Implement ser::Error for the value error

serde/src/de/value.rs

@@ -39,6 +39,7 @@ use lib::*;
 
 use de::{self, IntoDeserializer, Expected, SeqAccess};
 use private::de::size_hint;
+use ser;
 use self::private::{First, Second};
 
 ////////////////////////////////////////////////////////////////////////////////
@@ -74,6 +75,15 @@ impl de::Error for Error {
     }
 }
 
+impl ser::Error for Error {
+    fn custom<T>(msg: T) -> Self
+    where
+        T: Display,
+    {
+        de::Error::custom(msg)
+    }
+}
+
 impl Display for Error {
     #[cfg(any(feature = "std", feature = "collections"))]
     fn fmt(&self, formatter: &mut fmt::Formatter) -> Result<(), fmt::Error> {