src/table/crdt/crdt.rs

@@ -52,10 +52,8 @@ where
 				*self = other.clone();
 			}
 			warn!("Making an arbitrary choice: {:?}", self);
-		} else {
-			if other > self {
-				*self = other.clone();
-			}
+		} else if other > self {
+			*self = other.clone();
 		}
 	}
 }

src/table/crdt/lww_map.rs

@@ -94,7 +94,7 @@ where
 	/// put_my_crdt_value(a);
 	/// ```
 	pub fn take_and_clear(&mut self) -> Self {
-		let vals = std::mem::replace(&mut self.vals, vec![]);
+		let vals = std::mem::take(&mut self.vals);
 		Self { vals }
 	}
 	/// Removes all values from the map
@@ -113,10 +113,16 @@ where
 	pub fn items(&self) -> &[(K, u64, V)] {
 		&self.vals[..]
 	}
+
 	/// Returns the number of items in the map
 	pub fn len(&self) -> usize {
 		self.vals.len()
 	}
+
+	/// Returns true if the map is empty
+	pub fn is_empty(&self) -> bool {
+		self.len() == 0
+	}
 }
 
 impl<K, V> CRDT for LWWMap<K, V>
@@ -143,3 +149,13 @@ where
 		}
 	}
 }
+
+impl<K, V> Default for LWWMap<K, V>
+where
+	K: Ord,
+	V: CRDT,
+{
+	fn default() -> Self {
+		Self::new()
+	}
+}

src/table/crdt/map.rs

@@ -62,6 +62,11 @@ where
 	pub fn len(&self) -> usize {
 		self.vals.len()
 	}
+
+	/// Returns true if the map is empty
+	pub fn is_empty(&self) -> bool {
+		self.len() == 0
+	}
 }
 
 impl<K, V> CRDT for Map<K, V>
@@ -82,3 +87,13 @@ where
 		}
 	}
 }
+
+impl<K, V> Default for Map<K, V>
+where
+	K: Clone + Ord,
+	V: Clone + CRDT,
+{
+	fn default() -> Self {
+		Self::new()
+	}
+}

src/table/crdt/mod.rs

@@ -10,6 +10,7 @@
 //! Learn more about CRDT [on Wikipedia](https://en.wikipedia.org/wiki/Conflict-free_replicated_data_type)
 
 mod bool;
+#[allow(clippy::module_inception)]
 mod crdt;
 mod lww;
 mod lww_map;

src/table/gc.rs

@@ -85,8 +85,8 @@ where
 				}
 			}
 			select! {
-				_ = tokio::time::sleep(Duration::from_secs(10)).fuse() => (),
-				_ = must_exit.changed().fuse() => (),
+				_ = tokio::time::sleep(Duration::from_secs(10)).fuse() => {},
+				_ = must_exit.changed().fuse() => {},
 			}
 		}
 	}
@@ -120,7 +120,7 @@ where
 			self.todo_remove_if_equal(&k[..], vhash)?;
 		}
 
-		if entries.len() == 0 {
+		if entries.is_empty() {
 			// Nothing to do in this iteration
 			return Ok(false);
 		}
@@ -247,7 +247,7 @@ where
 				}
 				Ok(GcRPC::Ok)
 			}
-			_ => Err(Error::Message(format!("Unexpected GC RPC"))),
+			_ => Err(Error::Message("Unexpected GC RPC".to_string())),
 		}
 	}
 }

src/table/lib.rs

@@ -1,4 +1,5 @@
 #![recursion_limit = "1024"]
+#![allow(clippy::comparison_chain, clippy::upper_case_acronyms)]
 
 #[macro_use]
 extern crate log;

src/table/merkle.rs

@@ -111,8 +111,8 @@ where
 				}
 			} else {
 				select! {
-					_ = self.data.merkle_todo_notify.notified().fuse() => (),
-					_ = must_exit.changed().fuse() => (),
+					_ = self.data.merkle_todo_notify.notified().fuse() => {},
+					_ = must_exit.changed().fuse() => {},
 				}
 			}
 		}
@@ -121,10 +121,10 @@ where
 	fn update_item(&self, k: &[u8], vhash_by: &[u8]) -> Result<(), Error> {
 		let khash = blake2sum(k);
 
-		let new_vhash = if vhash_by.len() == 0 {
+		let new_vhash = if vhash_by.is_empty() {
 			None
 		} else {
-			Some(Hash::try_from(&vhash_by[..]).unwrap())
+			Some(Hash::try_from(vhash_by).unwrap())
 		};
 
 		let key = MerkleNodeKey {
@@ -168,14 +168,7 @@ where
 		// This update is an Option<_>, so that it is None if the update is a no-op
 		// and we can thus skip recalculating and re-storing everything
 		let mutate = match self.read_node_txn(tx, &key)? {
-			MerkleNode::Empty => {
-				if let Some(vhv) = new_vhash {
-					Some(MerkleNode::Leaf(k.to_vec(), vhv))
-				} else {
-					// Nothing to do, keep empty node
-					None
-				}
-			}
+			MerkleNode::Empty => new_vhash.map(|vhv| MerkleNode::Leaf(k.to_vec(), vhv)),
 			MerkleNode::Intermediate(mut children) => {
 				let key2 = key.next_key(khash);
 				if let Some(subhash) = self.update_item_rec(tx, k, khash, &key2, new_vhash)? {
@@ -186,7 +179,7 @@ where
 						intermediate_set_child(&mut children, key2.prefix[i], subhash);
 					}
 
-					if children.len() == 0 {
+					if children.is_empty() {
 						// should not happen
 						warn!(
 							"({}) Replacing intermediate node with empty node, should not happen.",

src/table/schema.rs

@@ -18,7 +18,7 @@ impl PartitionKey for String {
 
 impl PartitionKey for Hash {
 	fn hash(&self) -> Hash {
-		self.clone()
+		*self
 	}
 }
 

src/table/sync.rs

@@ -150,14 +150,12 @@ where
 					if let Some(busy) = busy_opt {
 						if busy {
 							nothing_to_do_since = None;
-						} else {
-							if nothing_to_do_since.is_none() {
-								nothing_to_do_since = Some(Instant::now());
-							}
+						} else if nothing_to_do_since.is_none() {
+							nothing_to_do_since = Some(Instant::now());
 						}
 					}
 				}
-				_ = must_exit.changed().fuse() => (),
+				_ = must_exit.changed().fuse() => {},
 				_ = tokio::time::sleep(Duration::from_secs(1)).fuse() => {
 					if nothing_to_do_since.map(|t| Instant::now() - t >= ANTI_ENTROPY_INTERVAL).unwrap_or(false) {
 						nothing_to_do_since = None;
@@ -277,7 +275,7 @@ where
 				}
 			}
 
-			if items.len() > 0 {
+			if !items.is_empty() {
 				let nodes = self
 					.data
 					.replication
@@ -292,9 +290,10 @@ where
 					break;
 				}
 				if nodes.len() < self.data.replication.write_quorum() {
-					return Err(Error::Message(format!(
+					return Err(Error::Message(
 						"Not offloading as we don't have a quorum of nodes to write to."
-					)));
+							.to_string(),
+					));
 				}
 
 				counter += 1;
@@ -317,14 +316,14 @@ where
 
 	async fn offload_items(
 		self: &Arc<Self>,
-		items: &Vec<(Vec<u8>, Arc<ByteBuf>)>,
+		items: &[(Vec<u8>, Arc<ByteBuf>)],
 		nodes: &[UUID],
 	) -> Result<(), Error> {
 		let values = items.iter().map(|(_k, v)| v.clone()).collect::<Vec<_>>();
 
 		self.rpc_client
 			.try_call_many(
-				&nodes[..],
+				nodes,
 				SyncRPC::Items(values),
 				RequestStrategy::with_quorum(nodes.len()).with_timeout(TABLE_SYNC_RPC_TIMEOUT),
 			)
@@ -467,7 +466,7 @@ where
 			}
 
 			if todo_items.len() >= 256 {
-				self.send_items(who, std::mem::replace(&mut todo_items, vec![]))
+				self.send_items(who, std::mem::take(&mut todo_items))
 					.await?;
 			}
 		}
@@ -523,7 +522,7 @@ where
 				self.data.update_many(items)?;
 				Ok(SyncRPC::Ok)
 			}
-			_ => Err(Error::Message(format!("Unexpected sync RPC"))),
+			_ => Err(Error::Message("Unexpected sync RPC".to_string())),
 		}
 	}
 }

src/table/table.rs

@@ -109,17 +109,14 @@ where
 	}
 
 	pub async fn insert_many(&self, entries: &[F::E]) -> Result<(), Error> {
-		let mut call_list = HashMap::new();
+		let mut call_list: HashMap<_, Vec<_>> = HashMap::new();
 
 		for entry in entries.iter() {
 			let hash = entry.partition_key().hash();
 			let who = self.data.replication.write_nodes(&hash);
 			let e_enc = Arc::new(ByteBuf::from(rmp_to_vec_all_named(entry)?));
 			for node in who {
-				if !call_list.contains_key(&node) {
-					call_list.insert(node, vec![]);
-				}
-				call_list.get_mut(&node).unwrap().push(e_enc.clone());
+				call_list.entry(node).or_default().push(e_enc.clone());
 			}
 		}
 
@@ -183,7 +180,7 @@ where
 					}
 				}
 			} else {
-				return Err(Error::Message(format!("Invalid return value to read")));
+				return Err(Error::Message("Invalid return value to read".to_string()));
 			}
 		}
 		if let Some(ret_entry) = &ret {
@@ -268,7 +265,7 @@ where
 		let what_enc = Arc::new(ByteBuf::from(rmp_to_vec_all_named(&what)?));
 		self.rpc_client
 			.try_call_many(
-				&who[..],
+				who,
 				TableRPC::<F>::Update(vec![what_enc]),
 				RequestStrategy::with_quorum(who.len()).with_timeout(TABLE_RPC_TIMEOUT),
 			)
@@ -307,7 +304,7 @@ where
 				self.data.update_many(pairs)?;
 				Ok(TableRPC::Ok)
 			}
-			_ => Err(Error::BadRPC(format!("Unexpected table RPC"))),
+			_ => Err(Error::BadRPC("Unexpected table RPC".to_string())),
 		}
 	}
 }