imap::client::Client::authenticate: Base64 encode the result of the Authenticator.

Fixes issue #95.

Cargo.toml

@@ -30,6 +30,4 @@ regex = "1.0"
 bufstream = "0.1"
 imap-proto = "0.6"
 nom = "4.0"
-
-[dev-dependencies]
 base64 = "0.10"

src/client.rs

@@ -1,3 +1,4 @@
+extern crate base64;
 use bufstream::BufStream;
 use native_tls::{TlsConnector, TlsStream};
 use nom;
@@ -394,7 +395,7 @@ impl<T: Read + Write> Client<T> {
                     parse_authenticate_response(String::from_utf8(line).unwrap()),
                     self
                 );
-                let auth_response = authenticator.process(data);
+                let auth_response = base64::encode(authenticator.process(data).as_str());
 
                 ok_or_unauth_client_err!(
                     self.write_line(auth_response.into_bytes().as_slice()),
@@ -937,6 +938,28 @@ mod tests {
         );
     }
 
+    #[test]
+    fn authenticate() {
+        let response = b"+\r\n\
+                         a1 OK Logged in\r\n".to_vec();
+        let command =  "a1 AUTHENTICATE PLAIN\r\n\
+                        Zm9v\r\n";
+        let mock_stream = MockStream::new(response);
+        let client = Client::new(mock_stream);
+        enum Authenticate { Auth };
+        impl Authenticator for Authenticate {
+            fn process(&self, _: String) -> String {
+                "foo".to_string()
+            }
+        }
+        let auth = Authenticate::Auth;
+        let session = client.authenticate("PLAIN", auth).unwrap();
+        assert!(
+            session.stream.get_ref().written_buf == command.as_bytes().to_vec(),
+            "Invalid authenticate command"
+        );
+    }
+
     #[test]
     fn login() {
         let response = b"a1 OK Logged in\r\n".to_vec();