Fix decoding for `CurrentUser.discriminator`

Due to the serde 1.0 upgrade, integers are no longer automatically
deserialized from Strings. To resolve this, create a visitor that
performs the operation based on the input.

2 files changed, 39 insertions, 0 deletions

diff --git a/src/model/user.rs b/src/model/user.rs
index 8f7349c..686d394 100644
--- a/src/model/user.rs
+++ b/src/model/user.rs
@@ -1,5 +1,6 @@
 use serde_json;
 use std::{fmt, mem};
+use super::utils::deserialize_u16;
 use super::*;
 use time::Timespec;
 use ::client::rest::{self, GuildPagination};
@@ -54,6 +55,7 @@ pub struct CurrentUser {
     pub avatar: Option<String>,
     #[serde(default)]
     pub bot: bool,
+    #[serde(deserialize_with="deserialize_u16")]
     pub discriminator: u16,
     pub email: Option<String>,
     pub mfa_enabled: bool,
diff --git a/src/model/utils.rs b/src/model/utils.rs
index 309b9de..a01f134 100644
--- a/src/model/utils.rs
+++ b/src/model/utils.rs
@@ -115,6 +115,11 @@ pub fn deserialize_users<'de, D: Deserializer<'de>>(deserializer: D)
     Ok(users)
 }
 
+pub fn deserialize_u16<'de, D: Deserializer<'de>>(deserializer: D)
+    -> StdResult<u16, D::Error> {
+    deserializer.deserialize_u16(U16Visitor)
+}
+
 pub fn deserialize_u64<'de, D: Deserializer<'de>>(deserializer: D)
     -> StdResult<u64, D::Error> {
     deserializer.deserialize_u64(U64Visitor)
@@ -161,6 +166,38 @@ pub fn user_has_perms(channel_id: ChannelId, mut permissions: Permissions) -> Re
     Ok(permissions.is_empty())
 }
 
+pub struct U16Visitor;
+
+impl<'de> Visitor<'de> for U16Visitor {
+    type Value = u16;
+
+    fn expecting(&self, formatter: &mut Formatter) -> FmtResult {
+        formatter.write_str("identifier")
+    }
+
+    fn visit_str<E: DeError>(self, v: &str) -> StdResult<Self::Value, E> {
+        match v.parse::<u16>() {
+            Ok(v) => Ok(v),
+            Err(_) => {
+                let mut s = String::new();
+                s.push_str("Unknown ");
+                s.push_str(stringify!($name));
+                s.push_str(" value: ");
+                s.push_str(v);
+
+                Err(DeError::custom(s))
+            },
+        }
+    }
+
+    fn visit_i64<E: DeError>(self, v: i64) -> StdResult<Self::Value, E> {
+        Ok(v as u16)
+    }
+
+    fn visit_u64<E: DeError>(self, v: u64) -> StdResult<Self::Value, E> {
+        Ok(v as u16)
+    }
+}
 
 pub struct U64Visitor;