table: fix insert_many to not send duplicates

src/table/table.rs

@@ -196,6 +196,8 @@ impl<F: TableSchema, R: TableReplication> Table<F, R> {
 			let hash = entry.partition_key().hash();
 			let mut write_sets = self.data.replication.write_sets(&hash);
 			for set in write_sets.as_mut().iter_mut() {
+				// Sort nodes in each write sets to merge write sets with same
+				// nodes but in possibly different orders
 				set.sort();
 			}
 			let e_enc = Arc::new(ByteBuf::from(entry.encode()?));
@@ -220,7 +222,16 @@ impl<F: TableSchema, R: TableReplication> Table<F, R> {
 		for (write_sets, entry_enc) in entries_vec.iter() {
 			for write_set in write_sets.as_ref().iter() {
 				for node in write_set.iter() {
-					call_list.entry(*node).or_default().push(entry_enc.clone())
+					let node_entries = call_list.entry(*node).or_default();
+					match node_entries.last() {
+						Some(x) if Arc::ptr_eq(x, entry_enc) => {
+							// skip if entry already in list to send to this node
+							// (could happen if node is in several write sets for this entry)
+						}
+						_ => {
+							node_entries.push(entry_enc.clone());
+						}
+					}
 				}
 			}
 		}