From 151635f5fb433fa3aaea4a3614907b928c3fb254 Mon Sep 17 00:00:00 2001
From: Emmanuel Gil Peyrot <linkmauve@linkmauve.fr>
Date: Sat, 6 May 2017 20:07:03 +0100
Subject: [PATCH] receipts: Switch to Into/TryFrom.

---
 src/message.rs  |  8 +++---
 src/receipts.rs | 67 ++++++++++++++++++++++++++-----------------------
 2 files changed, 40 insertions(+), 35 deletions(-)

diff --git a/src/message.rs b/src/message.rs
index 6fcc681..4800145 100644
--- a/src/message.rs
+++ b/src/message.rs
@@ -18,7 +18,7 @@ use ns;
 use body;
 use stanza_error;
 use chatstates;
-use receipts;
+use receipts::Receipt;
 use delay;
 use attention::Attention;
 use message_correct;
@@ -30,7 +30,7 @@ pub enum MessagePayload {
     Body(body::Body),
     StanzaError(stanza_error::StanzaError),
     ChatState(chatstates::ChatState),
-    Receipt(receipts::Receipt),
+    Receipt(Receipt),
     Delay(delay::Delay),
     Attention(Attention),
     MessageCorrect(message_correct::Replace),
@@ -117,7 +117,7 @@ pub fn parse_message(root: &Element) -> Result<Message, Error> {
             Some(MessagePayload::StanzaError(stanza_error))
         } else if let Ok(chatstate) = chatstates::parse_chatstate(elem) {
             Some(MessagePayload::ChatState(chatstate))
-        } else if let Ok(receipt) = receipts::parse_receipt(elem) {
+        } else if let Ok(receipt) = Receipt::try_from(elem) {
             Some(MessagePayload::Receipt(receipt))
         } else if let Ok(delay) = delay::parse_delay(elem) {
             Some(MessagePayload::Delay(delay))
@@ -150,7 +150,7 @@ pub fn serialise_payload(payload: &MessagePayload) -> Element {
         MessagePayload::StanzaError(ref stanza_error) => stanza_error::serialise(stanza_error),
         MessagePayload::Attention(ref attention) => attention.into(),
         MessagePayload::ChatState(ref chatstate) => chatstates::serialise(chatstate),
-        MessagePayload::Receipt(ref receipt) => receipts::serialise(receipt),
+        MessagePayload::Receipt(ref receipt) => receipt.into(),
         MessagePayload::Delay(ref delay) => delay::serialise(delay),
         MessagePayload::MessageCorrect(ref replace) => message_correct::serialise(replace),
         MessagePayload::ExplicitMessageEncryption(ref eme) => eme::serialise(eme),
diff --git a/src/receipts.rs b/src/receipts.rs
index 3dc3b78..27392fb 100644
--- a/src/receipts.rs
+++ b/src/receipts.rs
@@ -4,6 +4,8 @@
 // License, v. 2.0. If a copy of the MPL was not distributed with this
 // file, You can obtain one at http://mozilla.org/MPL/2.0/.
 
+use std::convert::TryFrom;
+
 use minidom::Element;
 
 use error::Error;
@@ -16,59 +18,62 @@ pub enum Receipt {
     Received(String),
 }
 
-pub fn parse_receipt(root: &Element) -> Result<Receipt, Error> {
-    for _ in root.children() {
-        return Err(Error::ParseError("Unknown child in receipt element."));
-    }
-    if root.is("request", ns::RECEIPTS) {
-        Ok(Receipt::Request)
-    } else if root.is("received", ns::RECEIPTS) {
-        let id = root.attr("id").unwrap_or("").to_owned();
-        Ok(Receipt::Received(id))
-    } else {
-        Err(Error::ParseError("This is not a receipt element."))
+impl<'a> TryFrom<&'a Element> for Receipt {
+    type Error = Error;
+
+    fn try_from(elem: &'a Element) -> Result<Receipt, Error> {
+        for _ in elem.children() {
+            return Err(Error::ParseError("Unknown child in receipt element."));
+        }
+        if elem.is("request", ns::RECEIPTS) {
+            Ok(Receipt::Request)
+        } else if elem.is("received", ns::RECEIPTS) {
+            let id = elem.attr("id").unwrap_or("").to_owned();
+            Ok(Receipt::Received(id))
+        } else {
+            Err(Error::ParseError("This is not a receipt element."))
+        }
     }
 }
 
-pub fn serialise(receipt: &Receipt) -> Element {
-    match *receipt {
-        Receipt::Request => Element::builder("request")
-                                    .ns(ns::RECEIPTS)
-                                    .build(),
-        Receipt::Received(ref id) => Element::builder("received")
-                                             .ns(ns::RECEIPTS)
-                                             .attr("id", id.clone())
-                                             .build(),
+impl<'a> Into<Element> for &'a Receipt {
+    fn into(self) -> Element {
+        match *self {
+            Receipt::Request => Element::builder("request")
+                                        .ns(ns::RECEIPTS)
+                                        .build(),
+            Receipt::Received(ref id) => Element::builder("received")
+                                                 .ns(ns::RECEIPTS)
+                                                 .attr("id", id.clone())
+                                                 .build(),
+        }
     }
 }
 
 #[cfg(test)]
 mod tests {
-    use minidom::Element;
-    //use error::Error;
-    use receipts;
-    use ns;
+    use super::*;
 
     #[test]
     fn test_simple() {
         let elem: Element = "<request xmlns='urn:xmpp:receipts'/>".parse().unwrap();
-        receipts::parse_receipt(&elem).unwrap();
+        Receipt::try_from(&elem).unwrap();
 
         let elem: Element = "<received xmlns='urn:xmpp:receipts'/>".parse().unwrap();
-        receipts::parse_receipt(&elem).unwrap();
+        Receipt::try_from(&elem).unwrap();
 
         let elem: Element = "<received xmlns='urn:xmpp:receipts' id='coucou'/>".parse().unwrap();
-        receipts::parse_receipt(&elem).unwrap();
+        Receipt::try_from(&elem).unwrap();
     }
 
     #[test]
     fn test_serialise() {
-        let receipt = receipts::Receipt::Request;
-        let elem = receipts::serialise(&receipt);
+        let receipt = Receipt::Request;
+        let elem: Element = (&receipt).into();
         assert!(elem.is("request", ns::RECEIPTS));
 
-        let receipt = receipts::Receipt::Received("coucou".to_owned());
-        let elem = receipts::serialise(&receipt);
+        let receipt = Receipt::Received("coucou".to_owned());
+        let elem: Element = (&receipt).into();
         assert!(elem.is("received", ns::RECEIPTS));
         assert_eq!(elem.attr("id"), Some("coucou"));
     }