fix: split SkeletonNode into CurrentSkeletonNode and UpdatedSkeletonNode

crates/committer/src/patricia_merkle_tree.rs

@@ -1,6 +1,8 @@
+pub mod current_skeleton_node;
+pub mod current_skeleton_tree;
 pub mod errors;
 pub mod filled_node;
 pub mod filled_tree;
-pub mod skeleton_node;
-pub mod skeleton_tree;
 pub mod types;
+pub mod updated_skeleton_node;
+pub mod updated_skeleton_tree;

crates/committer/src/patricia_merkle_tree/current_skeleton_node.rs

@@ -0,0 +1,15 @@
+use crate::hash::types::HashOutput;
+use crate::patricia_merkle_tree::types::{EdgeData, LeafDataTrait, PathToBottom};
+
+#[allow(dead_code)]
+/// A node in the structure of a Patricia-Merkle tree, before the update.
+pub(crate) enum CurrentSkeletonNode<L: LeafDataTrait> {
+    Binary,
+    Edge { path_to_bottom: PathToBottom },
+    // Unmodified leaf / binary nodes on the merkle paths of modified leaves.
+    LeafOrBinarySibling(HashOutput),
+    // Unmodified edge nodes on the merkle paths of modified leaves.
+    EdgeSibling(EdgeData),
+    Leaf(L),
+    Empty,
+}

crates/committer/src/patricia_merkle_tree/current_skeleton_tree.rs

@@ -0,0 +1,19 @@
+use std::collections::HashMap;
+
+use crate::hash::types::HashFunction;
+use crate::patricia_merkle_tree::errors::SkeletonTreeError;
+use crate::patricia_merkle_tree::types::{LeafDataTrait, NodeIndex, TreeHashFunction};
+use crate::patricia_merkle_tree::updated_skeleton_tree::UpdatedSkeletonTree;
+
+/// Consider a Patricia-Merkle Tree which should be updated with new leaves.
+/// This trait represents the structure of the subtree which will be modified in the
+/// update. It also contains the hashes (for edge siblings - also the edge data) of the Sibling
+/// nodes on the Merkle paths from the updated leaves to the root.
+pub(crate) trait CurrentSkeletonTree<L: LeafDataTrait, H: HashFunction, TH: TreeHashFunction<L, H>>
+{
+    /// Computes and returns updated skeleton tree.
+    fn compute_updated_skeleton_tree(
+        &self,
+        index_to_updated_leaf: HashMap<NodeIndex, L>,
+    ) -> Result<impl UpdatedSkeletonTree<L, H, TH>, SkeletonTreeError>;
+}

crates/committer/src/patricia_merkle_tree/filled_node.rs

@@ -1,4 +1,4 @@
-use crate::patricia_merkle_tree::types::{LeafDataTrait, PathToBottom};
+use crate::patricia_merkle_tree::types::{EdgeData, LeafDataTrait};
 use crate::{hash::types::HashOutput, types::Felt};
 // TODO(Nimrod, 1/6/2024): Swap to starknet-types-core types once implemented.
 #[allow(dead_code)]
@@ -27,12 +27,6 @@ pub(crate) struct BinaryData {
     right_hash: HashOutput,
 }
 
-#[allow(dead_code)]
-pub(crate) struct EdgeData {
-    bottom_hash: HashOutput,
-    path_to_bottom: PathToBottom,
-}
-
 #[allow(dead_code)]
 pub(crate) enum LeafData {
     StorageValue(Felt),

crates/committer/src/patricia_merkle_tree/types.rs

@@ -23,6 +23,12 @@ pub(crate) struct PathToBottom {
     pub length: EdgePathLength,
 }
 
+#[allow(dead_code)]
+pub(crate) struct EdgeData {
+    bottom_hash: HashOutput,
+    path_to_bottom: PathToBottom,
+}
+
 pub(crate) trait LeafDataTrait {
     /// Returns true if leaf is empty.
     fn is_empty(&self) -> bool;

crates/committer/src/patricia_merkle_tree/updated_skeleton_node.rs

@@ -0,0 +1,12 @@
+use crate::hash::types::HashOutput;
+use crate::patricia_merkle_tree::types::{LeafDataTrait, PathToBottom};
+
+#[allow(dead_code)]
+/// A node in the structure of a Patricia-Merkle tree, after the update.
+pub(crate) enum UpdatedSkeletonNode<L: LeafDataTrait> {
+    Binary,
+    Edge { path_to_bottom: PathToBottom },
+    // All unmodified nodes on the merkle paths of modified leaves.
+    Sibling(HashOutput),
+    Leaf(L),
+}

crates/committer/src/patricia_merkle_tree/updated_skeleton_tree.rs

@@ -0,0 +1,14 @@
+use crate::hash::types::HashFunction;
+use crate::patricia_merkle_tree::errors::SkeletonTreeError;
+use crate::patricia_merkle_tree::filled_tree::FilledTree;
+use crate::patricia_merkle_tree::types::{LeafDataTrait, TreeHashFunction};
+
+/// Consider a Patricia-Merkle Tree which has been updated with new leaves.
+/// This trait represents the structure of the subtree which was modified in the update.
+/// It also contains the hashes of the Sibling nodes on the Merkle paths from the updated leaves
+/// to the root.
+pub(crate) trait UpdatedSkeletonTree<L: LeafDataTrait, H: HashFunction, TH: TreeHashFunction<L, H>>
+{
+    /// Computes and returns the filled tree.
+    fn compute_filled_tree(&self) -> Result<impl FilledTree<L>, SkeletonTreeError>;
+}