From 033cbe777bc3908d2420f35669d7e9d515b31a5e Mon Sep 17 00:00:00 2001
From: Emmanuel Gil Peyrot <linkmauve@linkmauve.fr>
Date: Thu, 4 May 2017 01:31:13 +0100
Subject: [PATCH] ping: Port to TryFrom/Into.

---
 src/iq.rs   |  8 ++++----
 src/ping.rs | 37 ++++++++++++++++++++++---------------
 2 files changed, 26 insertions(+), 19 deletions(-)

diff --git a/src/iq.rs b/src/iq.rs
index 8a4e70e..d1e3eea 100644
--- a/src/iq.rs
+++ b/src/iq.rs
@@ -20,7 +20,7 @@ use stanza_error;
 use disco;
 use ibb;
 use jingle::Jingle;
-use ping;
+use ping::Ping;
 
 /// Lists every known payload of a `<iq/>`.
 #[derive(Debug, Clone)]
@@ -28,7 +28,7 @@ pub enum IqPayload {
     Disco(disco::Disco),
     IBB(ibb::IBB),
     Jingle(Jingle),
-    Ping(ping::Ping),
+    Ping(Ping),
 }
 
 #[derive(Debug, Clone)]
@@ -101,7 +101,7 @@ pub fn parse_iq(root: &Element) -> Result<Iq, Error> {
                 Some(IqPayload::IBB(ibb))
             } else if let Ok(jingle) = Jingle::try_from(elem) {
                 Some(IqPayload::Jingle(jingle))
-            } else if let Ok(ping) = ping::parse_ping(elem) {
+            } else if let Ok(ping) = Ping::try_from(elem) {
                 Some(IqPayload::Ping(ping))
             } else {
                 None
@@ -155,7 +155,7 @@ pub fn serialise_payload(payload: &IqPayload) -> Element {
         IqPayload::Disco(ref disco) => disco::serialise_disco(disco),
         IqPayload::IBB(ref ibb) => ibb::serialise(ibb),
         IqPayload::Jingle(ref jingle) => jingle.into(),
-        IqPayload::Ping(_) => ping::serialise_ping(),
+        IqPayload::Ping(ref ping) => ping.into(),
     }
 }
 
diff --git a/src/ping.rs b/src/ping.rs
index b6b6f61..4fe2fd8 100644
--- a/src/ping.rs
+++ b/src/ping.rs
@@ -5,6 +5,8 @@
 // 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;
@@ -14,37 +16,42 @@ use ns;
 #[derive(Debug, Clone)]
 pub struct Ping;
 
-pub fn parse_ping(root: &Element) -> Result<Ping, Error> {
-    if !root.is("ping", ns::PING) {
-        return Err(Error::ParseError("This is not a ping element."));
-    }
+impl<'a> TryFrom<&'a Element> for Ping {
+    type Error = Error;
 
-    for _ in root.children() {
-        return Err(Error::ParseError("Unknown child in ping element."));
+    fn try_from(elem: &'a Element) -> Result<Ping, Error> {
+        if !elem.is("ping", ns::PING) {
+            return Err(Error::ParseError("This is not a ping element."));
+        }
+        for _ in elem.children() {
+            return Err(Error::ParseError("Unknown child in ping element."));
+        }
+        Ok(Ping)
     }
-    Ok(Ping {  })
 }
 
-pub fn serialise_ping() -> Element {
-    Element::builder("ping").ns(ns::PING).build()
+impl<'a> Into<Element> for &'a Ping {
+    fn into(self) -> Element {
+        Element::builder("ping")
+                .ns(ns::PING)
+                .build()
+    }
 }
 
 #[cfg(test)]
 mod tests {
-    use minidom::Element;
-    use error::Error;
-    use ping;
+    use super::*;
 
     #[test]
     fn test_simple() {
         let elem: Element = "<ping xmlns='urn:xmpp:ping'/>".parse().unwrap();
-        ping::parse_ping(&elem).unwrap();
+        Ping::try_from(&elem).unwrap();
     }
 
     #[test]
     fn test_invalid() {
         let elem: Element = "<ping xmlns='urn:xmpp:ping'><coucou/></ping>".parse().unwrap();
-        let error = ping::parse_ping(&elem).unwrap_err();
+        let error = Ping::try_from(&elem).unwrap_err();
         let message = match error {
             Error::ParseError(string) => string,
             _ => panic!(),
@@ -56,7 +63,7 @@ mod tests {
     #[ignore]
     fn test_invalid_attribute() {
         let elem: Element = "<ping xmlns='urn:xmpp:ping' coucou=''/>".parse().unwrap();
-        let error = ping::parse_ping(&elem).unwrap_err();
+        let error = Ping::try_from(&elem).unwrap_err();
         let message = match error {
             Error::ParseError(string) => string,
             _ => panic!(),