Address feedback again

node/primitives/src/lib.rs

@@ -55,6 +55,11 @@ pub use disputes::{
 // For a 16-ary Merkle Prefix Trie, we can expect at most 16 32-byte hashes per node.
 const MERKLE_NODE_MAX_SIZE: usize = 512;
 // 16-ary Merkle Prefix Trie for 32-bit ValidatorIndex has depth at most 8.
+// Merkle Prefix Tries use the key in order to determine Proof structure.
+// To that effect, at every depth we require 4-bit nibbles from the key in
+// order to determine the Trie node of that key.
+// In this case, the key is a 32-bit validator index, and 32/4 = 8, the max
+// proof depth.
 const MERKLE_PROOF_MAX_DEPTH: usize = 8;
 
 /// The bomb limit for decompressing code blobs.
@@ -305,7 +310,7 @@ impl Proof {
 }
 
 #[derive(thiserror::Error, Debug)]
-///
+/// This is a convenience error type to adequately handle erronious Merkle Proofs
 pub enum MerkleProofError {
 	#[error("Merkle max proof depth exceeded {0} > {} .", MERKLE_PROOF_MAX_DEPTH)]
 	/// This error signifies that the Proof length exceeds the trie's max depth
@@ -330,7 +335,7 @@ impl TryFrom<Vec<Vec<u8>>> for Proof {
 				.map_err(|_| Self::Error::MerkleProofNodeSizeExceeded(length))?;
 			out.push(data);
 		}
-		Ok(Proof(BoundedVec::from_vec(out).expect("Buffer size is deterined above. qed")))
+		Ok(Proof(BoundedVec::from_vec(out).expect("Buffer size is determined above. qed")))
 	}
 }