Update to rust HEAD

serde2/src/json/error.rs

@@ -39,6 +39,8 @@ pub enum ErrorCode {
 
 impl fmt::Debug for ErrorCode {
     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        use std::fmt::Debug;
+
         match *self {
             //ErrorCode::ConversionError(ref token) => write!(f, "failed to convert {}", token),
             ErrorCode::EOFWhileParsingList => "EOF While parsing list".fmt(f),
@@ -91,7 +93,7 @@ impl error::Error for Error {
     fn description(&self) -> &str {
         match *self {
             Error::SyntaxError(..) => "syntax error",
-            Error::IoError(_) => "input/output error",
+            Error::IoError(ref error) => error.description().as_slice(),
             /*
             Error::ExpectedError(ref expected, _) => &expected,
             Error::MissingFieldError(_) => "missing field",
@@ -100,6 +102,13 @@ impl error::Error for Error {
         }
     }
 
+    fn cause(&self) -> Option<&error::Error> {
+        match *self {
+            Error::IoError(ref error) => Some(error),
+            _ => None,
+        }
+    }
+
 }
 
 impl fmt::Display for Error {

serde2/src/json/value.rs

@@ -67,7 +67,7 @@ impl fmt::Debug for Value {
 
 pub fn to_value<T>(value: &T) -> Value where T: ser::Serialize {
     let mut writer = Writer::new();
-    writer.visit(value).unwrap();
+    writer.visit(value).ok().unwrap();
     writer.unwrap()
 }