From 8e1d5e7983ea580def4ac749e96faffd19f85015 Mon Sep 17 00:00:00 2001
From: Emmanuel Gil Peyrot <linkmauve@linkmauve.fr>
Date: Sat, 27 May 2017 22:10:00 +0100
Subject: [PATCH] disco: Make xml:lang a proper Option and rename it to lang.

---
 src/caps.rs   | 5 +++--
 src/disco.rs  | 8 ++++----
 src/ecaps2.rs | 2 +-
 3 files changed, 8 insertions(+), 7 deletions(-)

diff --git a/src/caps.rs b/src/caps.rs
index 4b504241..b7753a19 100644
--- a/src/caps.rs
+++ b/src/caps.rs
@@ -91,8 +91,9 @@ fn compute_features(features: &[Feature]) -> Vec<u8> {
 
 fn compute_identities(identities: &[Identity]) -> Vec<u8> {
     compute_items(identities, |identity| {
-        let empty = String::new();
-        let string = format!("{}/{}/{}/{}", identity.category, identity.type_, identity.xml_lang, match identity.name { Some(ref name) => name, None => &empty });
+        let lang = identity.lang.clone().unwrap_or_default();
+        let name = identity.name.clone().unwrap_or_default();
+        let string = format!("{}/{}/{}/{}", identity.category, identity.type_, lang, name);
         let bytes = string.as_bytes();
         let mut vec = Vec::with_capacity(bytes.len());
         vec.extend_from_slice(bytes);
diff --git a/src/disco.rs b/src/disco.rs
index 46d25dec..486f81e9 100644
--- a/src/disco.rs
+++ b/src/disco.rs
@@ -37,7 +37,7 @@ impl IntoElements for Feature {
 pub struct Identity {
     pub category: String, // TODO: use an enum here.
     pub type_: String, // TODO: use an enum here.
-    pub xml_lang: String,
+    pub lang: Option<String>,
     pub name: Option<String>,
 }
 
@@ -47,7 +47,7 @@ impl Into<Element> for Identity {
                 .ns(ns::DISCO_INFO)
                 .attr("category", self.category)
                 .attr("type", self.type_)
-                .attr("xml:lang", self.xml_lang)
+                .attr("xml:lang", self.lang)
                 .attr("name", self.name)
                 .build()
     }
@@ -98,12 +98,12 @@ impl TryFrom<Element> for Disco {
                     return Err(Error::ParseError("Identity must have a non-empty 'type' attribute."))
                 }
 
-                let lang = get_attr!(child, "xml:lang", default);
+                let lang = get_attr!(child, "xml:lang", optional);
                 let name = get_attr!(child, "name", optional);
                 identities.push(Identity {
                     category: category,
                     type_: type_,
-                    xml_lang: lang,
+                    lang: lang,
                     name: name,
                 });
             } else if child.is("x", ns::DATA_FORMS) {
diff --git a/src/ecaps2.rs b/src/ecaps2.rs
index 09f1516e..7d9279bb 100644
--- a/src/ecaps2.rs
+++ b/src/ecaps2.rs
@@ -88,7 +88,7 @@ fn compute_identities(identities: &[Identity]) -> Vec<u8> {
     compute_items(identities, 0x1c, |identity| {
         let mut bytes = compute_item(&identity.category);
         bytes.append(&mut compute_item(&identity.type_));
-        bytes.append(&mut compute_item(&identity.xml_lang));
+        bytes.append(&mut compute_item(&identity.lang.clone().unwrap_or_default()));
         bytes.append(&mut compute_item(&identity.name.clone().unwrap_or_default()));
         bytes.push(0x1e);
         bytes