clippy: fix 1.49 lints (#530)

src/address/serde.rs

@@ -25,7 +25,7 @@ impl<'de> Deserialize<'de> for Address {
         enum Field {
             User,
             Domain,
-        };
+        }
 
         const FIELDS: &[&str] = &["user", "domain"];
 

src/message/mailbox/serde.rs

@@ -23,7 +23,7 @@ impl<'de> Deserialize<'de> for Mailbox {
         enum Field {
             Name,
             Email,
-        };
+        }
 
         const FIELDS: &[&str] = &["name", "email"];
 

src/message/mailbox/types.rs

@@ -258,26 +258,26 @@ impl Default for Mailboxes {
 }
 
 impl From<Mailbox> for Mailboxes {
-    fn from(single: Mailbox) -> Self {
-        Mailboxes(vec![single])
+    fn from(mailbox: Mailbox) -> Self {
+        Mailboxes(vec![mailbox])
     }
 }
 
-impl Into<Option<Mailbox>> for Mailboxes {
-    fn into(self) -> Option<Mailbox> {
-        self.into_iter().next()
+impl From<Mailboxes> for Option<Mailbox> {
+    fn from(mailboxes: Mailboxes) -> Option<Mailbox> {
+        mailboxes.into_iter().next()
     }
 }
 
 impl From<Vec<Mailbox>> for Mailboxes {
-    fn from(list: Vec<Mailbox>) -> Self {
-        Mailboxes(list)
+    fn from(vec: Vec<Mailbox>) -> Self {
+        Mailboxes(vec)
     }
 }
 
-impl Into<Vec<Mailbox>> for Mailboxes {
-    fn into(self) -> Vec<Mailbox> {
-        self.0
+impl From<Mailboxes> for Vec<Mailbox> {
+    fn from(mailboxes: Mailboxes) -> Vec<Mailbox> {
+        mailboxes.0
     }
 }
 

src/transport/smtp/async_transport.rs

@@ -126,8 +126,10 @@ where
     /// [`AsyncSmtpTransport::starttls_relay`](#method.starttls_relay) instead,
     /// if possible.
     pub fn builder_dangerous<T: Into<String>>(server: T) -> AsyncSmtpTransportBuilder {
-        let mut new = SmtpInfo::default();
-        new.server = server.into();
+        let new = SmtpInfo {
+            server: server.into(),
+            ..Default::default()
+        };
         AsyncSmtpTransportBuilder { info: new }
     }
 }

src/transport/smtp/error.rs

@@ -56,14 +56,14 @@ impl Display for Error {
         match *self {
             // Try to display the first line of the server's response that usually
             // contains a short humanly readable error message
-            Transient(ref err) => fmt.write_str(match err.first_line() {
-                Some(line) => line,
-                None => "transient error during SMTP transaction",
-            }),
-            Permanent(ref err) => fmt.write_str(match err.first_line() {
-                Some(line) => line,
-                None => "permanent error during SMTP transaction",
-            }),
+            Transient(ref err) => fmt.write_str(
+                err.first_line()
+                    .unwrap_or("transient error during SMTP transaction"),
+            ),
+            Permanent(ref err) => fmt.write_str(
+                err.first_line()
+                    .unwrap_or("permanent error during SMTP transaction"),
+            ),
             ResponseParsing(err) => fmt.write_str(err),
             ChallengeParsing(ref err) => err.fmt(fmt),
             Utf8Parsing(ref err) => err.fmt(fmt),

src/transport/smtp/transport.rs

@@ -96,8 +96,10 @@ impl SmtpTransport {
     /// [`SmtpTransport::starttls_relay`](#method.starttls_relay) instead,
     /// if possible.
     pub fn builder_dangerous<T: Into<String>>(server: T) -> SmtpTransportBuilder {
-        let mut new = SmtpInfo::default();
-        new.server = server.into();
+        let new = SmtpInfo {
+            server: server.into(),
+            ..Default::default()
+        };
 
         SmtpTransportBuilder {
             info: new,