3 files changed, 23 insertions, 7 deletions
diff --git a/src/merkle/merkletree.rs b/src/merkle/merkletree.rs
index f719ea5..812e300 100644
--- a/src/merkle/merkletree.rs
+++ b/src/merkle/merkletree.rs
@@ -52,6 +52,10 @@ impl MerkleTree {
         self.height
     }
 
+    pub fn is_empty(&self) -> bool {
+        self.len() == 0
+    }
+
     pub fn len(&self) -> usize {
         self.leaves.len()
     }
diff --git a/src/merkle/mod.rs b/src/merkle/mod.rs
index 48f87bc..1fea22f 100644
--- a/src/merkle/mod.rs
+++ b/src/merkle/mod.rs
@@ -1,13 +1,24 @@
-mod merkletree;
-mod node;
+pub mod merkletree;
+pub mod node;
 
-#[cfg(all(test, feature = "sha256"))]
+#[cfg(test)]
 mod tests {
-    use crate::hasher::SHA256Hasher;
+    use crate::hasher::*;
 
     use super::*;
 
     #[test]
+    fn test_merkle_tree_with_default_hasher() {
+        let data = vec!["a", "b", "c", "d"];
+        let tree = merkletree::MerkleTree::new(&DefaultHasher, data);
+
+        assert_eq!(tree.height(), 3);
+
+        assert_eq!(tree.root().hash(), "0xc0ff3");
+    }
+
+    #[test]
+    #[cfg(feature = "sha256")]
     fn test_merkle_tree_hashing() {
         let data = vec!["a", "b", "c", "d"];
         let tree = merkletree::MerkleTree::new(&SHA256Hasher, data);
@@ -21,6 +32,7 @@ mod tests {
     }
 
     #[test]
+    #[cfg(feature = "sha256")]
     fn test_merkle_tree_single_leaf() {
         let data = vec!["hello"];
         let tree = merkletree::MerkleTree::new(&SHA256Hasher, data);
diff --git a/src/merkle/node.rs b/src/merkle/node.rs
index 9d552cd..19cf8d4 100644
--- a/src/merkle/node.rs
+++ b/src/merkle/node.rs
@@ -1,20 +1,20 @@
 use crate::hasher::Hasher;
 
 #[derive(Debug, Clone)]
-enum NodeType {
+pub enum NodeType {
     Leaf,
     Internal(Box<Node>, Box<Node>),
 }
 
 impl NodeType {
-    pub fn left(&self) -> Option<&Box<Node>> {
+    pub fn left(&self) -> Option<&Node> {
         match self {
             NodeType::Leaf => None,
             NodeType::Internal(l, _) => Some(l),
         }
     }
 
-    pub fn right(&self) -> Option<&Box<Node>> {
+    pub fn right(&self) -> Option<&Node> {
         match self {
             NodeType::Leaf => None,
             NodeType::Internal(_, r) => Some(r),