDigest, MerkleTreeDelta)>);
 /// - updated_slots: index-value pairs of slots where values were set to non [ZERO; 4] values.
 #[cfg(not(test))]
 #[derive(Debug, Clone, PartialEq, Eq)]
+#[cfg_attr(feature = "serde", derive(serde::Deserialize, serde::Serialize))]
 pub struct MerkleTreeDelta {
     depth: u8,
     cleared_slots: Vec<u64>,
@@ -107,6 +109,7 @@ pub fn merkle_tree_delta<T: KvMap<RpoDigest, StoreNode>>(
 // --------------------------------------------------------------------------------------------
 #[cfg(test)]
 #[derive(Debug, Clone, PartialEq, Eq)]
+#[cfg_attr(feature = "serde", derive(serde::Deserialize, serde::Serialize))]
 pub struct MerkleTreeDelta {
     pub depth: u8,
     pub cleared_slots: Vec<u64>,

src/merkle/index.rs

@@ -21,6 +21,7 @@ use core::fmt::Display;
 /// The root is represented by the pair $(0, 0)$, its left child is $(1, 0)$ and its right child
 /// $(1, 1)$.
 #[derive(Debug, Default, Copy, Clone, Eq, PartialEq, PartialOrd, Ord, Hash)]
+#[cfg_attr(feature = "serde", derive(serde::Deserialize, serde::Serialize))]
 pub struct NodeIndex {
     depth: u8,
     value: u64,

src/merkle/merkle_tree.rs

@@ -8,6 +8,7 @@ use winter_math::log2;
 
 /// A fully-balanced binary Merkle tree (i.e., a tree where the number of leaves is a power of two).
 #[derive(Debug, Clone, PartialEq, Eq)]
+#[cfg_attr(feature = "serde", derive(serde::Deserialize, serde::Serialize))]
 pub struct MerkleTree {
     nodes: Vec<RpoDigest>,
 }

src/merkle/mmr/accumulator.rs

@@ -4,6 +4,7 @@ use super::{
 };
 
 #[derive(Debug, Clone, PartialEq)]
+#[cfg_attr(feature = "serde", derive(serde::Deserialize, serde::Serialize))]
 pub struct MmrPeaks {
     /// The number of leaves is used to differentiate accumulators that have the same number of
     /// peaks. This happens because the number of peaks goes up-and-down as the structure is used

src/merkle/mmr/full.rs

@@ -29,6 +29,7 @@ use std::error::Error;
 /// Since this is a full representation of the MMR, elements are never removed and the MMR will
 /// grow roughly `O(2n)` in number of leaf elements.
 #[derive(Debug, Clone)]
+#[cfg_attr(feature = "serde", derive(serde::Deserialize, serde::Serialize))]
 pub struct Mmr {
     /// Refer to the `forest` method documentation for details of the semantics of this value.
     pub(super) forest: usize,

src/merkle/mmr/proof.rs

@@ -3,6 +3,7 @@ use super::super::MerklePath;
 use super::full::{high_bitmask, leaf_to_corresponding_tree};
 
 #[derive(Debug, Clone, PartialEq)]
+#[cfg_attr(feature = "serde", derive(serde::Deserialize, serde::Serialize))]
 pub struct MmrProof {
     /// The state of the MMR when the MmrProof was created.
     pub forest: usize,

src/merkle/node.rs

@@ -2,6 +2,7 @@ use crate::hash::rpo::RpoDigest;
 
 /// Representation of a node with two children used for iterating over containers.
 #[derive(Debug, Clone, PartialEq, Eq)]
+#[cfg_attr(feature = "serde", derive(serde::Deserialize, serde::Serialize))]
 pub struct InnerNodeInfo {
     pub value: RpoDigest,
     pub left: RpoDigest,

src/merkle/partial_mt/mod.rs

@@ -28,6 +28,7 @@ const EMPTY_DIGEST: RpoDigest = RpoDigest::new([ZERO; 4]);
 ///
 /// The root of the tree is recomputed on each new leaf update.
 #[derive(Debug, Clone, PartialEq, Eq)]
+#[cfg_attr(feature = "serde", derive(serde::Deserialize, serde::Serialize))]
 pub struct PartialMerkleTree {
     max_depth: u8,
     nodes: BTreeMap<NodeIndex, RpoDigest>,

src/merkle/path.rs

@@ -6,6 +6,7 @@ use core::ops::{Deref, DerefMut};
 
 /// A merkle path container, composed of a sequence of nodes of a Merkle tree.
 #[derive(Clone, Debug, Default, PartialEq, Eq)]
+#[cfg_attr(feature = "serde", derive(serde::Deserialize, serde::Serialize))]
 pub struct MerklePath {
     nodes: Vec<RpoDigest>,
 }

src/merkle/simple_smt/mod.rs

@@ -13,6 +13,7 @@ mod tests;
 ///
 /// The root of the tree is recomputed on each new leaf update.
 #[derive(Debug, Clone, PartialEq, Eq)]
+#[cfg_attr(feature = "serde", derive(serde::Deserialize, serde::Serialize))]
 pub struct SimpleSmt {
     depth: u8,
     root: RpoDigest,
@@ -265,6 +266,7 @@ impl SimpleSmt {
 // ================================================================================================
 
 #[derive(Debug, Default, Clone, PartialEq, Eq)]
+#[cfg_attr(feature = "serde", derive(serde::Deserialize, serde::Serialize))]
 struct BranchNode {
     left: RpoDigest,
     right: RpoDigest,

src/merkle/store/mod.rs

@@ -19,6 +19,7 @@ pub type DefaultMerkleStore = MerkleStore<BTreeMap<RpoDigest, StoreNode>>;
 pub type RecordingMerkleStore = MerkleStore<RecordingMap<RpoDigest, StoreNode>>;
 
 #[derive(Debug, Default, Copy, Clone, Eq, PartialEq)]
+#[cfg_attr(feature = "serde", derive(serde::Deserialize, serde::Serialize))]
 pub struct StoreNode {
     left: RpoDigest,
     right: RpoDigest,
@@ -87,6 +88,7 @@ pub struct StoreNode {
 /// assert_eq!(store.num_internal_nodes() - 255, 10);
 /// ```
 #[derive(Debug, Clone, Eq, PartialEq)]
+#[cfg_attr(feature = "serde", derive(serde::Deserialize, serde::Serialize))]
 pub struct MerkleStore<T: KvMap<RpoDigest, StoreNode> = BTreeMap<RpoDigest, StoreNode>> {
     nodes: T,
 }

src/merkle/tiered_smt/mod.rs

@@ -43,6 +43,7 @@ mod tests;
 /// - Leaf node at depths 16, 32, or 64: hash(key, value, domain=depth).
 /// - Leaf node at depth 64: hash([key_0, value_0, ..., key_n, value_n], domain=64).
 #[derive(Debug, Clone, PartialEq, Eq)]
+#[cfg_attr(feature = "serde", derive(serde::Deserialize, serde::Serialize))]
 pub struct TieredSmt {
     root: RpoDigest,
     nodes: NodeStore,

src/merkle/tiered_smt/nodes.rs

@@ -24,6 +24,7 @@ const MAX_DEPTH: u8 = super::TieredSmt::MAX_DEPTH;
 /// represent leaf nodes in a Tiered Sparse Merkle tree. In the current implementation, [BTreeSet]s
 /// are used to determine the position of the leaves in the tree.
 #[derive(Debug, Clone, PartialEq, Eq)]
+#[cfg_attr(feature = "serde", derive(serde::Deserialize, serde::Serialize))]
 pub struct NodeStore {
     nodes: BTreeMap<NodeIndex, RpoDigest>,
     upper_leaves: BTreeSet<NodeIndex>,

src/merkle/tiered_smt/values.rs

@@ -26,6 +26,7 @@ const MAX_DEPTH: u8 = super::TieredSmt::MAX_DEPTH;
 /// The store supports lookup by the full key (i.e. [RpoDigest]) as well as by the 64-bit key
 /// prefix.
 #[derive(Debug, Default, Clone, PartialEq, Eq)]
+#[cfg_attr(feature = "serde", derive(serde::Deserialize, serde::Serialize))]
 pub struct ValueStore {
     values: BTreeMap<u64, StoreEntry>,
 }
@@ -173,6 +174,7 @@ impl ValueStore {
 /// An entry can contain either a single key-value pair or a vector of key-value pairs sorted by
 /// key.
 #[derive(Debug, Clone, PartialEq, Eq)]
+#[cfg_attr(feature = "serde", derive(serde::Deserialize, serde::Serialize))]
 pub enum StoreEntry {
     Single((RpoDigest, Word)),
     List(Vec<(RpoDigest, Word)>),