From 1ec49980ec876ef9395a9ae088f82d86a1a0d9f6 Mon Sep 17 00:00:00 2001
From: Alex Auvolat <alex@adnab.me>
Date: Thu, 11 Mar 2021 19:30:24 +0100
Subject: [PATCH] whoops

---
 src/table/merkle.rs |  3 ++-
 src/table/sync.rs   | 10 +++++++++-
 2 files changed, 11 insertions(+), 2 deletions(-)

diff --git a/src/table/merkle.rs b/src/table/merkle.rs
index 92c18e09..467ce615 100644
--- a/src/table/merkle.rs
+++ b/src/table/merkle.rs
@@ -50,7 +50,7 @@ pub(crate) struct MerkleUpdater {
 	empty_node_hash: Hash,
 }
 
-#[derive(Clone, Serialize, Deserialize)]
+#[derive(Clone, Debug, Serialize, Deserialize)]
 pub struct MerkleNodeKey {
 	// partition: first 16 bits (two bytes) of the partition_key's hash
 	pub partition: MerklePartition,
@@ -283,6 +283,7 @@ impl MerkleUpdater {
 		k: &MerkleNodeKey,
 		v: &MerkleNode,
 	) -> ConflictableTransactionResult<Hash, Error> {
+		trace!("Put Merkle node: {:?} => {:?}", k, v);
 		if *v == MerkleNode::Empty {
 			tx.remove(k.encode())?;
 			Ok(self.empty_node_hash)
diff --git a/src/table/sync.rs b/src/table/sync.rs
index f8ebb2f0..07d48155 100644
--- a/src/table/sync.rs
+++ b/src/table/sync.rs
@@ -370,6 +370,14 @@ where
 		must_exit: watch::Receiver<bool>,
 	) -> Result<(), Error> {
 		let root_ck = self.get_root_ck(partition.range)?;
+		if root_ck.is_empty() {
+			debug!(
+				"({}) Sync {:?} with {:?}: partition is empty.",
+				self.data.name, partition, who
+			);
+			return Ok(())
+		}
+
 		let root_ck_hash = hash_of(&root_ck)?;
 
 		// If their root checksum has level > than us, use that as a reference
@@ -637,7 +645,7 @@ fn join_ordered<'a, K: Ord + Eq, V1, V2>(
 			ret.push((&x[i].0, Some(&x[i].1), None));
 			i += 1;
 		} else if j < y.len() && (i == x.len() || x[i].0 > y[j].0) {
-			ret.push((&x[i].0, None, Some(&y[j].1)));
+			ret.push((&y[j].0, None, Some(&y[j].1)));
 			j += 1;
 		} else {
 			unreachable!();