Get the value of ESMTP parameters

src/smtp/client.rs

@@ -121,12 +121,17 @@ impl<T: Str> SmtpServerInfo<T> {
     }
 
     /// Checks if the server supports an ESMTP feature
-    fn supports_feature(&self, keyword: EsmtpParameter) -> bool {
+    fn supports_feature(&self, keyword: EsmtpParameter) -> Result<EsmtpParameter, ()> {
         match self.esmtp_features.clone() {
             Some(esmtp_features) => {
-                esmtp_features.contains(&keyword)
+                for feature in esmtp_features.iter() {
+                    if keyword.same_keyword_as(*feature) {
+                        return Ok(*feature);
+                    }
+                }
+                Err({})
             },
-            None => false
+            None => Err({})
         }
     }
 }
@@ -266,8 +271,8 @@ impl SmtpClient<StrBuf, TcpStream> {
 
         // Checks message encoding according to the server's capability
         // TODO : Add an encoding check.
-        if ! self.server_info.clone().unwrap().supports_feature(commands::EightBitMime) {
-            if message.clone().into_owned().is_ascii() {
+        if ! self.server_info.clone().unwrap().supports_feature(commands::EightBitMime).is_ok() {
+            if ! message.clone().into_owned().is_ascii() {
                 self.smtp_fail("Server does not accepts UTF-8 strings");
             }
         }
@@ -605,4 +610,24 @@ mod test {
         assert_eq!(SmtpServerInfo::parse_esmtp_response("me\r\n250-SIZE 42\r\n250 SIZE 43"),
             Some(vec!(commands::Size(42), commands::Size(43))));
     }
+    
+    #[test]
+    fn test_smtp_server_info_supports_feature() {
+        assert_eq!(SmtpServerInfo{
+            name: "name",
+            esmtp_features: Some(vec!(commands::EightBitMime))
+        }.supports_feature(commands::EightBitMime), Ok(commands::EightBitMime));
+        assert_eq!(SmtpServerInfo{
+            name: "name",
+            esmtp_features: Some(vec!(commands::Size(42), commands::EightBitMime))
+        }.supports_feature(commands::EightBitMime), Ok(commands::EightBitMime));
+        assert_eq!(SmtpServerInfo{
+            name: "name",
+            esmtp_features: Some(vec!(commands::Size(42), commands::EightBitMime))
+        }.supports_feature(commands::Size(0)), Ok(commands::Size(42)));
+        assert!(SmtpServerInfo{
+            name: "name",
+            esmtp_features: Some(vec!(commands::EightBitMime))
+        }.supports_feature(commands::Size(42)).is_err());
+    }
 }

src/smtp/commands.rs

@@ -97,7 +97,7 @@ impl Show for EsmtpParameter {
     fn fmt(&self, f: &mut Formatter) -> Result {
         f.buf.write(
             match self {
-                &EightBitMime  => "8BITMIME".to_owned(),
+                &EightBitMime   => "8BITMIME".to_owned(),
                 &Size(ref size) => format!("SIZE={}", size)
             }.as_bytes()
         )
@@ -121,6 +121,19 @@ impl FromStr for EsmtpParameter {
     }
 }
 
+impl EsmtpParameter {
+    /// Checks if the ESMTP keyword is the same
+    pub fn same_keyword_as(&self, other: EsmtpParameter) -> bool {
+        if *self == other {
+            return true;
+        }
+        match (*self, other) {
+            (Size(_), Size(_)) => true,
+            _                  => false
+        }
+    }
+}
+
 #[cfg(test)]
 mod test {
     use super::{SmtpCommand, EsmtpParameter};
@@ -135,6 +148,14 @@ mod test {
         );
     }
 
+    #[test]
+    fn test_esmtp_parameter_same_keyword_as() {
+        assert_eq!(super::EightBitMime.same_keyword_as(super::EightBitMime), true);
+        assert_eq!(super::Size(42).same_keyword_as(super::Size(42)), true);
+        assert_eq!(super::Size(42).same_keyword_as(super::Size(43)), true);
+        assert_eq!(super::Size(42).same_keyword_as(super::EightBitMime), false);
+    }
+
     #[test]
     fn test_esmtp_parameter_fmt() {
         assert_eq!(format!("{}", super::EightBitMime), "8BITMIME".to_owned());