Remove useless clones (#609)

src/address/envelope.rs

@@ -116,11 +116,12 @@ impl TryFrom<&Headers> for Envelope {
             // ... else try From
             None => match headers.get::<header::From>() {
                 Some(header::From(a)) => {
-                    let from: Vec<Mailbox> = a.into();
+                    let mut from: Vec<Mailbox> = a.into();
                     if from.len() > 1 {
                         return Err(Error::TooManyFrom);
                     }
-                    Some(from[0].email.clone())
+                    let from = from.pop().expect("From header has 1 Mailbox");
+                    Some(from.email)
                 }
                 None => None,
             },
@@ -131,9 +132,7 @@ impl TryFrom<&Headers> for Envelope {
             mailboxes: Option<Mailboxes>,
         ) {
             if let Some(mailboxes) = mailboxes {
-                for mailbox in mailboxes.iter() {
-                    addresses.push(mailbox.email.clone());
-                }
+                addresses.extend(mailboxes.into_iter().map(|mb| mb.email));
             }
         }
         let mut to = vec![];

src/transport/smtp/client/async_net.rs

@@ -1,9 +1,3 @@
-#[cfg(any(
-    feature = "tokio02-rustls-tls",
-    feature = "tokio1-rustls-tls",
-    feature = "async-std1-rustls-tls"
-))]
-use std::sync::Arc;
 use std::{
     mem,
     net::SocketAddr,
@@ -303,7 +297,7 @@ impl AsyncNetworkStream {
                     let domain =
                         DNSNameRef::try_from_ascii_str(&domain).map_err(error::connection)?;
 
-                    let connector = TlsConnector::from(Arc::new(config));
+                    let connector = TlsConnector::from(config);
                     let stream = connector
                         .connect(domain, tcp_stream)
                         .await
@@ -352,7 +346,7 @@ impl AsyncNetworkStream {
                     let domain =
                         DNSNameRef::try_from_ascii_str(&domain).map_err(error::connection)?;
 
-                    let connector = TlsConnector::from(Arc::new(config));
+                    let connector = TlsConnector::from(config);
                     let stream = connector
                         .connect(domain, tcp_stream)
                         .await
@@ -404,7 +398,7 @@ impl AsyncNetworkStream {
                     let domain =
                         DNSNameRef::try_from_ascii_str(&domain).map_err(error::connection)?;
 
-                    let connector = TlsConnector::from(Arc::new(config));
+                    let connector = TlsConnector::from(config);
                     let stream = connector
                         .connect(domain, tcp_stream)
                         .await

src/transport/smtp/client/net.rs

@@ -1,5 +1,3 @@
-#[cfg(feature = "rustls-tls")]
-use std::sync::Arc;
 use std::{
     io::{self, Read, Write},
     mem,
@@ -155,10 +153,7 @@ impl NetworkStream {
 
                 let domain = DNSNameRef::try_from_ascii_str(tls_parameters.domain())
                     .map_err(error::connection)?;
-                let stream = StreamOwned::new(
-                    ClientSession::new(&Arc::new(connector.clone()), domain),
-                    tcp_stream,
-                );
+                let stream = StreamOwned::new(ClientSession::new(&connector, domain), tcp_stream);
 
                 InnerNetworkStream::RustlsTls(stream)
             }

src/transport/smtp/client/tls.rs

@@ -179,7 +179,7 @@ impl TlsParametersBuilder {
 
         tls.root_store.add_server_trust_anchors(&TLS_SERVER_ROOTS);
         Ok(TlsParameters {
-            connector: InnerTlsParameters::RustlsTls(tls),
+            connector: InnerTlsParameters::RustlsTls(Arc::new(tls)),
             domain: self.domain,
         })
     }
@@ -190,7 +190,7 @@ pub enum InnerTlsParameters {
     #[cfg(feature = "native-tls")]
     NativeTls(TlsConnector),
     #[cfg(feature = "rustls-tls")]
-    RustlsTls(ClientConfig),
+    RustlsTls(Arc<ClientConfig>),
 }
 
 impl TlsParameters {