refactor(client): small refactoring (#88)

* refactor(client): remove reference to reference

* refactor(client): remove unnecessary clone

* refactor(client): use some api instead of manual implementaion

Author: tottoto

src/client/legacy/client.rs

@@ -633,7 +633,7 @@ where
 impl<C: Clone, B> Clone for Client<C, B> {
     fn clone(&self) -> Client<C, B> {
         Client {
-            config: self.config.clone(),
+            config: self.config,
             exec: self.exec.clone(),
             #[cfg(feature = "http1")]
             h1_builder: self.h1_builder.clone(),
@@ -925,7 +925,7 @@ fn set_scheme(uri: &mut Uri, scheme: Scheme) {
         uri.scheme().is_none(),
         "set_scheme expects no existing scheme"
     );
-    let old = std::mem::replace(uri, Uri::default());
+    let old = std::mem::take(uri);
     let mut parts: ::http::uri::Parts = old.into();
     parts.scheme = Some(scheme);
     parts.path_and_query = Some("/".parse().expect("slash is a valid path"));

src/client/legacy/connect/http.rs

@@ -606,9 +606,7 @@ struct ConnectingTcpRemote {
 
 impl ConnectingTcpRemote {
     fn new(addrs: dns::SocketAddrs, connect_timeout: Option<Duration>) -> Self {
-        let connect_timeout = connect_timeout
-            .map(|t| t.checked_div(addrs.len() as u32))
-            .flatten();
+        let connect_timeout = connect_timeout.and_then(|t| t.checked_div(addrs.len() as u32));
 
         Self {
             addrs,

src/client/legacy/pool.rs

@@ -388,7 +388,7 @@ impl<T: Poolable, K: Key> PoolInner<T, K> {
             Some(value) => {
                 // borrow-check scope...
                 {
-                    let idle_list = self.idle.entry(key.clone()).or_insert_with(Vec::new);
+                    let idle_list = self.idle.entry(key.clone()).or_default();
                     if self.max_idle_per_host <= idle_list.len() {
                         trace!("max idle per host for {:?}, dropping connection", key);
                         return;

src/server/conn/auto.rs

@@ -411,9 +411,7 @@ pub struct Http1Builder<'a, E> {
 impl<E> Http1Builder<'_, E> {
     /// Http2 configuration.
     pub fn http2(&mut self) -> Http2Builder<'_, E> {
-        Http2Builder {
-            inner: &mut self.inner,
-        }
+        Http2Builder { inner: self.inner }
     }
 
     /// Set whether HTTP/1 connections should support half-closures.
@@ -546,9 +544,7 @@ pub struct Http2Builder<'a, E> {
 impl<E> Http2Builder<'_, E> {
     /// Http1 configuration.
     pub fn http1(&mut self) -> Http1Builder<'_, E> {
-        Http1Builder {
-            inner: &mut self.inner,
-        }
+        Http1Builder { inner: self.inner }
     }
 
     /// Sets the [`SETTINGS_INITIAL_WINDOW_SIZE`][spec] option for HTTP2