starknet_committer: add index layout subtree

crates/starknet_committer/src/db/index_db/mod.rs

@@ -1,3 +1,4 @@
 pub mod leaves;
 #[cfg(test)]
 pub mod leaves_test;
+pub mod types;

crates/starknet_committer/src/db/index_db/types.rs

@@ -0,0 +1,60 @@
+use starknet_patricia::patricia_merkle_tree::filled_tree::node::FilledNode;
+use starknet_patricia::patricia_merkle_tree::node_data::leaf::Leaf;
+use starknet_patricia::patricia_merkle_tree::traversal::{SubTreeTrait, UnmodifiedChildTraversal};
+use starknet_patricia::patricia_merkle_tree::types::{NodeIndex, SortedLeafIndices};
+use starknet_patricia_storage::db_object::HasStaticPrefix;
+use starknet_patricia_storage::storage_trait::DbKeyPrefix;
+
+pub struct IndexFilledNode<L: Leaf>(pub FilledNode<L, ()>);
+
+pub struct IndexNodeContext {
+    pub is_leaf: bool,
+}
+
+pub struct IndexLayoutSubTree<'a> {
+    pub sorted_leaf_indices: SortedLeafIndices<'a>,
+    pub root_index: NodeIndex,
+}
+
+impl<'a> SubTreeTrait<'a> for IndexLayoutSubTree<'a> {
+    type NodeData = ();
+    type NodeDeserializeContext = IndexNodeContext;
+
+    fn create(
+        sorted_leaf_indices: SortedLeafIndices<'a>,
+        root_index: NodeIndex,
+        _child_data: Self::NodeData,
+    ) -> Self {
+        Self { sorted_leaf_indices, root_index }
+    }
+
+    fn get_root_index(&self) -> NodeIndex {
+        self.root_index
+    }
+
+    fn get_sorted_leaf_indices(&self) -> &SortedLeafIndices<'a> {
+        &self.sorted_leaf_indices
+    }
+
+    fn should_traverse_unmodified_child(_data: Self::NodeData) -> UnmodifiedChildTraversal {
+        // In index layout, to obtain a child hash for an `OriginalSkeletonNode`, we need to read
+        // the child from the DB (this is not true in facts layout, where a node stores its children
+        // hashes).
+        UnmodifiedChildTraversal::Traverse
+    }
+
+    fn get_root_context(&self) -> Self::NodeDeserializeContext {
+        Self::NodeDeserializeContext { is_leaf: self.is_leaf() }
+    }
+
+    fn get_root_prefix<L: Leaf>(
+        &self,
+        key_context: &<L as HasStaticPrefix>::KeyContext,
+    ) -> DbKeyPrefix {
+        L::get_static_prefix(key_context)
+    }
+
+    fn get_root_suffix(&self) -> Vec<u8> {
+        self.root_index.0.to_be_bytes().to_vec()
+    }
+}