Refactor some types in rpc/client

Signed-off-by: Nick Cameron <nrc@ncameron.org>

src/rpc/client.rs

@@ -4,9 +4,8 @@
 #![allow(dead_code)]
 
 use std::{
-    collections::HashMap,
+    collections::hash_map::{self, HashMap},
     fmt,
-    ops::Deref,
     sync::{Arc, RwLock},
     time::Duration,
 };
@@ -108,7 +107,7 @@ impl RpcClientInner {
     }
 
     fn locate_key(&self, key: &Key) -> impl Future<Output = Result<KeyLocation>> {
-        self.load_region(key).map_ok(KeyLocation::new)
+        self.load_region(key)
     }
 
     fn kv_client(&self, context: RegionContext) -> Result<(RegionContext, Arc<KvClient>)> {
@@ -197,7 +196,7 @@ impl RpcClient {
                 let peer = location.peer().expect("leader must exist");
                 let store_id = peer.get_store_id();
                 inner.load_store(store_id).map_ok(|store| RegionContext {
-                    region: location.into_inner(),
+                    region: location,
                     store,
                 })
             })
@@ -257,7 +256,6 @@ impl RpcClient {
         let inner = self.inner();
         self.group_tasks_by_region(keys)
             .and_then(move |task_groups| {
-                let task_groups = task_groups.into_inner();
                 let mut tasks = Vec::with_capacity(task_groups.len());
                 for (region, keys) in task_groups.into_iter() {
                     let inner = Arc::clone(&inner);
@@ -302,7 +300,6 @@ impl RpcClient {
             Either::Right(
                 self.group_tasks_by_region(pairs)
                     .and_then(move |task_groups| {
-                        let task_groups = task_groups.into_inner();
                         let mut tasks = Vec::with_capacity(task_groups.len());
                         for (region, pairs) in task_groups.into_iter() {
                             let inner = Arc::clone(&inner);
@@ -336,7 +333,6 @@ impl RpcClient {
         let inner = self.inner();
         self.group_tasks_by_region(keys)
             .and_then(move |task_groups| {
-                let task_groups = task_groups.into_inner();
                 let mut tasks = Vec::with_capacity(task_groups.len());
                 for (region, keys) in task_groups.into_iter() {
                     let inner = Arc::clone(&inner);
@@ -374,8 +370,8 @@ impl RpcClient {
         let inner = Arc::clone(&self.inner);
         loop_fn((inner, scan), |(inner, scan)| {
             inner.locate_key(scan.start_key()).and_then(|location| {
-                let region = location.into_inner();
-                let cf = scan.cf.clone();
+                let region = location;
+                let cf = scan.state.cf.clone();
                 Self::region_context_by_id(Arc::clone(&inner), region.id)
                     .map_ok(|(region, client)| {
                         (scan, region.range(), RawContext::new(region, client, cf))
@@ -384,11 +380,17 @@ impl RpcClient {
                         let (start_key, end_key) = scan.range();
                         context
                             .client()
-                            .raw_scan(context, start_key, end_key, scan.limit, scan.key_only)
+                            .raw_scan(
+                                context,
+                                start_key,
+                                end_key,
+                                scan.state.limit,
+                                scan.state.key_only,
+                            )
                             .map_ok(|pairs| (scan, region_range, pairs))
                     })
                     .map_ok(|(mut scan, region_range, mut pairs)| {
-                        let limit = scan.limit;
+                        let limit = scan.state.limit;
                         scan.result_mut().append(&mut pairs);
                         if scan.result().len() as u32 >= limit {
                             Loop::Break(scan.into_inner())
@@ -424,8 +426,8 @@ impl RpcClient {
         let inner = Arc::clone(&self.inner);
         loop_fn((inner, scan), |(inner, scan)| {
             inner.locate_key(scan.start_key()).and_then(|location| {
-                let region = location.into_inner();
-                let cf = scan.clone();
+                let region = location;
+                let cf = scan.state.clone();
                 Self::region_context_by_id(Arc::clone(&inner), region.id)
                     .map_ok(|(region, client)| {
                         (scan, region.range(), RawContext::new(region, client, cf))
@@ -523,25 +525,7 @@ impl TxnContext {
     }
 }
 
-struct KeyLocation(Region);
-
-impl KeyLocation {
-    fn new(region: Region) -> Self {
-        KeyLocation(region)
-    }
-
-    fn into_inner(self) -> Region {
-        self.0
-    }
-}
-
-impl Deref for KeyLocation {
-    type Target = Region;
-
-    fn deref(&self) -> &Self::Target {
-        &self.0
-    }
-}
+type KeyLocation = Region;
 
 trait GroupingTask: Clone + Default + Sized {
     fn key(&self) -> &Key;
@@ -550,16 +534,14 @@ trait GroupingTask: Clone + Default + Sized {
 #[derive(Default)]
 struct GroupedTasks<Task: GroupingTask>(HashMap<RegionVerId, Vec<Task>>, RegionVerId);
 
-impl<Task> GroupedTasks<Task>
-where
-    Task: GroupingTask,
-{
+impl<Task: GroupingTask> GroupedTasks<Task> {
     fn new(ver_id: RegionVerId, task: Task) -> Self {
         let mut map = HashMap::with_capacity(1);
         map.insert(ver_id.clone(), vec![task]);
         GroupedTasks(map, ver_id)
     }
 
+    #[inline]
     fn add(&mut self, ver_id: RegionVerId, task: Task) {
         self.0
             .entry(ver_id)
@@ -567,19 +549,18 @@ where
             .push(task)
     }
 
-    fn into_inner(self) -> HashMap<RegionVerId, Vec<Task>> {
-        self.0
+    #[inline]
+    fn len(&self) -> usize {
+        self.0.len()
     }
 }
 
-impl<Task> Deref for GroupedTasks<Task>
-where
-    Task: GroupingTask,
-{
-    type Target = HashMap<RegionVerId, Vec<Task>>;
+impl<Task: GroupingTask> IntoIterator for GroupedTasks<Task> {
+    type Item = (RegionVerId, Vec<Task>);
+    type IntoIter = hash_map::IntoIter<RegionVerId, Vec<Task>>;
 
-    fn deref(&self) -> &Self::Target {
-        &self.0
+    fn into_iter(self) -> hash_map::IntoIter<RegionVerId, Vec<Task>> {
+        self.0.into_iter()
     }
 }
 
@@ -666,15 +647,3 @@ where
         &self.result
     }
 }
-
-impl<Res, State> Deref for ScanRegionsContext<Res, State>
-where
-    Res: Default,
-    State: Sized,
-{
-    type Target = State;
-
-    fn deref(&self) -> &Self::Target {
-        &self.state
-    }
-}