message, iq, presence: Return an Unknown instead of an error when the element is unknown.

src/iq.rs

@@ -29,6 +29,8 @@ pub enum IqPayload {
     IBB(IBB),
     Jingle(Jingle),
     Ping(Ping),
+
+    Unknown(Element),
 }
 
 impl<'a> TryFrom<&'a Element> for IqPayload {
@@ -50,7 +52,7 @@ impl<'a> TryFrom<&'a Element> for IqPayload {
             // XEP-0199
             ("ping", ns::PING) => IqPayload::Ping(Ping::try_from(elem)?),
 
-            _ => return Err(Error::ParseError("Unknown iq payload."))
+            _ => IqPayload::Unknown(elem.clone()),
         })
     }
 }
@@ -164,6 +166,8 @@ impl<'a> Into<Element> for &'a IqPayload {
             IqPayload::IBB(ref ibb) => ibb.into(),
             IqPayload::Jingle(ref jingle) => jingle.into(),
             IqPayload::Ping(ref ping) => ping.into(),
+
+            IqPayload::Unknown(ref elem) => elem.clone(),
         }
     }
 }

src/message.rs

@@ -36,6 +36,8 @@ pub enum MessagePayload {
     MessageCorrect(Replace),
     ExplicitMessageEncryption(ExplicitMessageEncryption),
     StanzaId(StanzaId),
+
+    Unknown(Element),
 }
 
 impl<'a> TryFrom<&'a Element> for MessagePayload {
@@ -71,7 +73,7 @@ impl<'a> TryFrom<&'a Element> for MessagePayload {
             // XEP-0380
             ("encryption", ns::EME) => MessagePayload::ExplicitMessageEncryption(ExplicitMessageEncryption::try_from(elem)?),
 
-            _ => return Err(Error::ParseError("Unknown message payload."))
+            _ => MessagePayload::Unknown(elem.clone()),
         })
     }
 }
@@ -87,6 +89,8 @@ impl<'a> Into<Element> for &'a MessagePayload {
             MessagePayload::MessageCorrect(ref replace) => replace.into(),
             MessagePayload::ExplicitMessageEncryption(ref eme) => eme.into(),
             MessagePayload::StanzaId(ref stanza_id) => stanza_id.into(),
+
+            MessagePayload::Unknown(ref elem) => elem.clone(),
         }
     }
 }

src/presence.rs

@@ -51,6 +51,8 @@ pub enum PresencePayload {
     StanzaError(StanzaError),
     Delay(Delay),
     ECaps2(ECaps2),
+
+    Unknown(Element),
 }
 
 impl<'a> TryFrom<&'a Element> for PresencePayload {
@@ -66,7 +68,7 @@ impl<'a> TryFrom<&'a Element> for PresencePayload {
             // XEP-0390
             ("c", ns::ECAPS2) => PresencePayload::ECaps2(ECaps2::try_from(elem)?),
 
-            _ => return Err(Error::ParseError("Unknown presence payload."))
+            _ => PresencePayload::Unknown(elem.clone()),
         })
     }
 }
@@ -77,6 +79,8 @@ impl<'a> Into<Element> for &'a PresencePayload {
             PresencePayload::StanzaError(ref stanza_error) => stanza_error.into(),
             PresencePayload::Delay(ref delay) => delay.into(),
             PresencePayload::ECaps2(ref ecaps2) => ecaps2.into(),
+
+            PresencePayload::Unknown(ref elem) => elem.clone(),
         }
     }
 }