Release 1.0.16

This functionality is covered well enough by the std::net types.

CONTRIBUTING.md

@@ -22,7 +22,7 @@ efforts from contributors on the same issue.
   master you may be asked to rebase your changes.
 
 - Commits should be as small as possible, while ensuring that each commit is
-  correct independently (i.e., each commit should compile and pass tests). 
+  correct independently (i.e., each commit should compile and pass tests).
 
 - If your patch is not getting reviewed or you need a specific person to review
   it, you can @-reply a reviewer asking for a review in the pull request or a

serde/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "serde"
-version = "1.0.14" # remember to update html_root_url
+version = "1.0.16" # remember to update html_root_url
 authors = ["Erick Tryzelaar <erick.tryzelaar@gmail.com>", "David Tolnay <dtolnay@gmail.com>"]
 license = "MIT/Apache-2.0"
 description = "A generic serialization/deserialization framework"

serde/src/de/impls.rs

@@ -869,37 +869,206 @@ map_impl!(
 ////////////////////////////////////////////////////////////////////////////////
 
 #[cfg(feature = "std")]
-macro_rules! parse_impl {
-    ($ty:ty) => {
+macro_rules! parse_ip_impl {
+    ($ty:ty; $size: expr) => {
         impl<'de> Deserialize<'de> for $ty {
             fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
             where
                 D: Deserializer<'de>,
             {
-                let s = try!(String::deserialize(deserializer));
-                s.parse().map_err(Error::custom)
+                if deserializer.is_human_readable() {
+                    let s = try!(String::deserialize(deserializer));
+                    s.parse().map_err(Error::custom)
+                } else {
+                    <[u8; $size]>::deserialize(deserializer).map(<$ty>::from)
+                }
             }
         }
     }
 }
 
 #[cfg(feature = "std")]
-parse_impl!(net::IpAddr);
+macro_rules! variant_identifier {
+    (
+        $name_kind: ident ( $($variant: ident; $bytes: expr; $index: expr),* )
+        $expecting_message: expr,
+        $variants_name: ident
+    ) => {
+        enum $name_kind {
+            $( $variant ),*
+        }
+
+        static $variants_name: &'static [&'static str] = &[ $( stringify!($variant) ),*];
+
+        impl<'de> Deserialize<'de> for $name_kind {
+            fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
+            where
+                D: Deserializer<'de>,
+            {
+                struct KindVisitor;
+
+                impl<'de> Visitor<'de> for KindVisitor {
+                    type Value = $name_kind;
+
+                    fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
+                        formatter.write_str($expecting_message)
+                    }
+
+                    fn visit_u32<E>(self, value: u32) -> Result<Self::Value, E>
+                    where
+                        E: Error,
+                    {
+                        match value {
+                            $(
+                                $index => Ok($name_kind :: $variant),
+                            )*
+                            _ => Err(Error::invalid_value(Unexpected::Unsigned(value as u64), &self),),
+                        }
+                    }
+
+                    fn visit_str<E>(self, value: &str) -> Result<Self::Value, E>
+                    where
+                        E: Error,
+                    {
+                        match value {
+                            $(
+                                stringify!($variant) => Ok($name_kind :: $variant),
+                            )*
+                            _ => Err(Error::unknown_variant(value, $variants_name)),
+                        }
+                    }
+
+                    fn visit_bytes<E>(self, value: &[u8]) -> Result<Self::Value, E>
+                    where
+                        E: Error,
+                    {
+                        match value {
+                            $(
+                                $bytes => Ok($name_kind :: $variant),
+                            )*
+                            _ => {
+                                match str::from_utf8(value) {
+                                    Ok(value) => Err(Error::unknown_variant(value, $variants_name)),
+                                    Err(_) => Err(Error::invalid_value(Unexpected::Bytes(value), &self)),
+                                }
+                            }
+                        }
+                    }
+                }
+
+                deserializer.deserialize_identifier(KindVisitor)
+            }
+        }
+    }
+}
 
 #[cfg(feature = "std")]
-parse_impl!(net::Ipv4Addr);
+macro_rules! deserialize_enum {
+    (
+        $name: ident $name_kind: ident ( $($variant: ident; $bytes: expr; $index: expr),* )
+        $expecting_message: expr,
+        $deserializer: expr
+    ) => {
+        variant_identifier!{
+            $name_kind ( $($variant; $bytes; $index),* )
+            $expecting_message,
+            VARIANTS
+        }
+
+        struct EnumVisitor;
+        impl<'de> Visitor<'de> for EnumVisitor {
+            type Value = $name;
+
+            fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
+                formatter.write_str(concat!("a ", stringify!($name)))
+            }
+
+
+            fn visit_enum<A>(self, data: A) -> Result<Self::Value, A::Error>
+            where
+                A: EnumAccess<'de>,
+            {
+                match try!(data.variant()) {
+                    $(
+                        ($name_kind :: $variant, v) => v.newtype_variant().map($name :: $variant),
+                    )*
+                }
+            }
+        }
+        $deserializer.deserialize_enum(stringify!($name), VARIANTS, EnumVisitor)
+    }
+}
 
 #[cfg(feature = "std")]
-parse_impl!(net::Ipv6Addr);
+impl<'de> Deserialize<'de> for net::IpAddr {
+    fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
+    where
+        D: Deserializer<'de>,
+    {
+        if deserializer.is_human_readable() {
+            let s = try!(String::deserialize(deserializer));
+            s.parse().map_err(Error::custom)
+        } else {
+            use lib::net::IpAddr;
+            deserialize_enum!{
+                IpAddr IpAddrKind (V4; b"V4"; 0, V6; b"V6"; 1)
+                "`V4` or `V6`",
+                deserializer
+            }
+        }
+    }
+}
 
 #[cfg(feature = "std")]
-parse_impl!(net::SocketAddr);
+parse_ip_impl!(net::Ipv4Addr; 4);
 
 #[cfg(feature = "std")]
-parse_impl!(net::SocketAddrV4);
+parse_ip_impl!(net::Ipv6Addr; 16);
 
 #[cfg(feature = "std")]
-parse_impl!(net::SocketAddrV6);
+macro_rules! parse_socket_impl {
+    ($ty:ty, $new: expr) => {
+        impl<'de> Deserialize<'de> for $ty {
+            fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
+            where
+                D: Deserializer<'de>,
+            {
+                if deserializer.is_human_readable() {
+                    let s = try!(String::deserialize(deserializer));
+                    s.parse().map_err(Error::custom)
+                } else {
+                    <(_, u16)>::deserialize(deserializer).map(|(ip, port)| $new(ip, port))
+                }
+            }
+        }
+    }
+}
+
+#[cfg(feature = "std")]
+impl<'de> Deserialize<'de> for net::SocketAddr {
+    fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
+    where
+        D: Deserializer<'de>,
+    {
+        if deserializer.is_human_readable() {
+            let s = try!(String::deserialize(deserializer));
+            s.parse().map_err(Error::custom)
+        } else {
+            use lib::net::SocketAddr;
+            deserialize_enum!{
+                SocketAddr SocketAddrKind (V4; b"V4"; 0, V6; b"V6"; 1)
+                "`V4` or `V6`",
+                deserializer
+            }
+        }
+    }
+}
+
+#[cfg(feature = "std")]
+parse_socket_impl!(net::SocketAddrV4, net::SocketAddrV4::new);
+
+#[cfg(feature = "std")]
+parse_socket_impl!(net::SocketAddrV6, |ip, port| net::SocketAddrV6::new(ip, port, 0, 0));
 
 ////////////////////////////////////////////////////////////////////////////////
 
@@ -984,70 +1153,10 @@ impl<'de> Deserialize<'de> for PathBuf {
 //    #[derive(Deserialize)]
 //    #[serde(variant_identifier)]
 #[cfg(all(feature = "std", any(unix, windows)))]
-enum OsStringKind {
-    Unix,
-    Windows,
-}
-
-#[cfg(all(feature = "std", any(unix, windows)))]
-static OSSTR_VARIANTS: &'static [&'static str] = &["Unix", "Windows"];
-
-#[cfg(all(feature = "std", any(unix, windows)))]
-impl<'de> Deserialize<'de> for OsStringKind {
-    fn deserialize<D>(deserializer: D) -> Result<OsStringKind, D::Error>
-    where
-        D: Deserializer<'de>,
-    {
-        struct KindVisitor;
-
-        impl<'de> Visitor<'de> for KindVisitor {
-            type Value = OsStringKind;
-
-            fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
-                formatter.write_str("`Unix` or `Windows`")
-            }
-
-            fn visit_u32<E>(self, value: u32) -> Result<OsStringKind, E>
-            where
-                E: Error,
-            {
-                match value {
-                    0 => Ok(OsStringKind::Unix),
-                    1 => Ok(OsStringKind::Windows),
-                    _ => Err(Error::invalid_value(Unexpected::Unsigned(value as u64), &self),),
-                }
-            }
-
-            fn visit_str<E>(self, value: &str) -> Result<OsStringKind, E>
-            where
-                E: Error,
-            {
-                match value {
-                    "Unix" => Ok(OsStringKind::Unix),
-                    "Windows" => Ok(OsStringKind::Windows),
-                    _ => Err(Error::unknown_variant(value, OSSTR_VARIANTS)),
-                }
-            }
-
-            fn visit_bytes<E>(self, value: &[u8]) -> Result<OsStringKind, E>
-            where
-                E: Error,
-            {
-                match value {
-                    b"Unix" => Ok(OsStringKind::Unix),
-                    b"Windows" => Ok(OsStringKind::Windows),
-                    _ => {
-                        match str::from_utf8(value) {
-                            Ok(value) => Err(Error::unknown_variant(value, OSSTR_VARIANTS)),
-                            Err(_) => Err(Error::invalid_value(Unexpected::Bytes(value), &self)),
-                        }
-                    }
-                }
-            }
-        }
-
-        deserializer.deserialize_identifier(KindVisitor)
-    }
+variant_identifier!{
+    OsStringKind (Unix; b"Unix"; 0, Windows; b"Windows"; 1)
+    "`Unix` or `Windows`",
+    OSSTR_VARIANTS
 }
 
 #[cfg(all(feature = "std", any(unix, windows)))]

serde/src/de/mod.rs

@@ -1011,6 +1011,72 @@ pub trait Deserializer<'de>: Sized {
     fn deserialize_ignored_any<V>(self, visitor: V) -> Result<V::Value, Self::Error>
     where
         V: Visitor<'de>;
+
+    /// Determine whether `Deserialize` implementations should expect to
+    /// deserialize their human-readable form.
+    ///
+    /// Some types have a human-readable form that may be somewhat expensive to
+    /// construct, as well as a binary form that is compact and efficient.
+    /// Generally text-based formats like JSON and YAML will prefer to use the
+    /// human-readable one and binary formats like Bincode will prefer the
+    /// compact one.
+    ///
+    /// ```
+    /// # use std::ops::Add;
+    /// # use std::str::FromStr;
+    /// #
+    /// # struct Timestamp;
+    /// #
+    /// # impl FromStr for Timestamp {
+    /// #     type Err = String;
+    /// #     fn from_str(_: &str) -> Result<Self, Self::Err> {
+    /// #         unimplemented!()
+    /// #     }
+    /// # }
+    /// #
+    /// # struct Duration;
+    /// #
+    /// # impl Duration {
+    /// #     fn seconds(_: u64) -> Self { unimplemented!() }
+    /// # }
+    /// #
+    /// # impl Add<Duration> for () {
+    /// #     type Output = Timestamp;
+    /// #     fn add(self, _: Duration) -> Self::Output {
+    /// #         unimplemented!()
+    /// #     }
+    /// # }
+    /// #
+    /// use serde::de::{self, Deserialize, Deserializer};
+    ///
+    /// impl<'de> Deserialize<'de> for Timestamp {
+    ///     fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
+    ///         where D: Deserializer<'de>
+    ///     {
+    ///         if deserializer.is_human_readable() {
+    ///             // Deserialize from a human-readable string like "2015-05-15T17:01:00Z".
+    ///             let s = String::deserialize(deserializer)?;
+    ///             Timestamp::from_str(&s).map_err(de::Error::custom)
+    ///         } else {
+    /// # // Make it look like an associated constant but compile on older rustc.
+    /// # mod Timestamp { pub const EPOCH: () = (); }
+    ///             // Deserialize from a compact binary representation, seconds since
+    ///             // the Unix epoch.
+    ///             let n = u64::deserialize(deserializer)?;
+    ///             Ok(Timestamp::EPOCH + Duration::seconds(n))
+    ///         }
+    ///     }
+    /// }
+    /// ```
+    ///
+    /// The default implementation of this method returns `true`. Data formats
+    /// may override this to `false` to request a compact form for types that
+    /// support one. Note that modifying this method to change a format from
+    /// human-readable to compact or vice versa should be regarded as a breaking
+    /// change, as a value serialized in human-readable mode is not required to
+    /// deserialize from the same data in compact mode.
+    #[inline]
+    fn is_human_readable(&self) -> bool { true }
 }
 
 ////////////////////////////////////////////////////////////////////////////////

serde/src/de/value.rs

@@ -733,7 +733,7 @@ where
     T: IntoDeserializer<'de, E>,
     E: de::Error,
 {
-    type Deserializer = SeqDeserializer<<Vec<T> as IntoIterator>::IntoIter, E>;
+    type Deserializer = SeqDeserializer<<Self as IntoIterator>::IntoIter, E>;
 
     fn into_deserializer(self) -> Self::Deserializer {
         SeqDeserializer::new(self.into_iter())
@@ -746,7 +746,7 @@ where
     T: IntoDeserializer<'de, E> + Eq + Ord,
     E: de::Error,
 {
-    type Deserializer = SeqDeserializer<<BTreeSet<T> as IntoIterator>::IntoIter, E>;
+    type Deserializer = SeqDeserializer<<Self as IntoIterator>::IntoIter, E>;
 
     fn into_deserializer(self) -> Self::Deserializer {
         SeqDeserializer::new(self.into_iter())
@@ -754,12 +754,13 @@ where
 }
 
 #[cfg(feature = "std")]
-impl<'de, T, E> IntoDeserializer<'de, E> for HashSet<T>
+impl<'de, T, S, E> IntoDeserializer<'de, E> for HashSet<T, S>
 where
     T: IntoDeserializer<'de, E> + Eq + Hash,
+    S: BuildHasher,
     E: de::Error,
 {
-    type Deserializer = SeqDeserializer<<HashSet<T> as IntoIterator>::IntoIter, E>;
+    type Deserializer = SeqDeserializer<<Self as IntoIterator>::IntoIter, E>;
 
     fn into_deserializer(self) -> Self::Deserializer {
         SeqDeserializer::new(self.into_iter())
@@ -1152,7 +1153,7 @@ where
     V: IntoDeserializer<'de, E>,
     E: de::Error,
 {
-    type Deserializer = MapDeserializer<'de, <BTreeMap<K, V> as IntoIterator>::IntoIter, E>;
+    type Deserializer = MapDeserializer<'de, <Self as IntoIterator>::IntoIter, E>;
 
     fn into_deserializer(self) -> Self::Deserializer {
         MapDeserializer::new(self.into_iter())
@@ -1160,13 +1161,14 @@ where
 }
 
 #[cfg(feature = "std")]
-impl<'de, K, V, E> IntoDeserializer<'de, E> for HashMap<K, V>
+impl<'de, K, V, S, E> IntoDeserializer<'de, E> for HashMap<K, V, S>
 where
     K: IntoDeserializer<'de, E> + Eq + Hash,
     V: IntoDeserializer<'de, E>,
+    S: BuildHasher,
     E: de::Error,
 {
-    type Deserializer = MapDeserializer<'de, <HashMap<K, V> as IntoIterator>::IntoIter, E>;
+    type Deserializer = MapDeserializer<'de, <Self as IntoIterator>::IntoIter, E>;
 
     fn into_deserializer(self) -> Self::Deserializer {
         MapDeserializer::new(self.into_iter())

serde/src/lib.rs

@@ -79,7 +79,7 @@
 ////////////////////////////////////////////////////////////////////////////////
 
 // Serde types in rustdoc of other crates get linked to here.
-#![doc(html_root_url = "https://docs.rs/serde/1.0.14")]
+#![doc(html_root_url = "https://docs.rs/serde/1.0.16")]
 
 // Support using Serde without the standard library!
 #![cfg_attr(not(feature = "std"), no_std)]

serde/src/private/de.rs

@@ -834,26 +834,43 @@ mod content {
         type Value = TaggedContent<'de, T>;
 
         fn expecting(&self, fmt: &mut fmt::Formatter) -> fmt::Result {
-            fmt.write_str("any value")
+            fmt.write_str("internally tagged enum")
         }
 
-        fn visit_map<V>(self, mut visitor: V) -> Result<Self::Value, V::Error>
+        fn visit_seq<S>(self, mut seq: S) -> Result<Self::Value, S::Error>
         where
-            V: MapAccess<'de>,
+            S: SeqAccess<'de>,
+        {
+            let tag = match try!(seq.next_element()) {
+                Some(tag) => tag,
+                None => {
+                    return Err(de::Error::missing_field(self.tag_name));
+                }
+            };
+            let rest = de::value::SeqAccessDeserializer::new(seq);
+            Ok(TaggedContent {
+                tag: tag,
+                content: try!(Content::deserialize(rest)),
+            })
+        }
+
+        fn visit_map<M>(self, mut map: M) -> Result<Self::Value, M::Error>
+        where
+            M: MapAccess<'de>,
         {
             let mut tag = None;
-            let mut vec = Vec::with_capacity(size_hint::cautious(visitor.size_hint()));
+            let mut vec = Vec::with_capacity(size_hint::cautious(map.size_hint()));
             while let Some(k) =
-                try!(visitor.next_key_seed(TagOrContentVisitor::new(self.tag_name))) {
+                try!(map.next_key_seed(TagOrContentVisitor::new(self.tag_name))) {
                 match k {
                     TagOrContent::Tag => {
                         if tag.is_some() {
                             return Err(de::Error::duplicate_field(self.tag_name));
                         }
-                        tag = Some(try!(visitor.next_value()));
+                        tag = Some(try!(map.next_value()));
                     }
                     TagOrContent::Content(k) => {
-                        let v = try!(visitor.next_value());
+                        let v = try!(map.next_value());
                         vec.push((k, v));
                     }
                 }
@@ -1802,9 +1819,16 @@ mod content {
             write!(formatter, "unit variant {}::{}", self.type_name, self.variant_name)
         }
 
-        fn visit_map<V>(self, _: V) -> Result<(), V::Error>
+        fn visit_seq<S>(self, _: S) -> Result<(), S::Error>
         where
-            V: MapAccess<'de>,
+            S: SeqAccess<'de>,
+        {
+            Ok(())
+        }
+
+        fn visit_map<M>(self, _: M) -> Result<(), M::Error>
+        where
+            M: MapAccess<'de>,
         {
             Ok(())
         }

serde/src/ser/impls.rs

@@ -506,9 +506,18 @@ impl Serialize for net::IpAddr {
     where
         S: Serializer,
     {
-        match *self {
-            net::IpAddr::V4(ref a) => a.serialize(serializer),
-            net::IpAddr::V6(ref a) => a.serialize(serializer),
+        if serializer.is_human_readable() {
+            match *self {
+                net::IpAddr::V4(ref a) => a.serialize(serializer),
+                net::IpAddr::V6(ref a) => a.serialize(serializer),
+            }
+        } else {
+            match *self {
+                net::IpAddr::V4(ref a) =>
+                    serializer.serialize_newtype_variant("IpAddr", 0, "V4", a),
+                net::IpAddr::V6(ref a) =>
+                    serializer.serialize_newtype_variant("IpAddr", 1, "V6", a),
+            }
         }
     }
 }
@@ -519,9 +528,13 @@ impl Serialize for net::Ipv4Addr {
     where
         S: Serializer,
     {
-        /// "101.102.103.104".len()
-        const MAX_LEN: usize = 15;
-        serialize_display_bounded_length!(self, MAX_LEN, serializer)
+        if serializer.is_human_readable() {
+            const MAX_LEN: usize = 15;
+            debug_assert_eq!(MAX_LEN, "101.102.103.104".len());
+            serialize_display_bounded_length!(self, MAX_LEN, serializer)
+        } else {
+            self.octets().serialize(serializer)
+        }
     }
 }
 
@@ -531,9 +544,13 @@ impl Serialize for net::Ipv6Addr {
     where
         S: Serializer,
     {
-        /// "1000:1002:1003:1004:1005:1006:1007:1008".len()
-        const MAX_LEN: usize = 39;
-        serialize_display_bounded_length!(self, MAX_LEN, serializer)
+        if serializer.is_human_readable() {
+            const MAX_LEN: usize = 39;
+            debug_assert_eq!(MAX_LEN, "1001:1002:1003:1004:1005:1006:1007:1008".len());
+            serialize_display_bounded_length!(self, MAX_LEN, serializer)
+        } else {
+            self.octets().serialize(serializer)
+        }
     }
 }
 
@@ -543,9 +560,18 @@ impl Serialize for net::SocketAddr {
     where
         S: Serializer,
     {
-        match *self {
-            net::SocketAddr::V4(ref addr) => addr.serialize(serializer),
-            net::SocketAddr::V6(ref addr) => addr.serialize(serializer),
+        if serializer.is_human_readable() {
+            match *self {
+                net::SocketAddr::V4(ref addr) => addr.serialize(serializer),
+                net::SocketAddr::V6(ref addr) => addr.serialize(serializer),
+            }
+        } else {
+            match *self {
+                net::SocketAddr::V4(ref addr) =>
+                    serializer.serialize_newtype_variant("SocketAddr", 0, "V4", addr),
+                net::SocketAddr::V6(ref addr) =>
+                    serializer.serialize_newtype_variant("SocketAddr", 1, "V6", addr),
+            }
         }
     }
 }
@@ -556,9 +582,13 @@ impl Serialize for net::SocketAddrV4 {
     where
         S: Serializer,
     {
-        /// "101.102.103.104:65000".len()
-        const MAX_LEN: usize = 21;
-        serialize_display_bounded_length!(self, MAX_LEN, serializer)
+        if serializer.is_human_readable() {
+            const MAX_LEN: usize = 21;
+            debug_assert_eq!(MAX_LEN, "101.102.103.104:65000".len());
+            serialize_display_bounded_length!(self, MAX_LEN, serializer)
+        } else {
+            (self.ip(), self.port()).serialize(serializer)
+        }
     }
 }
 
@@ -568,9 +598,13 @@ impl Serialize for net::SocketAddrV6 {
     where
         S: Serializer,
     {
-        /// "[1000:1002:1003:1004:1005:1006:1007:1008]:65000".len()
-        const MAX_LEN: usize = 47;
-        serialize_display_bounded_length!(self, MAX_LEN, serializer)
+        if serializer.is_human_readable() {
+            const MAX_LEN: usize = 47;
+            debug_assert_eq!(MAX_LEN, "[1001:1002:1003:1004:1005:1006:1007:1008]:65000".len());
+            serialize_display_bounded_length!(self, MAX_LEN, serializer)
+        } else {
+            (self.ip(), self.port()).serialize(serializer)
+        }
     }
 }
 

serde/src/ser/mod.rs

@@ -1363,6 +1363,56 @@ pub trait Serializer: Sized {
     fn collect_str<T: ?Sized>(self, value: &T) -> Result<Self::Ok, Self::Error>
     where
         T: Display;
+
+    /// Determine whether `Serialize` implementations should serialize in
+    /// human-readable form.
+    ///
+    /// Some types have a human-readable form that may be somewhat expensive to
+    /// construct, as well as a binary form that is compact and efficient.
+    /// Generally text-based formats like JSON and YAML will prefer to use the
+    /// human-readable one and binary formats like Bincode will prefer the
+    /// compact one.
+    ///
+    /// ```
+    /// # use std::fmt::{self, Display};
+    /// #
+    /// # struct Timestamp;
+    /// #
+    /// # impl Timestamp {
+    /// #     fn seconds_since_epoch(&self) -> u64 { unimplemented!() }
+    /// # }
+    /// #
+    /// # impl Display for Timestamp {
+    /// #     fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
+    /// #         unimplemented!()
+    /// #     }
+    /// # }
+    /// #
+    /// use serde::{Serialize, Serializer};
+    ///
+    /// impl Serialize for Timestamp {
+    ///     fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
+    ///         where S: Serializer
+    ///     {
+    ///         if serializer.is_human_readable() {
+    ///             // Serialize to a human-readable string "2015-05-15T17:01:00Z".
+    ///             self.to_string().serialize(serializer)
+    ///         } else {
+    ///             // Serialize to a compact binary representation.
+    ///             self.seconds_since_epoch().serialize(serializer)
+    ///         }
+    ///     }
+    /// }
+    /// ```
+    ///
+    /// The default implementation of this method returns `true`. Data formats
+    /// may override this to `false` to request a compact form for types that
+    /// support one. Note that modifying this method to change a format from
+    /// human-readable to compact or vice versa should be regarded as a breaking
+    /// change, as a value serialized in human-readable mode is not required to
+    /// deserialize from the same data in compact mode.
+    #[inline]
+    fn is_human_readable(&self) -> bool { true }
 }
 
 /// Returned from `Serializer::serialize_seq`.

serde_derive/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "serde_derive"
-version = "1.0.14" # remember to update html_root_url
+version = "1.0.16" # remember to update html_root_url
 authors = ["Erick Tryzelaar <erick.tryzelaar@gmail.com>", "David Tolnay <dtolnay@gmail.com>"]
 license = "MIT/Apache-2.0"
 description = "Macros 1.1 implementation of #[derive(Serialize, Deserialize)]"

serde_derive/src/de.rs

@@ -222,7 +222,7 @@ fn deserialize_body(cont: &Container, params: &Parameters) -> Fragment {
                 if fields.iter().any(|field| field.ident.is_none()) {
                     panic!("struct has unnamed fields");
                 }
-                deserialize_struct(None, params, fields, &cont.attrs, None)
+                deserialize_struct(None, params, fields, &cont.attrs, None, Untagged::No)
             }
             Body::Struct(Style::Tuple, ref fields) |
             Body::Struct(Style::Newtype, ref fields) => {
@@ -488,15 +488,20 @@ fn deserialize_newtype_struct(type_path: &Tokens, params: &Parameters, field: &F
     }
 }
 
+enum Untagged {
+    Yes,
+    No,
+}
+
 fn deserialize_struct(
     variant_ident: Option<&syn::Ident>,
     params: &Parameters,
     fields: &[Field],
     cattrs: &attr::Container,
     deserializer: Option<Tokens>,
+    untagged: Untagged,
 ) -> Fragment {
     let is_enum = variant_ident.is_some();
-    let is_untagged = deserializer.is_some();
 
     let this = &params.this;
     let (de_impl_generics, de_ty_generics, ty_generics, where_clause) = split_with_de_lifetime(params,);
@@ -559,18 +564,19 @@ fn deserialize_struct(
         quote!(mut __seq)
     };
 
-    let visit_seq = if is_untagged {
-        // untagged struct variants do not get a visit_seq method
-        None
-    } else {
-        Some(quote! {
-            #[inline]
-            fn visit_seq<__A>(self, #visitor_var: __A) -> _serde::export::Result<Self::Value, __A::Error>
-                where __A: _serde::de::SeqAccess<#delife>
-            {
-                #visit_seq
-            }
-        })
+    // untagged struct variants do not get a visit_seq method
+    let visit_seq = match untagged {
+        Untagged::Yes => None,
+        Untagged::No => {
+            Some(quote! {
+                #[inline]
+                fn visit_seq<__A>(self, #visitor_var: __A) -> _serde::export::Result<Self::Value, __A::Error>
+                    where __A: _serde::de::SeqAccess<#delife>
+                {
+                    #visit_seq
+                }
+            })
+        }
     };
 
     quote_block! {
@@ -1148,7 +1154,7 @@ fn deserialize_externally_tagged_variant(
             deserialize_tuple(Some(variant_ident), params, &variant.fields, cattrs, None)
         }
         Style::Struct => {
-            deserialize_struct(Some(variant_ident), params, &variant.fields, cattrs, None)
+            deserialize_struct(Some(variant_ident), params, &variant.fields, cattrs, None, Untagged::No)
         }
     }
 }
@@ -1175,8 +1181,23 @@ fn deserialize_internally_tagged_variant(
                 _serde::export::Ok(#this::#variant_ident)
             }
         }
-        Style::Newtype | Style::Struct => {
-            deserialize_untagged_variant(params, variant, cattrs, deserializer)
+        Style::Newtype => {
+            deserialize_untagged_newtype_variant(
+                variant_ident,
+                params,
+                &variant.fields[0],
+                deserializer,
+            )
+        }
+        Style::Struct => {
+            deserialize_struct(
+                Some(variant_ident),
+                params,
+                &variant.fields,
+                cattrs,
+                Some(deserializer),
+                Untagged::No,
+            )
         }
         Style::Tuple => unreachable!("checked in serde_derive_internals"),
     }
@@ -1238,6 +1259,7 @@ fn deserialize_untagged_variant(
                 &variant.fields,
                 cattrs,
                 Some(deserializer),
+                Untagged::Yes,
             )
         }
     }

serde_derive/src/lib.rs

@@ -16,7 +16,7 @@
 //!
 //! [https://serde.rs/derive.html]: https://serde.rs/derive.html
 
-#![doc(html_root_url = "https://docs.rs/serde_derive/1.0.14")]
+#![doc(html_root_url = "https://docs.rs/serde_derive/1.0.16")]
 
 #![cfg_attr(feature = "cargo-clippy", allow(too_many_arguments))]
 #![cfg_attr(feature = "cargo-clippy", allow(used_underscore_binding))]

serde_test/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "serde_test"
-version = "1.0.14" # remember to update html_root_url
+version = "1.0.16" # remember to update html_root_url
 authors = ["Erick Tryzelaar <erick.tryzelaar@gmail.com>", "David Tolnay <dtolnay@gmail.com>"]
 license = "MIT/Apache-2.0"
 description = "Token De/Serializer for testing De/Serialize implementations"

serde_test/src/assert.rs

@@ -47,8 +47,20 @@ pub fn assert_tokens<'de, T>(value: &T, tokens: &'de [Token])
 where
     T: Serialize + Deserialize<'de> + PartialEq + Debug,
 {
-    assert_ser_tokens(value, tokens);
-    assert_de_tokens(value, tokens);
+    assert_tokens_readable(value, tokens, None);
+}
+
+// Not public API
+#[doc(hidden)]
+/// Runs both `assert_ser_tokens` and `assert_de_tokens`.
+///
+/// See: `assert_tokens`
+pub fn assert_tokens_readable<'de, T>(value: &T, tokens: &'de [Token], human_readable: Option<bool>)
+where
+    T: Serialize + Deserialize<'de> + PartialEq + Debug,
+{
+    assert_ser_tokens_readable(value, tokens, human_readable);
+    assert_de_tokens_readable(value, tokens, human_readable);
 }
 
 /// Asserts that `value` serializes to the given `tokens`.
@@ -84,7 +96,19 @@ pub fn assert_ser_tokens<T>(value: &T, tokens: &[Token])
 where
     T: Serialize,
 {
-    let mut ser = Serializer::new(tokens);
+    assert_ser_tokens_readable(value, tokens, None)
+}
+
+// Not public API
+#[doc(hidden)]
+/// Asserts that `value` serializes to the given `tokens`.
+///
+/// See: `assert_ser_tokens`
+pub fn assert_ser_tokens_readable<T>(value: &T, tokens: &[Token], human_readable: Option<bool>)
+where
+    T: Serialize,
+{
+    let mut ser = Serializer::readable(tokens, human_readable);
     match value.serialize(&mut ser) {
         Ok(_) => {}
         Err(err) => panic!("value failed to serialize: {}", err),
@@ -183,7 +207,16 @@ pub fn assert_de_tokens<'de, T>(value: &T, tokens: &'de [Token])
 where
     T: Deserialize<'de> + PartialEq + Debug,
 {
-    let mut de = Deserializer::new(tokens);
+    assert_de_tokens_readable(value, tokens, None)
+}
+
+// Not public API
+#[doc(hidden)]
+pub fn assert_de_tokens_readable<'de, T>(value: &T, tokens: &'de [Token], human_readable: Option<bool>)
+where
+    T: Deserialize<'de> + PartialEq + Debug,
+{
+    let mut de = Deserializer::readable(tokens, human_readable);
     match T::deserialize(&mut de) {
         Ok(v) => assert_eq!(v, *value),
         Err(e) => panic!("tokens failed to deserialize: {}", e),

serde_test/src/de.rs

@@ -16,6 +16,7 @@ use token::Token;
 #[derive(Debug)]
 pub struct Deserializer<'de> {
     tokens: &'de [Token],
+    is_human_readable: Option<bool>,
 }
 
 macro_rules! assert_next_token {
@@ -48,7 +49,13 @@ macro_rules! end_of_tokens {
 
 impl<'de> Deserializer<'de> {
     pub fn new(tokens: &'de [Token]) -> Self {
-        Deserializer { tokens: tokens }
+        Deserializer::readable(tokens, None)
+    }
+
+    // Not public API
+    #[doc(hidden)]
+    pub fn readable(tokens: &'de [Token], is_human_readable: Option<bool>) -> Self {
+        Deserializer { tokens: tokens, is_human_readable: is_human_readable }
     }
 
     fn peek_token_opt(&self) -> Option<Token> {
@@ -364,6 +371,18 @@ impl<'de, 'a> de::Deserializer<'de> for &'a mut Deserializer<'de> {
             _ => self.deserialize_any(visitor),
         }
     }
+
+    fn is_human_readable(&self) -> bool {
+        match self.is_human_readable {
+            Some(is) => is,
+            None => {
+                panic!("There is no serde_test API currently for testing types \
+                        that have different human-readable and compact \
+                        representation. See \
+                        https://github.com/serde-rs/serde/issues/1065.");
+            }
+        }
+    }
 }
 
 //////////////////////////////////////////////////////////////////////////

serde_test/src/lib.rs

@@ -155,7 +155,7 @@
 //! # }
 //! ```
 
-#![doc(html_root_url = "https://docs.rs/serde_test/1.0.14")]
+#![doc(html_root_url = "https://docs.rs/serde_test/1.0.16")]
 
 #[macro_use]
 extern crate serde;
@@ -168,8 +168,12 @@ mod token;
 mod assert;
 
 pub use token::Token;
-pub use assert::{assert_tokens, assert_ser_tokens, assert_ser_tokens_error, assert_de_tokens,
-                 assert_de_tokens_error};
+pub use assert::{assert_tokens, assert_ser_tokens, assert_ser_tokens_error,
+                 assert_de_tokens, assert_de_tokens_error};
+
+// Not public API.
+#[doc(hidden)]
+pub use assert::{assert_tokens_readable, assert_de_tokens_readable, assert_ser_tokens_readable};
 
 // Not public API.
 #[doc(hidden)]

serde_test/src/ser.rs

@@ -15,12 +15,19 @@ use token::Token;
 #[derive(Debug)]
 pub struct Serializer<'a> {
     tokens: &'a [Token],
+    is_human_readable: Option<bool>,
 }
 
 impl<'a> Serializer<'a> {
     /// Creates the serializer.
     pub fn new(tokens: &'a [Token]) -> Self {
-        Serializer { tokens: tokens }
+        Serializer::readable(tokens, None)
+    }
+
+    // Not public API
+    #[doc(hidden)]
+    pub fn readable(tokens: &'a [Token], is_human_readable: Option<bool>) -> Self {
+        Serializer { tokens: tokens, is_human_readable: is_human_readable }
     }
 
     /// Pulls the next token off of the serializer, ignoring it.
@@ -282,6 +289,18 @@ impl<'s, 'a> ser::Serializer for &'s mut Serializer<'a> {
             Ok(Variant { ser: self, end: Token::StructVariantEnd })
         }
     }
+
+    fn is_human_readable(&self) -> bool {
+        match self.is_human_readable {
+            Some(is) => is,
+            None => {
+                panic!("There is no serde_test API currently for testing types \
+                        that have different human-readable and compact \
+                        representation. See \
+                        https://github.com/serde-rs/serde/issues/1065.");
+            }
+        }
+    }
 }
 
 pub struct Variant<'s, 'a: 's> {

test_suite/tests/macros/mod.rs

@@ -73,3 +73,29 @@ macro_rules! hashmap {
         }
     }
 }
+
+macro_rules! seq_impl {
+    (seq $first:expr,) => {
+        seq_impl!(seq $first)
+    };
+    ($first:expr,) => {
+        seq_impl!($first)
+    };
+    (seq $first:expr) => {
+        $first.into_iter()
+    };
+    ($first:expr) => {
+        Some($first).into_iter()
+    };
+    (seq $first:expr , $( $elem: tt)*) => {
+        $first.into_iter().chain(seq!( $($elem)* ))
+    };
+    ($first:expr , $($elem: tt)*) => {
+        Some($first).into_iter().chain(seq!( $($elem)* ))
+    }
+}
+macro_rules! seq {
+    ($($tt: tt)*) => {
+        seq_impl!($($tt)*).collect::<Vec<_>>()
+    };
+}

test_suite/tests/test_de.rs

@@ -28,7 +28,7 @@ extern crate fnv;
 use self::fnv::FnvHasher;
 
 extern crate serde_test;
-use self::serde_test::{Token, assert_de_tokens, assert_de_tokens_error};
+use self::serde_test::{Token, assert_de_tokens, assert_de_tokens_error, assert_de_tokens_readable};
 
 #[macro_use]
 mod macros;
@@ -109,25 +109,37 @@ enum EnumSkipAll {
 
 //////////////////////////////////////////////////////////////////////////
 
-macro_rules! declare_test {
-    ($name:ident { $($value:expr => $tokens:expr,)+ }) => {
-        #[test]
-        fn $name() {
-            $(
-                // Test ser/de roundtripping
-                assert_de_tokens(&$value, $tokens);
-
-                // Test that the tokens are ignorable
-                assert_de_tokens_ignore($tokens);
-            )+
-        }
-    }
-}
-
 macro_rules! declare_tests {
+    (
+        readable: $readable:tt
+        $($name:ident { $($value:expr => $tokens:expr,)+ })+
+    ) => {
+        $(
+            #[test]
+            fn $name() {
+                $(
+                    // Test ser/de roundtripping
+                    assert_de_tokens_readable(&$value, $tokens, Some($readable));
+
+                    // Test that the tokens are ignorable
+                    assert_de_tokens_ignore($tokens);
+                )+
+            }
+        )+
+    };
+
     ($($name:ident { $($value:expr => $tokens:expr,)+ })+) => {
         $(
-            declare_test!($name { $($value => $tokens,)+ });
+            #[test]
+            fn $name() {
+                $(
+                    // Test ser/de roundtripping
+                    assert_de_tokens(&$value, $tokens);
+
+                    // Test that the tokens are ignorable
+                    assert_de_tokens_ignore($tokens);
+                )+
+            }
         )+
     }
 }
@@ -725,17 +737,6 @@ declare_tests! {
             Token::SeqEnd,
         ],
     }
-    test_net_ipv4addr {
-        "1.2.3.4".parse::<net::Ipv4Addr>().unwrap() => &[Token::Str("1.2.3.4")],
-    }
-    test_net_ipv6addr {
-        "::1".parse::<net::Ipv6Addr>().unwrap() => &[Token::Str("::1")],
-    }
-    test_net_socketaddr {
-        "1.2.3.4:1234".parse::<net::SocketAddr>().unwrap() => &[Token::Str("1.2.3.4:1234")],
-        "1.2.3.4:1234".parse::<net::SocketAddrV4>().unwrap() => &[Token::Str("1.2.3.4:1234")],
-        "[::1]:1234".parse::<net::SocketAddrV6>().unwrap() => &[Token::Str("[::1]:1234")],
-    }
     test_path {
         Path::new("/usr/local/lib") => &[
             Token::BorrowedStr("/usr/local/lib"),
@@ -763,6 +764,97 @@ declare_tests! {
     }
 }
 
+declare_tests! {
+    readable: true
+    test_net_ipv4addr_readable {
+        "1.2.3.4".parse::<net::Ipv4Addr>().unwrap() => &[Token::Str("1.2.3.4")],
+    }
+    test_net_ipv6addr_readable {
+        "::1".parse::<net::Ipv6Addr>().unwrap() => &[Token::Str("::1")],
+    }
+    test_net_ipaddr_readable {
+        "1.2.3.4".parse::<net::IpAddr>().unwrap() => &[Token::Str("1.2.3.4")],
+    }
+    test_net_socketaddr_readable {
+        "1.2.3.4:1234".parse::<net::SocketAddr>().unwrap() => &[Token::Str("1.2.3.4:1234")],
+        "1.2.3.4:1234".parse::<net::SocketAddrV4>().unwrap() => &[Token::Str("1.2.3.4:1234")],
+        "[::1]:1234".parse::<net::SocketAddrV6>().unwrap() => &[Token::Str("[::1]:1234")],
+    }
+}
+
+declare_tests! {
+    readable: false
+    test_net_ipv4addr_compact {
+        net::Ipv4Addr::from(*b"1234") => &seq![
+            Token::Tuple { len: 4 },
+            seq b"1234".iter().map(|&b| Token::U8(b)),
+            Token::TupleEnd
+        ],
+    }
+    test_net_ipv6addr_compact {
+        net::Ipv6Addr::from(*b"1234567890123456") => &seq![
+            Token::Tuple { len: 4 },
+            seq b"1234567890123456".iter().map(|&b| Token::U8(b)),
+            Token::TupleEnd
+        ],
+    }
+    test_net_ipaddr_compact {
+        net::IpAddr::from(*b"1234") => &seq![
+            Token::NewtypeVariant { name: "IpAddr", variant: "V4" },
+
+            Token::Tuple { len: 4 },
+            seq b"1234".iter().map(|&b| Token::U8(b)),
+            Token::TupleEnd
+        ],
+    }
+    test_net_socketaddr_compact {
+        net::SocketAddr::from((*b"1234567890123456", 1234)) => &seq![
+            Token::NewtypeVariant { name: "SocketAddr", variant: "V6" },
+
+            Token::Tuple { len: 2 },
+
+            Token::Tuple { len: 16 },
+            seq b"1234567890123456".iter().map(|&b| Token::U8(b)),
+            Token::TupleEnd,
+
+            Token::U16(1234),
+            Token::TupleEnd
+        ],
+        net::SocketAddr::from((*b"1234", 1234)) => &seq![
+            Token::NewtypeVariant { name: "SocketAddr", variant: "V4" },
+
+            Token::Tuple { len: 2 },
+
+            Token::Tuple { len: 4 },
+            seq b"1234".iter().map(|&b| Token::U8(b)),
+            Token::TupleEnd,
+
+            Token::U16(1234),
+            Token::TupleEnd
+        ],
+        net::SocketAddrV4::new(net::Ipv4Addr::from(*b"1234"), 1234) => &seq![
+            Token::Tuple { len: 2 },
+
+            Token::Tuple { len: 4 },
+            seq b"1234".iter().map(|&b| Token::U8(b)),
+            Token::TupleEnd,
+
+            Token::U16(1234),
+            Token::TupleEnd
+        ],
+        net::SocketAddrV6::new(net::Ipv6Addr::from(*b"1234567890123456"), 1234, 0, 0) => &seq![
+            Token::Tuple { len: 2 },
+
+            Token::Tuple { len: 16 },
+            seq b"1234567890123456".iter().map(|&b| Token::U8(b)),
+            Token::TupleEnd,
+
+            Token::U16(1234),
+            Token::TupleEnd
+        ],
+    }
+}
+
 #[cfg(feature = "unstable")]
 declare_tests! {
     test_rc_dst {
@@ -836,15 +928,6 @@ fn test_cstr() {
     );
 }
 
-#[cfg(feature = "unstable")]
-#[test]
-fn test_net_ipaddr() {
-    assert_de_tokens(
-        &"1.2.3.4".parse::<net::IpAddr>().unwrap(),
-        &[Token::Str("1.2.3.4")],
-    );
-}
-
 #[cfg(feature = "unstable")]
 #[test]
 fn test_cstr_internal_null() {

test_suite/tests/test_macros.rs

@@ -591,11 +591,10 @@ fn test_internally_tagged_enum() {
     #[serde(tag = "type")]
     enum InternallyTagged {
         A { a: u8 },
-        B { b: u8 },
-        C,
-        D(BTreeMap<String, String>),
-        E(Newtype),
-        F(Struct),
+        B,
+        C(BTreeMap<String, String>),
+        D(Newtype),
+        E(Struct),
     }
 
     assert_tokens(
@@ -613,35 +612,62 @@ fn test_internally_tagged_enum() {
         ],
     );
 
-    assert_tokens(
-        &InternallyTagged::B { b: 2 },
+    assert_de_tokens(
+        &InternallyTagged::A { a: 1 },
         &[
-            Token::Struct { name: "InternallyTagged", len: 2 },
-
-            Token::Str("type"),
-            Token::Str("B"),
-
-            Token::Str("b"),
-            Token::U8(2),
-
-            Token::StructEnd,
+            Token::Seq { len: Some(2) },
+            Token::Str("A"),
+            Token::U8(1),
+            Token::SeqEnd,
         ],
     );
 
     assert_tokens(
-        &InternallyTagged::C,
+        &InternallyTagged::B,
         &[
             Token::Struct { name: "InternallyTagged", len: 1 },
 
             Token::Str("type"),
-            Token::Str("C"),
+            Token::Str("B"),
 
             Token::StructEnd,
         ],
     );
 
+    assert_de_tokens(
+        &InternallyTagged::B,
+        &[
+            Token::Seq { len: Some(1) },
+            Token::Str("B"),
+            Token::SeqEnd,
+        ],
+    );
+
     assert_tokens(
-        &InternallyTagged::D(BTreeMap::new()),
+        &InternallyTagged::C(BTreeMap::new()),
+        &[
+            Token::Map { len: Some(1) },
+
+            Token::Str("type"),
+            Token::Str("C"),
+
+            Token::MapEnd,
+        ],
+    );
+
+    assert_de_tokens_error::<InternallyTagged>(
+        &[
+            Token::Seq { len: Some(2) },
+            Token::Str("C"),
+            Token::Map { len: Some(0) },
+            Token::MapEnd,
+            Token::SeqEnd,
+        ],
+        "invalid type: sequence, expected a map",
+    );
+
+    assert_tokens(
+        &InternallyTagged::D(Newtype(BTreeMap::new())),
         &[
             Token::Map { len: Some(1) },
 
@@ -653,24 +679,12 @@ fn test_internally_tagged_enum() {
     );
 
     assert_tokens(
-        &InternallyTagged::E(Newtype(BTreeMap::new())),
-        &[
-            Token::Map { len: Some(1) },
-
-            Token::Str("type"),
-            Token::Str("E"),
-
-            Token::MapEnd,
-        ],
-    );
-
-    assert_tokens(
-        &InternallyTagged::F(Struct { f: 6 }),
+        &InternallyTagged::E(Struct { f: 6 }),
         &[
             Token::Struct { name: "Struct", len: 2 },
 
             Token::Str("type"),
-            Token::Str("F"),
+            Token::Str("E"),
 
             Token::Str("f"),
             Token::U8(6),
@@ -679,6 +693,16 @@ fn test_internally_tagged_enum() {
         ],
     );
 
+    assert_de_tokens(
+        &InternallyTagged::E(Struct { f: 6 }),
+        &[
+            Token::Seq { len: Some(2) },
+            Token::Str("E"),
+            Token::U8(6),
+            Token::SeqEnd,
+        ],
+    );
+
     assert_de_tokens_error::<InternallyTagged>(
         &[Token::Map { len: Some(0) }, Token::MapEnd],
         "missing field `type`",
@@ -693,7 +717,7 @@ fn test_internally_tagged_enum() {
 
             Token::MapEnd,
         ],
-        "unknown variant `Z`, expected one of `A`, `B`, `C`, `D`, `E`, `F`",
+        "unknown variant `Z`, expected one of `A`, `B`, `C`, `D`, `E`",
     );
 }
 

test_suite/tests/test_roundtrip.rs

@@ -0,0 +1,45 @@
+extern crate serde_test;
+use self::serde_test::{Token, assert_tokens_readable};
+
+use std::net;
+
+#[macro_use]
+#[allow(unused_macros)]
+mod macros;
+
+#[test]
+fn ip_addr_roundtrip() {
+
+    assert_tokens_readable(
+        &net::IpAddr::from(*b"1234"),
+        &seq![
+            Token::NewtypeVariant { name: "IpAddr", variant: "V4" },
+
+            Token::Tuple { len: 4 },
+            seq b"1234".iter().map(|&b| Token::U8(b)),
+            Token::TupleEnd,
+        ],
+        Some(false),
+    );
+}
+
+#[test]
+fn socked_addr_roundtrip() {
+
+    assert_tokens_readable(
+        &net::SocketAddr::from((*b"1234567890123456", 1234)),
+        &seq![
+            Token::NewtypeVariant { name: "SocketAddr", variant: "V6" },
+
+            Token::Tuple { len: 2 },
+
+            Token::Tuple { len: 16 },
+            seq b"1234567890123456".iter().map(|&b| Token::U8(b)),
+            Token::TupleEnd,
+
+            Token::U16(1234),
+            Token::TupleEnd,
+        ],
+        Some(false),
+    );
+}

test_suite/tests/test_ser.rs

@@ -23,7 +23,8 @@ use std::str;
 extern crate serde;
 
 extern crate serde_test;
-use self::serde_test::{Token, assert_ser_tokens, assert_ser_tokens_error};
+use self::serde_test::{Token, assert_ser_tokens, assert_ser_tokens_error,
+                       assert_ser_tokens_readable};
 
 extern crate fnv;
 use self::fnv::FnvHasher;
@@ -65,6 +66,20 @@ enum Enum {
 //////////////////////////////////////////////////////////////////////////
 
 macro_rules! declare_tests {
+    (
+        readable: $readable:tt
+        $($name:ident { $($value:expr => $tokens:expr,)+ })+
+    ) => {
+        $(
+            #[test]
+            fn $name() {
+                $(
+                    assert_ser_tokens_readable(&$value, $tokens, Some($readable));
+                )+
+            }
+        )+
+    };
+
     ($($name:ident { $($value:expr => $tokens:expr,)+ })+) => {
         $(
             #[test]
@@ -354,17 +369,6 @@ declare_tests! {
             Token::StructEnd,
         ],
     }
-    test_net_ipv4addr {
-        "1.2.3.4".parse::<net::Ipv4Addr>().unwrap() => &[Token::Str("1.2.3.4")],
-    }
-    test_net_ipv6addr {
-        "::1".parse::<net::Ipv6Addr>().unwrap() => &[Token::Str("::1")],
-    }
-    test_net_socketaddr {
-        "1.2.3.4:1234".parse::<net::SocketAddr>().unwrap() => &[Token::Str("1.2.3.4:1234")],
-        "1.2.3.4:1234".parse::<net::SocketAddrV4>().unwrap() => &[Token::Str("1.2.3.4:1234")],
-        "[::1]:1234".parse::<net::SocketAddrV6>().unwrap() => &[Token::Str("[::1]:1234")],
-    }
     test_path {
         Path::new("/usr/local/lib") => &[
             Token::Str("/usr/local/lib"),
@@ -397,6 +401,85 @@ declare_tests! {
     }
 }
 
+declare_tests! {
+    readable: true
+    test_net_ipv4addr_readable {
+        "1.2.3.4".parse::<net::Ipv4Addr>().unwrap() => &[Token::Str("1.2.3.4")],
+    }
+    test_net_ipv6addr_readable {
+        "::1".parse::<net::Ipv6Addr>().unwrap() => &[Token::Str("::1")],
+    }
+    test_net_ipaddr_readable {
+        "1.2.3.4".parse::<net::IpAddr>().unwrap() => &[Token::Str("1.2.3.4")],
+    }
+    test_net_socketaddr_readable {
+        "1.2.3.4:1234".parse::<net::SocketAddr>().unwrap() => &[Token::Str("1.2.3.4:1234")],
+        "1.2.3.4:1234".parse::<net::SocketAddrV4>().unwrap() => &[Token::Str("1.2.3.4:1234")],
+        "[::1]:1234".parse::<net::SocketAddrV6>().unwrap() => &[Token::Str("[::1]:1234")],
+    }
+}
+
+declare_tests! {
+    readable: false
+    test_net_ipv4addr_compact {
+        net::Ipv4Addr::from(*b"1234") => &seq![
+            Token::Tuple { len: 4 },
+            seq b"1234".iter().map(|&b| Token::U8(b)),
+            Token::TupleEnd,
+        ],
+    }
+    test_net_ipv6addr_compact {
+        net::Ipv6Addr::from(*b"1234567890123456") => &seq![
+            Token::Tuple { len: 16 },
+            seq b"1234567890123456".iter().map(|&b| Token::U8(b)),
+            Token::TupleEnd,
+        ],
+    }
+    test_net_ipaddr_compact {
+        net::IpAddr::from(*b"1234") => &seq![
+            Token::NewtypeVariant { name: "IpAddr", variant: "V4" },
+
+            Token::Tuple { len: 4 },
+            seq b"1234".iter().map(|&b| Token::U8(b)),
+            Token::TupleEnd,
+        ],
+    }
+    test_net_socketaddr_compact {
+        net::SocketAddr::from((*b"1234567890123456", 1234)) => &seq![
+            Token::NewtypeVariant { name: "SocketAddr", variant: "V6" },
+
+            Token::Tuple { len: 2 },
+
+            Token::Tuple { len: 16 },
+            seq b"1234567890123456".iter().map(|&b| Token::U8(b)),
+            Token::TupleEnd,
+
+            Token::U16(1234),
+            Token::TupleEnd,
+        ],
+        net::SocketAddrV4::new(net::Ipv4Addr::from(*b"1234"), 1234) => &seq![
+            Token::Tuple { len: 2 },
+
+            Token::Tuple { len: 4 },
+            seq b"1234".iter().map(|&b| Token::U8(b)),
+            Token::TupleEnd,
+
+            Token::U16(1234),
+            Token::TupleEnd,
+        ],
+        net::SocketAddrV6::new(net::Ipv6Addr::from(*b"1234567890123456"), 1234, 0, 0) => &seq![
+            Token::Tuple { len: 2 },
+
+            Token::Tuple { len: 16 },
+            seq b"1234567890123456".iter().map(|&b| Token::U8(b)),
+            Token::TupleEnd,
+
+            Token::U16(1234),
+            Token::TupleEnd,
+        ],
+    }
+}
+
 // Serde's implementation is not unstable, but the constructors are.
 #[cfg(feature = "unstable")]
 declare_tests! {
@@ -422,15 +505,6 @@ declare_tests! {
     }
 }
 
-#[cfg(feature = "unstable")]
-#[test]
-fn test_net_ipaddr() {
-    assert_ser_tokens(
-        &"1.2.3.4".parse::<net::IpAddr>().unwrap(),
-        &[Token::Str("1.2.3.4")],
-    );
-}
-
 #[test]
 #[cfg(unix)]
 fn test_cannot_serialize_paths() {