Use smtp-sink for benchmarks

.travis.yml

@@ -9,6 +9,7 @@ before_script:
   - sudo apt-get update -qq
   - sudo apt-get install -y postfix
   - pip install 'travis-cargo<0.2' --user && export PATH=$HOME/.local/bin:$PATH
+  - smtp-sink 2525 1000&
 script:
   - |
       travis-cargo build &&

benches/smtp.rs

@@ -11,7 +11,7 @@ use lettre::email::EmailBuilder;
 #[bench]
 fn bench_simple_send(b: &mut test::Bencher) {
     b.iter(|| {
-        let sender = SmtpTransportBuilder::localhost().unwrap().build();
+        let sender = SmtpTransportBuilder::new("127.0.0.1:2525").unwrap().build();
         let mut mailer = Mailer::new(sender);
         let email = EmailBuilder::new()
                         .to("root@localhost")
@@ -28,7 +28,7 @@ fn bench_simple_send(b: &mut test::Bencher) {
 
 #[bench]
 fn bench_reuse_send(b: &mut test::Bencher) {
-    let sender = SmtpTransportBuilder::localhost().unwrap().connection_reuse(true).build();
+    let sender = SmtpTransportBuilder::new("127.0.0.1:2525").unwrap().connection_reuse(true).build();
     let mut mailer = Mailer::new(sender);
     b.iter(|| {
         let email = EmailBuilder::new()