Release 1.0.35

impl Serialize and Deserialize for std::num::NonZero*

appveyor.yml

@@ -5,7 +5,7 @@ environment:
 
 install:
   # Install rust, x86_64-pc-windows-msvc host
-  - appveyor DownloadFile https://win.rustup.rs/ -FileName rustup-init.exe
+  - curl -sSf -o rustup-init.exe https://win.rustup.rs/
   - rustup-init.exe -y --default-host x86_64-pc-windows-msvc --default-toolchain %APPVEYOR_RUST_CHANNEL%
   - set PATH=C:\msys64\usr\bin;%PATH%;C:\Users\appveyor\.cargo\bin
   - rustc -vV

serde/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "serde"
-version = "1.0.25" # remember to update html_root_url
+version = "1.0.35" # 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/from_primitive.rs

@@ -10,7 +10,7 @@ use lib::*;
 
 macro_rules! int_to_int {
     ($dst:ident, $n:ident) => (
-        if $dst::MIN as i64 <= $n as i64 && $n as i64 <= $dst::MAX as i64 {
+        if $dst::min_value() as i64 <= $n as i64 && $n as i64 <= $dst::max_value() as i64 {
             Some($n as $dst)
         } else {
             None
@@ -20,7 +20,7 @@ macro_rules! int_to_int {
 
 macro_rules! int_to_uint {
     ($dst:ident, $n:ident) => (
-        if 0 <= $n && $n as u64 <= $dst::MAX as u64 {
+        if 0 <= $n && $n as u64 <= $dst::max_value() as u64 {
             Some($n as $dst)
         } else {
             None
@@ -30,7 +30,7 @@ macro_rules! int_to_uint {
 
 macro_rules! uint_to {
     ($dst:ident, $n:ident) => (
-        if $n as u64 <= $dst::MAX as u64 {
+        if $n as u64 <= $dst::max_value() as u64 {
             Some($n as $dst)
         } else {
             None

serde/src/de/impls.rs

@@ -548,11 +548,11 @@ where
 
 ////////////////////////////////////////////////////////////////////////////////
 
-struct PhantomDataVisitor<T> {
+struct PhantomDataVisitor<T: ?Sized> {
     marker: PhantomData<T>,
 }
 
-impl<'de, T> Visitor<'de> for PhantomDataVisitor<T> {
+impl<'de, T: ?Sized> Visitor<'de> for PhantomDataVisitor<T> {
     type Value = PhantomData<T>;
 
     fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
@@ -568,7 +568,7 @@ impl<'de, T> Visitor<'de> for PhantomDataVisitor<T> {
     }
 }
 
-impl<'de, T> Deserialize<'de> for PhantomData<T> {
+impl<'de, T: ?Sized> Deserialize<'de> for PhantomData<T> {
     fn deserialize<D>(deserializer: D) -> Result<PhantomData<T>, D::Error>
     where
         D: Deserializer<'de>,
@@ -1918,6 +1918,7 @@ where
 ////////////////////////////////////////////////////////////////////////////////
 
 #[cfg(feature = "unstable")]
+#[allow(deprecated)]
 impl<'de, T> Deserialize<'de> for NonZero<T>
 where
     T: Deserialize<'de> + Zeroable,
@@ -1934,6 +1935,36 @@ where
     }
 }
 
+macro_rules! nonzero_integers {
+    ( $( $T: ty, )+ ) => {
+        $(
+            #[cfg(feature = "unstable")]
+            impl<'de> Deserialize<'de> for $T {
+                fn deserialize<D>(deserializer: D) -> Result<$T, D::Error>
+                where
+                    D: Deserializer<'de>,
+                {
+                    let value = try!(Deserialize::deserialize(deserializer));
+                    match <$T>::new(value) {
+                        Some(nonzero) => Ok(nonzero),
+                        None => Err(Error::custom("expected a non-zero value")),
+                    }
+                }
+            }
+        )+
+    };
+}
+
+nonzero_integers! {
+    // Not including signed NonZeroI* since they might be removed
+    NonZeroU8,
+    NonZeroU16,
+    NonZeroU32,
+    NonZeroU64,
+    // FIXME: https://github.com/serde-rs/serde/issues/1136 NonZeroU128,
+    NonZeroUsize,
+}
+
 ////////////////////////////////////////////////////////////////////////////////
 
 impl<'de, T, E> Deserialize<'de> for Result<T, E>

serde/src/de/mod.rs

@@ -98,7 +98,8 @@
 //!    - Path
 //!    - PathBuf
 //!    - Range\<T\>
-//!    - NonZero\<T\> (unstable)
+//!    - NonZero\<T\> (unstable, deprecated)
+//!    - num::NonZero* (unstable)
 //!  - **Net types**:
 //!    - IpAddr
 //!    - Ipv4Addr
@@ -513,7 +514,7 @@ pub trait Deserialize<'de>: Sized {
     /// have been overwritten. Although whatever state that is will be
     /// memory-safe.
     ///
-    /// This is generally useful when repeateadly deserializing values that
+    /// This is generally useful when repeatedly deserializing values that
     /// are processed one at a time, where the value of `self` doesn't matter
     /// when the next deserialization occurs.
     ///

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/1.0.25")]
+#![doc(html_root_url = "https://docs.rs/serde/1.0.35")]
 // Support using Serde without the standard library!
 #![cfg_attr(not(feature = "std"), no_std)]
 // Unstable functionality only if the user asks for it. For tracking and
@@ -92,8 +92,8 @@
 // Whitelisted clippy lints
 #![cfg_attr(feature = "cargo-clippy",
             allow(cast_lossless, const_static_lifetime, doc_markdown, linkedlist,
-                  needless_pass_by_value, type_complexity, unreadable_literal,
-                  zero_prefixed_literal))]
+                  needless_pass_by_value, redundant_field_names, type_complexity,
+                  unreadable_literal, zero_prefixed_literal))]
 // Whitelisted clippy_pedantic lints
 #![cfg_attr(feature = "cargo-clippy", allow(
 // integer and float ser/de requires these sorts of casts
@@ -104,6 +104,7 @@
 // simplifies some macros
     invalid_upcast_comparisons,
 // things are often more readable this way
+    decimal_literal_representation,
     option_unwrap_used,
     result_unwrap_used,
     shadow_reuse,
@@ -111,7 +112,9 @@
     stutter,
     use_self,
 // not practical
+    many_single_char_names,
     missing_docs_in_private_items,
+    similar_names,
 // alternative is not stable
     empty_enum,
     use_debug,
@@ -208,7 +211,11 @@ mod lib {
     pub use std::sync::{Mutex, RwLock};
 
     #[cfg(feature = "unstable")]
+    #[allow(deprecated)]
     pub use core::nonzero::{NonZero, Zeroable};
+
+    #[cfg(feature = "unstable")]
+    pub use core::num::{NonZeroU8, NonZeroU16, NonZeroU32, NonZeroU64, NonZeroUsize};
 }
 
 ////////////////////////////////////////////////////////////////////////////////

serde/src/private/de.rs

@@ -11,13 +11,13 @@ use lib::*;
 use de::{Deserialize, DeserializeSeed, Deserializer, Error, IntoDeserializer, Visitor};
 
 #[cfg(any(feature = "std", feature = "alloc"))]
-use de::Unexpected;
+use de::{Unexpected, MapAccess};
 
 #[cfg(any(feature = "std", feature = "alloc"))]
 pub use self::content::{Content, ContentDeserializer, ContentRefDeserializer,
                         InternallyTaggedUnitVisitor, TagContentOtherField,
                         TagContentOtherFieldVisitor, TagOrContentField, TagOrContentFieldVisitor,
-                        TaggedContentVisitor, UntaggedUnitVisitor};
+                        TaggedContentVisitor, UntaggedUnitVisitor, EnumDeserializer};
 
 /// If the missing field is of type `Option<T>` then treat is as `None`,
 /// otherwise it is an error.
@@ -188,7 +188,7 @@ where
         }
     }
 
-    deserializer.deserialize_str(CowBytesVisitor)
+    deserializer.deserialize_bytes(CowBytesVisitor)
 }
 
 pub mod size_hint {
@@ -269,6 +269,14 @@ mod content {
     }
 
     impl<'de> Content<'de> {
+        pub fn as_str(&self) -> Option<&str> {
+            match *self {
+                Content::Str(x) => Some(x),
+                Content::String(ref x) => Some(x),
+                _ => None,
+            }
+        }
+
         fn unexpected(&self) -> Unexpected {
             match *self {
                 Content::Bool(b) => Unexpected::Bool(b),
@@ -1118,11 +1126,7 @@ mod content {
                 }
             };
 
-            visitor.visit_enum(EnumDeserializer {
-                variant: variant,
-                value: value,
-                err: PhantomData,
-            })
+            visitor.visit_enum(EnumDeserializer::new(variant, value))
         }
 
         fn deserialize_unit_struct<V>(
@@ -1170,7 +1174,7 @@ mod content {
         }
     }
 
-    struct EnumDeserializer<'de, E>
+    pub struct EnumDeserializer<'de, E>
     where
         E: de::Error,
     {
@@ -1179,6 +1183,18 @@ mod content {
         err: PhantomData<E>,
     }
 
+    impl<'de, E> EnumDeserializer<'de, E>
+        where E: de::Error
+    {
+        pub fn new(variant: Content<'de>, value: Option<Content<'de>>) -> EnumDeserializer<'de, E> {
+            EnumDeserializer {
+                variant: variant,
+                value: value,
+                err: PhantomData,
+            }
+        }
+    }
+
     impl<'de, E> de::EnumAccess<'de> for EnumDeserializer<'de, E>
     where
         E: de::Error,
@@ -1199,7 +1215,7 @@ mod content {
         }
     }
 
-    struct VariantDeserializer<'de, E>
+    pub struct VariantDeserializer<'de, E>
     where
         E: de::Error,
     {
@@ -2062,3 +2078,162 @@ where
         T::deserialize_in_place(deserializer, self.0)
     }
 }
+
+#[cfg(any(feature = "std", feature = "alloc"))]
+pub struct FlatMapDeserializer<'a, 'de: 'a, E>(
+    pub &'a mut Vec<Option<(Content<'de>, Content<'de>)>>,
+    pub PhantomData<E>
+);
+
+#[cfg(any(feature = "std", feature = "alloc"))]
+impl<'a, 'de, E> Deserializer<'de> for FlatMapDeserializer<'a, 'de, E>
+    where E: Error
+{
+    type Error = E;
+
+    fn deserialize_any<V>(self, _: V) -> Result<V::Value, Self::Error>
+    where
+        V: Visitor<'de>,
+    {
+        Err(Error::custom("can only flatten structs and maps"))
+    }
+
+    fn deserialize_enum<V>(
+        self,
+        name: &'static str,
+        variants: &'static [&'static str],
+        visitor: V
+    ) -> Result<V::Value, Self::Error>
+    where
+        V: Visitor<'de>,
+    {
+        for item in self.0.iter_mut() {
+            // items in the vector are nulled out when used.  So we can only use
+            // an item if it's still filled in and if the field is one we care
+            // about.
+            let use_item = match *item {
+                None => false,
+                Some((ref c, _)) => c.as_str().map_or(false, |x| variants.contains(&x))
+            };
+
+            if use_item {
+                let (key, value) = item.take().unwrap();
+                return visitor.visit_enum(EnumDeserializer::new(
+                    key,
+                    Some(value)
+                ));
+            }
+        }
+
+        Err(Error::custom(format_args!(
+            "no variant of enum {} not found in flattened data",
+            name
+        )))
+    }
+
+    fn deserialize_map<V>(self, visitor: V) -> Result<V::Value, Self::Error>
+    where
+        V: Visitor<'de>,
+    {
+        visitor.visit_map(FlatMapAccess::new(self.0.iter_mut(), None))
+    }
+
+    fn deserialize_struct<V>(
+        self,
+        _: &'static str,
+        fields: &'static [&'static str],
+        visitor: V
+    ) -> Result<V::Value, Self::Error>
+    where
+        V: Visitor<'de>,
+    {
+        visitor.visit_map(FlatMapAccess::new(self.0.iter_mut(), Some(fields)))
+    }
+
+    fn deserialize_newtype_struct<V>(
+        self,
+        _name: &str,
+        visitor: V,
+    ) -> Result<V::Value, Self::Error>
+    where
+        V: Visitor<'de>,
+    {
+        visitor.visit_newtype_struct(self)
+    }
+
+    forward_to_deserialize_any! {
+        bool i8 i16 i32 i64 u8 u16 u32 u64 f32 f64 char str string bytes
+        byte_buf option unit unit_struct seq tuple tuple_struct identifier
+        ignored_any
+    }
+}
+
+#[cfg(any(feature = "std", feature = "alloc"))]
+pub struct FlatMapAccess<'a, 'de: 'a, E> {
+    iter: slice::IterMut<'a, Option<(Content<'de>, Content<'de>)>>,
+    pending_content: Option<Content<'de>>,
+    fields: Option<&'static [&'static str]>,
+    _marker: PhantomData<E>,
+}
+
+#[cfg(any(feature = "std", feature = "alloc"))]
+impl<'a, 'de, E> FlatMapAccess<'a, 'de, E> {
+    fn new(
+        iter: slice::IterMut<'a, Option<(Content<'de>, Content<'de>)>>,
+        fields: Option<&'static [&'static str]>
+    ) -> FlatMapAccess<'a, 'de, E> {
+        FlatMapAccess {
+            iter: iter,
+            pending_content: None,
+            fields: fields,
+            _marker: PhantomData,
+        }
+    }
+}
+
+#[cfg(any(feature = "std", feature = "alloc"))]
+impl<'a, 'de, E> MapAccess<'de> for FlatMapAccess<'a, 'de, E>
+    where E: Error
+{
+    type Error = E;
+
+    fn next_key_seed<T>(&mut self, seed: T) -> Result<Option<T::Value>, Self::Error>
+    where
+        T: DeserializeSeed<'de>,
+    {
+        while let Some(item) = self.iter.next() {
+            // items in the vector are nulled out when used.  So we can only use
+            // an item if it's still filled in and if the field is one we care
+            // about.  In case we do not know which fields we want, we take them all.
+            let use_item = match *item {
+                None => false,
+                Some((ref c, _)) => {
+                    c.as_str().map_or(self.fields.is_none(), |key| {
+                        match self.fields {
+                            None => true,
+                            Some(fields) if fields.contains(&key) => true,
+                            _ => false
+                        }
+                    })
+                }
+            };
+
+            if use_item {
+                let (key, content) = item.take().unwrap();
+                self.pending_content = Some(content);
+                return seed.deserialize(ContentDeserializer::new(key)).map(Some);
+            }
+        }
+        Ok(None)
+    }
+
+    fn next_value_seed<T>(&mut self, seed: T) -> Result<T::Value, Self::Error>
+    where
+        T: DeserializeSeed<'de>,
+    {
+        match self.pending_content.take() {
+            Some(value) => seed.deserialize(ContentDeserializer::new(value)),
+            None => Err(Error::custom("value is missing")),
+        }
+    }
+}

serde/src/private/ser.rs

@@ -11,7 +11,12 @@ use lib::*;
 use ser::{self, Impossible, Serialize, SerializeMap, SerializeStruct, Serializer};
 
 #[cfg(any(feature = "std", feature = "alloc"))]
-use self::content::{SerializeStructVariantAsMapValue, SerializeTupleVariantAsMapValue};
+use self::content::{
+    SerializeStructVariantAsMapValue,
+    SerializeTupleVariantAsMapValue,
+    ContentSerializer,
+    Content,
+};
 
 /// Used to check that serde(getter) attributes return the expected type.
 /// Not public API.
@@ -58,10 +63,11 @@ enum Unsupported {
     ByteArray,
     Optional,
     Unit,
+    #[cfg(any(feature = "std", feature = "alloc"))]
+    UnitStruct,
     Sequence,
     Tuple,
     TupleStruct,
-    #[cfg(not(any(feature = "std", feature = "alloc")))]
     Enum,
 }
 
@@ -76,10 +82,11 @@ impl Display for Unsupported {
             Unsupported::ByteArray => formatter.write_str("a byte array"),
             Unsupported::Optional => formatter.write_str("an optional"),
             Unsupported::Unit => formatter.write_str("unit"),
+            #[cfg(any(feature = "std", feature = "alloc"))]
+            Unsupported::UnitStruct => formatter.write_str("unit struct"),
             Unsupported::Sequence => formatter.write_str("a sequence"),
             Unsupported::Tuple => formatter.write_str("a tuple"),
             Unsupported::TupleStruct => formatter.write_str("a tuple struct"),
-            #[cfg(not(any(feature = "std", feature = "alloc")))]
             Unsupported::Enum => formatter.write_str("an enum"),
         }
     }
@@ -459,7 +466,7 @@ mod content {
     }
 
     #[derive(Debug)]
-    enum Content {
+    pub enum Content {
         Bool(bool),
 
         U8(u8),
@@ -584,12 +591,12 @@ mod content {
         }
     }
 
-    struct ContentSerializer<E> {
+    pub struct ContentSerializer<E> {
         error: PhantomData<E>,
     }
 
     impl<E> ContentSerializer<E> {
-        fn new() -> Self {
+        pub fn new() -> Self {
             ContentSerializer { error: PhantomData }
         }
     }
@@ -804,7 +811,7 @@ mod content {
         }
     }
 
-    struct SerializeSeq<E> {
+    pub struct SerializeSeq<E> {
         elements: Vec<Content>,
         error: PhantomData<E>,
     }
@@ -830,7 +837,7 @@ mod content {
         }
     }
 
-    struct SerializeTuple<E> {
+    pub struct SerializeTuple<E> {
         elements: Vec<Content>,
         error: PhantomData<E>,
     }
@@ -856,7 +863,7 @@ mod content {
         }
     }
 
-    struct SerializeTupleStruct<E> {
+    pub struct SerializeTupleStruct<E> {
         name: &'static str,
         fields: Vec<Content>,
         error: PhantomData<E>,
@@ -883,7 +890,7 @@ mod content {
         }
     }
 
-    struct SerializeTupleVariant<E> {
+    pub struct SerializeTupleVariant<E> {
         name: &'static str,
         variant_index: u32,
         variant: &'static str,
@@ -917,7 +924,7 @@ mod content {
         }
     }
 
-    struct SerializeMap<E> {
+    pub struct SerializeMap<E> {
         entries: Vec<(Content, Content)>,
         key: Option<Content>,
         error: PhantomData<E>,
@@ -967,7 +974,7 @@ mod content {
         }
     }
 
-    struct SerializeStruct<E> {
+    pub struct SerializeStruct<E> {
         name: &'static str,
         fields: Vec<(&'static str, Content)>,
         error: PhantomData<E>,
@@ -994,7 +1001,7 @@ mod content {
         }
     }
 
-    struct SerializeStructVariant<E> {
+    pub struct SerializeStructVariant<E> {
         name: &'static str,
         variant_index: u32,
         variant: &'static str,
@@ -1028,3 +1035,283 @@ mod content {
         }
     }
 }
+
+#[cfg(any(feature = "std", feature = "alloc"))]
+pub struct FlatMapSerializer<'a, M: 'a>(pub &'a mut M);
+
+#[cfg(any(feature = "std", feature = "alloc"))]
+impl<'a, M> FlatMapSerializer<'a, M>
+where
+    M: SerializeMap + 'a
+{
+    fn bad_type(self, what: Unsupported) -> M::Error {
+        ser::Error::custom(format_args!("can only flatten structs and maps (got {})", what))
+    }
+}
+
+#[cfg(any(feature = "std", feature = "alloc"))]
+impl<'a, M> Serializer for FlatMapSerializer<'a, M>
+    where M: SerializeMap + 'a
+{
+    type Ok = ();
+    type Error = M::Error;
+
+    type SerializeSeq = Impossible<Self::Ok, M::Error>;
+    type SerializeTuple = Impossible<Self::Ok, M::Error>;
+    type SerializeTupleStruct = Impossible<Self::Ok, M::Error>;
+    type SerializeMap = FlatMapSerializeMap<'a, M>;
+    type SerializeStruct = FlatMapSerializeStruct<'a, M>;
+    type SerializeTupleVariant = Impossible<Self::Ok, M::Error>;
+    type SerializeStructVariant = FlatMapSerializeStructVariantAsMapValue<'a, M>;
+
+    fn serialize_bool(self, _: bool) -> Result<Self::Ok, Self::Error> {
+        Err(self.bad_type(Unsupported::Boolean))
+    }
+
+    fn serialize_i8(self, _: i8) -> Result<Self::Ok, Self::Error> {
+        Err(self.bad_type(Unsupported::Integer))
+    }
+
+    fn serialize_i16(self, _: i16) -> Result<Self::Ok, Self::Error> {
+        Err(self.bad_type(Unsupported::Integer))
+    }
+
+    fn serialize_i32(self, _: i32) -> Result<Self::Ok, Self::Error> {
+        Err(self.bad_type(Unsupported::Integer))
+    }
+
+    fn serialize_i64(self, _: i64) -> Result<Self::Ok, Self::Error> {
+        Err(self.bad_type(Unsupported::Integer))
+    }
+
+    fn serialize_u8(self, _: u8) -> Result<Self::Ok, Self::Error> {
+        Err(self.bad_type(Unsupported::Integer))
+    }
+
+    fn serialize_u16(self, _: u16) -> Result<Self::Ok, Self::Error> {
+        Err(self.bad_type(Unsupported::Integer))
+    }
+
+    fn serialize_u32(self, _: u32) -> Result<Self::Ok, Self::Error> {
+        Err(self.bad_type(Unsupported::Integer))
+    }
+
+    fn serialize_u64(self, _: u64) -> Result<Self::Ok, Self::Error> {
+        Err(self.bad_type(Unsupported::Integer))
+    }
+
+    fn serialize_f32(self, _: f32) -> Result<Self::Ok, Self::Error> {
+        Err(self.bad_type(Unsupported::Float))
+    }
+
+    fn serialize_f64(self, _: f64) -> Result<Self::Ok, Self::Error> {
+        Err(self.bad_type(Unsupported::Float))
+    }
+
+    fn serialize_char(self, _: char) -> Result<Self::Ok, Self::Error> {
+        Err(self.bad_type(Unsupported::Char))
+    }
+
+    fn serialize_str(self, _: &str) -> Result<Self::Ok, Self::Error> {
+        Err(self.bad_type(Unsupported::String))
+    }
+
+    fn serialize_bytes(self, _: &[u8]) -> Result<Self::Ok, Self::Error> {
+        Err(self.bad_type(Unsupported::ByteArray))
+    }
+
+    fn serialize_none(self) -> Result<Self::Ok, Self::Error> {
+        Err(self.bad_type(Unsupported::Optional))
+    }
+
+    fn serialize_some<T: ?Sized>(self, _: &T) -> Result<Self::Ok, Self::Error>
+    where
+        T: Serialize,
+    {
+        Err(self.bad_type(Unsupported::Optional))
+    }
+
+    fn serialize_unit(self) -> Result<Self::Ok, Self::Error> {
+        Err(self.bad_type(Unsupported::Unit))
+    }
+
+    fn serialize_unit_struct(self, _: &'static str) -> Result<Self::Ok, Self::Error> {
+        Err(self.bad_type(Unsupported::UnitStruct))
+    }
+
+    fn serialize_unit_variant(
+        self,
+        _: &'static str,
+        _: u32,
+        _: &'static str,
+    ) -> Result<Self::Ok, Self::Error> {
+        Err(self.bad_type(Unsupported::Enum))
+    }
+
+    fn serialize_newtype_struct<T: ?Sized>(
+        self,
+        _: &'static str,
+        value: &T,
+    ) -> Result<Self::Ok, Self::Error>
+    where
+        T: Serialize,
+    {
+        value.serialize(self)
+    }
+
+    fn serialize_newtype_variant<T: ?Sized>(
+        self,
+        _: &'static str,
+        _: u32,
+        variant: &'static str,
+        value: &T,
+    ) -> Result<Self::Ok, Self::Error>
+    where
+        T: Serialize,
+    {
+        try!(self.0.serialize_key(variant));
+        self.0.serialize_value(value)
+    }
+
+    fn serialize_seq(self, _: Option<usize>) -> Result<Self::SerializeSeq, Self::Error> {
+        Err(self.bad_type(Unsupported::Sequence))
+    }
+
+    fn serialize_tuple(self, _: usize) -> Result<Self::SerializeTuple, Self::Error> {
+        Err(self.bad_type(Unsupported::Tuple))
+    }
+
+    fn serialize_tuple_struct(
+        self,
+        _: &'static str,
+        _: usize,
+    ) -> Result<Self::SerializeTupleStruct, Self::Error> {
+        Err(self.bad_type(Unsupported::TupleStruct))
+    }
+
+    fn serialize_tuple_variant(
+        self,
+        _: &'static str,
+        _: u32,
+        _: &'static str,
+        _: usize,
+    ) -> Result<Self::SerializeTupleVariant, Self::Error> {
+        Err(self.bad_type(Unsupported::Enum))
+    }
+
+    fn serialize_map(self, _: Option<usize>) -> Result<Self::SerializeMap, Self::Error> {
+        Ok(FlatMapSerializeMap(self.0))
+    }
+
+    fn serialize_struct(
+        self,
+        _: &'static str,
+        _: usize,
+    ) -> Result<Self::SerializeStruct, Self::Error> {
+        Ok(FlatMapSerializeStruct(self.0))
+    }
+
+    fn serialize_struct_variant(
+        self,
+        _: &'static str,
+        _: u32,
+        inner_variant: &'static str,
+        _: usize,
+    ) -> Result<Self::SerializeStructVariant, Self::Error> {
+        try!(self.0.serialize_key(inner_variant));
+        Ok(FlatMapSerializeStructVariantAsMapValue::new(self.0, inner_variant))
+    }
+}
+
+#[cfg(any(feature = "std", feature = "alloc"))]
+pub struct FlatMapSerializeMap<'a, M: 'a>(&'a mut M);
+
+#[cfg(any(feature = "std", feature = "alloc"))]
+impl<'a, M> ser::SerializeMap for FlatMapSerializeMap<'a, M>
+    where M: SerializeMap + 'a
+{
+    type Ok = ();
+    type Error = M::Error;
+
+    fn serialize_key<T: ?Sized>(&mut self, key: &T) -> Result<(), Self::Error>
+    where
+        T: Serialize,
+    {
+        self.0.serialize_key(key)
+    }
+
+    fn serialize_value<T: ?Sized>(&mut self, value: &T) -> Result<(), Self::Error>
+    where
+        T: Serialize,
+    {
+        self.0.serialize_value(value)
+    }
+
+    fn end(self) -> Result<(), Self::Error> {
+        Ok(())
+    }
+}
+
+#[cfg(any(feature = "std", feature = "alloc"))]
+pub struct FlatMapSerializeStruct<'a, M: 'a>(&'a mut M);
+
+#[cfg(any(feature = "std", feature = "alloc"))]
+impl<'a, M> ser::SerializeStruct for FlatMapSerializeStruct<'a, M>
+    where M: SerializeMap + 'a
+{
+    type Ok = ();
+    type Error = M::Error;
+
+    fn serialize_field<T: ?Sized>(&mut self, key: &'static str, value: &T) -> Result<(), Self::Error>
+    where
+        T: Serialize,
+    {
+        self.0.serialize_entry(key, value)
+    }
+
+    fn end(self) -> Result<(), Self::Error> {
+        Ok(())
+    }
+}
+
+#[cfg(any(feature = "std", feature = "alloc"))]
+pub struct FlatMapSerializeStructVariantAsMapValue<'a, M: 'a> {
+    map: &'a mut M,
+    name: &'static str,
+    fields: Vec<(&'static str, Content)>,
+}
+
+#[cfg(any(feature = "std", feature = "alloc"))]
+impl<'a, M> FlatMapSerializeStructVariantAsMapValue<'a, M>
+    where M: SerializeMap + 'a
+{
+    fn new(map: &'a mut M, name: &'static str) -> FlatMapSerializeStructVariantAsMapValue<'a, M> {
+        FlatMapSerializeStructVariantAsMapValue {
+            map: map,
+            name: name,
+            fields: Vec::new(),
+        }
+    }
+}
+
+#[cfg(any(feature = "std", feature = "alloc"))]
+impl<'a, M> ser::SerializeStructVariant for FlatMapSerializeStructVariantAsMapValue<'a, M>
+    where M: SerializeMap + 'a
+{
+    type Ok = ();
+    type Error = M::Error;
+
+    fn serialize_field<T: ?Sized>(&mut self, key: &'static str, value: &T) -> Result<(), Self::Error>
+    where
+        T: Serialize,
+    {
+        let value = try!(value.serialize(ContentSerializer::<M::Error>::new()));
+        self.fields.push((key, value));
+        Ok(())
+    }
+
+    fn end(self) -> Result<(), Self::Error> {
+        try!(self.map.serialize_value(&Content::Struct(self.name, self.fields)));
+        Ok(())
+    }
+}

serde/src/ser/impls.rs

@@ -111,7 +111,7 @@ where
 
 ////////////////////////////////////////////////////////////////////////////////
 
-impl<T> Serialize for PhantomData<T> {
+impl<T: ?Sized> Serialize for PhantomData<T> {
     #[inline]
     fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
     where
@@ -351,6 +351,7 @@ deref_impl!(<'a, T: ?Sized> Serialize for Cow<'a, T> where T: Serialize + ToOwne
 ////////////////////////////////////////////////////////////////////////////////
 
 #[cfg(feature = "unstable")]
+#[allow(deprecated)]
 impl<T> Serialize for NonZero<T>
 where
     T: Serialize + Zeroable + Clone,
@@ -363,6 +364,32 @@ where
     }
 }
 
+macro_rules! nonzero_integers {
+    ( $( $T: ident, )+ ) => {
+        $(
+            #[cfg(feature = "unstable")]
+            impl Serialize for $T {
+                fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
+                where
+                    S: Serializer,
+                {
+                    self.get().serialize(serializer)
+                }
+            }
+        )+
+    }
+}
+
+nonzero_integers! {
+    // Not including signed NonZeroI* since they might be removed
+    NonZeroU8,
+    NonZeroU16,
+    NonZeroU32,
+    NonZeroU64,
+    // FIXME: https://github.com/serde-rs/serde/issues/1136 NonZeroU128,
+    NonZeroUsize,
+}
+
 impl<T> Serialize for Cell<T>
 where
     T: Serialize + Copy,

serde/src/ser/mod.rs

@@ -93,7 +93,8 @@
 //!    - Path
 //!    - PathBuf
 //!    - Range\<T\>
-//!    - NonZero\<T\> (unstable)
+//!    - NonZero\<T\> (unstable, deprecated)
+//!    - num::NonZero* (unstable)
 //!  - **Net types**:
 //!    - IpAddr
 //!    - Ipv4Addr

serde_derive/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "serde_derive"
-version = "1.0.25" # remember to update html_root_url
+version = "1.0.35" # 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)]"
@@ -23,9 +23,10 @@ name = "serde_derive"
 proc-macro = true
 
 [dependencies]
-quote = "0.3.8"
-serde_derive_internals = { version = "=0.18.1", default-features = false, path = "../serde_derive_internals" }
-syn = { version = "0.11", features = ["visit"] }
+proc-macro2 = "0.2"
+quote = "0.4"
+serde_derive_internals = { version = "=0.22.1", default-features = false, path = "../serde_derive_internals" }
+syn = { version = "0.12", features = ["visit"] }
 
 [dev-dependencies]
 serde = { version = "1.0", path = "../serde" }

serde_derive/src/bound.rs

@@ -9,27 +9,30 @@
 use std::collections::HashSet;
 
 use syn::{self, visit};
+use syn::punctuated::Punctuated;
 
-use internals::ast::{Body, Container};
+use internals::ast::{Data, Container};
 use internals::attr;
 
-macro_rules! path {
-    ($($path:tt)+) => {
-        syn::parse_path(quote!($($path)+).as_str()).unwrap()
-    };
-}
+use proc_macro2::{Span, Term};
 
 // Remove the default from every type parameter because in the generated impls
 // they look like associated types: "error: associated type bindings are not
 // allowed here".
 pub fn without_defaults(generics: &syn::Generics) -> syn::Generics {
     syn::Generics {
-        ty_params: generics
-            .ty_params
+        params: generics
+            .params
             .iter()
-            .map(|ty_param| syn::TyParam {
-                default: None,
-                ..ty_param.clone()
+            .map(|param| match *param {
+                syn::GenericParam::Type(ref param) => {
+                    syn::GenericParam::Type(syn::TypeParam {
+                        eq_token: None,
+                        default: None,
+                        ..param.clone()
+                    })
+                }
+                _ => param.clone(),
             })
             .collect(),
         ..generics.clone()
@@ -41,10 +44,17 @@ pub fn with_where_predicates(
     predicates: &[syn::WherePredicate],
 ) -> syn::Generics {
     let mut generics = generics.clone();
-    generics
-        .where_clause
+    if generics.where_clause.is_none() {
+        generics.where_clause = Some(syn::WhereClause {
+            where_token: Default::default(),
+            predicates: Punctuated::new(),
+        });
+    }
+    generics.where_clause
+        .as_mut()
+        .unwrap()
         .predicates
-        .extend_from_slice(predicates);
+        .extend(predicates.into_iter().cloned());
     generics
 }
 
@@ -56,13 +66,23 @@ pub fn with_where_predicates_from_fields<F>(
 where
     F: Fn(&attr::Field) -> Option<&[syn::WherePredicate]>,
 {
-    let predicates = cont.body
+    let predicates = cont.data
         .all_fields()
         .flat_map(|field| from_field(&field.attrs))
         .flat_map(|predicates| predicates.to_vec());
 
     let mut generics = generics.clone();
-    generics.where_clause.predicates.extend(predicates);
+    if generics.where_clause.is_none() {
+        generics.where_clause = Some(syn::WhereClause {
+            where_token: Default::default(),
+            predicates: Punctuated::new(),
+        });
+    }
+    generics.where_clause
+        .as_mut()
+        .unwrap()
+        .predicates
+        .extend(predicates);
     generics
 }
 
@@ -95,22 +115,22 @@ where
         // them.
         relevant_ty_params: HashSet<syn::Ident>,
     }
-    impl visit::Visitor for FindTyParams {
+    impl<'ast> visit::Visit<'ast> for FindTyParams {
         fn visit_path(&mut self, path: &syn::Path) {
             if let Some(seg) = path.segments.last() {
-                if seg.ident == "PhantomData" {
+                if seg.into_value().ident == "PhantomData" {
                     // Hardcoded exception, because PhantomData<T> implements
                     // Serialize and Deserialize whether or not T implements it.
                     return;
                 }
             }
-            if !path.global && path.segments.len() == 1 {
-                let id = path.segments[0].ident.clone();
+            if path.leading_colon.is_none() && path.segments.len() == 1 {
+                let id = path.segments[0].ident;
                 if self.all_ty_params.contains(&id) {
                     self.relevant_ty_params.insert(id);
                 }
             }
-            visit::walk_path(self, path);
+            visit::visit_path(self, path);
         }
 
         // Type parameter should not be considered used by a macro path.
@@ -119,61 +139,79 @@ where
         //         mac: T!(),
         //         marker: PhantomData<T>,
         //     }
-        fn visit_mac(&mut self, _mac: &syn::Mac) {}
+        fn visit_macro(&mut self, _mac: &syn::Macro) {}
     }
 
     let all_ty_params: HashSet<_> = generics
-        .ty_params
+        .params
         .iter()
-        .map(|ty_param| ty_param.ident.clone())
+        .filter_map(|param| match *param {
+            syn::GenericParam::Type(ref param) => Some(param.ident),
+            _ => None,
+        })
         .collect();
 
     let mut visitor = FindTyParams {
         all_ty_params: all_ty_params,
         relevant_ty_params: HashSet::new(),
     };
-    match cont.body {
-        Body::Enum(ref variants) => for variant in variants.iter() {
+    match cont.data {
+        Data::Enum(ref variants) => for variant in variants.iter() {
             let relevant_fields = variant
                 .fields
                 .iter()
                 .filter(|field| filter(&field.attrs, Some(&variant.attrs)));
             for field in relevant_fields {
-                visit::walk_ty(&mut visitor, field.ty);
+                visit::visit_type(&mut visitor, field.ty);
             }
         },
-        Body::Struct(_, ref fields) => {
+        Data::Struct(_, ref fields) => {
             for field in fields.iter().filter(|field| filter(&field.attrs, None)) {
-                visit::walk_ty(&mut visitor, field.ty);
+                visit::visit_type(&mut visitor, field.ty);
             }
         }
     }
 
     let new_predicates = generics
-        .ty_params
+        .params
         .iter()
-        .map(|ty_param| ty_param.ident.clone())
+        .filter_map(|param| match *param {
+            syn::GenericParam::Type(ref param) => Some(param.ident),
+            _ => None,
+        })
         .filter(|id| visitor.relevant_ty_params.contains(id))
         .map(|id| {
-            syn::WherePredicate::BoundPredicate(syn::WhereBoundPredicate {
-                bound_lifetimes: Vec::new(),
+            syn::WherePredicate::Type(syn::PredicateType {
+                lifetimes: None,
                 // the type parameter that is being bounded e.g. T
-                bounded_ty: syn::Ty::Path(None, id.into()),
+                bounded_ty: syn::Type::Path(syn::TypePath {
+                    qself: None,
+                    path: id.into(),
+                }),
+                colon_token: Default::default(),
                 // the bound e.g. Serialize
                 bounds: vec![
-                    syn::TyParamBound::Trait(
-                        syn::PolyTraitRef {
-                            bound_lifetimes: Vec::new(),
-                            trait_ref: bound.clone(),
-                        },
-                        syn::TraitBoundModifier::None,
-                    ),
-                ],
+                    syn::TypeParamBound::Trait(syn::TraitBound {
+                        modifier: syn::TraitBoundModifier::None,
+                        lifetimes: None,
+                        path: bound.clone(),
+                    }),
+                ].into_iter().collect(),
             })
         });
 
     let mut generics = generics.clone();
-    generics.where_clause.predicates.extend(new_predicates);
+    if generics.where_clause.is_none() {
+        generics.where_clause = Some(syn::WhereClause {
+            where_token: Default::default(),
+            predicates: Punctuated::new(),
+        });
+    }
+    generics.where_clause
+        .as_mut()
+        .unwrap()
+        .predicates
+        .extend(new_predicates);
     generics
 }
 
@@ -183,76 +221,102 @@ pub fn with_self_bound(
     bound: &syn::Path,
 ) -> syn::Generics {
     let mut generics = generics.clone();
-    generics
-        .where_clause
+    if generics.where_clause.is_none() {
+        generics.where_clause = Some(syn::WhereClause {
+            where_token: Default::default(),
+            predicates: Punctuated::new(),
+        });
+    }
+    generics.where_clause
+        .as_mut()
+        .unwrap()
         .predicates
-        .push(syn::WherePredicate::BoundPredicate(
-            syn::WhereBoundPredicate {
-                bound_lifetimes: Vec::new(),
-                // the type that is being bounded e.g. MyStruct<'a, T>
-                bounded_ty: type_of_item(cont),
-                // the bound e.g. Default
-                bounds: vec![
-                    syn::TyParamBound::Trait(
-                        syn::PolyTraitRef {
-                            bound_lifetimes: Vec::new(),
-                            trait_ref: bound.clone(),
-                        },
-                        syn::TraitBoundModifier::None,
-                    ),
-                ],
-            },
-        ));
+        .push(syn::WherePredicate::Type(syn::PredicateType {
+            lifetimes: None,
+            // the type that is being bounded e.g. MyStruct<'a, T>
+            bounded_ty: type_of_item(cont),
+            colon_token: Default::default(),
+            // the bound e.g. Default
+            bounds: vec![
+                syn::TypeParamBound::Trait(syn::TraitBound {
+                    modifier: syn::TraitBoundModifier::None,
+                    lifetimes: None,
+                    path: bound.clone(),
+                }),
+            ].into_iter().collect(),
+        }));
     generics
 }
 
 pub fn with_lifetime_bound(generics: &syn::Generics, lifetime: &str) -> syn::Generics {
-    let mut generics = generics.clone();
-
-    for lifetime_def in &mut generics.lifetimes {
-        lifetime_def.bounds.push(syn::Lifetime::new(lifetime));
-    }
-
-    for ty_param in &mut generics.ty_params {
-        ty_param
-            .bounds
-            .push(syn::TyParamBound::Region(syn::Lifetime::new(lifetime)));
-    }
-
-    generics.lifetimes.push(syn::LifetimeDef {
+    let bound = syn::Lifetime::new(Term::intern(lifetime), Span::def_site());
+    let def = syn::LifetimeDef {
         attrs: Vec::new(),
-        lifetime: syn::Lifetime::new(lifetime),
-        bounds: Vec::new(),
-    });
+        lifetime: bound,
+        colon_token: None,
+        bounds: Punctuated::new(),
+    };
 
-    generics
+    let params = Some(syn::GenericParam::Lifetime(def))
+        .into_iter()
+        .chain(generics.params
+            .iter()
+            .cloned()
+            .map(|mut param| {
+                match param {
+                    syn::GenericParam::Lifetime(ref mut param) => {
+                        param.bounds.push(bound);
+                    }
+                    syn::GenericParam::Type(ref mut param) => {
+                        param.bounds.push(syn::TypeParamBound::Lifetime(bound));
+                    }
+                    syn::GenericParam::Const(_) => {}
+                }
+                param
+            }))
+        .collect();
+
+    syn::Generics {
+        params: params,
+        ..generics.clone()
+    }
 }
 
-fn type_of_item(cont: &Container) -> syn::Ty {
-    syn::Ty::Path(
-        None,
-        syn::Path {
-            global: false,
+fn type_of_item(cont: &Container) -> syn::Type {
+    syn::Type::Path(syn::TypePath {
+        qself: None,
+        path: syn::Path {
+            leading_colon: None,
             segments: vec![
                 syn::PathSegment {
-                    ident: cont.ident.clone(),
-                    parameters: syn::PathParameters::AngleBracketed(
-                        syn::AngleBracketedParameterData {
-                            lifetimes: cont.generics
-                                .lifetimes
+                    ident: cont.ident,
+                    arguments: syn::PathArguments::AngleBracketed(
+                        syn::AngleBracketedGenericArguments {
+                            colon2_token: None,
+                            lt_token: Default::default(),
+                            args: cont.generics
+                                .params
                                 .iter()
-                                .map(|def| def.lifetime.clone())
+                                .map(|param| match *param {
+                                    syn::GenericParam::Type(ref param) => {
+                                        syn::GenericArgument::Type(syn::Type::Path(syn::TypePath {
+                                            qself: None,
+                                            path: param.ident.into(),
+                                        }))
+                                    }
+                                    syn::GenericParam::Lifetime(ref param) => {
+                                        syn::GenericArgument::Lifetime(param.lifetime)
+                                    }
+                                    syn::GenericParam::Const(_) => {
+                                        panic!("Serde does not support const generics yet");
+                                    }
+                                })
                                 .collect(),
-                            types: cont.generics
-                                .ty_params
-                                .iter()
-                                .map(|param| syn::Ty::Path(None, param.ident.clone().into()))
-                                .collect(),
-                            bindings: Vec::new(),
+                            gt_token: Default::default(),
                         },
                     ),
                 },
-            ],
+            ].into_iter().collect(),
         },
-    )
+    })
 }

serde_derive/src/fragment.rs

@@ -7,6 +7,7 @@
 // except according to those terms.
 
 use quote::{ToTokens, Tokens};
+use syn::token;
 
 pub enum Fragment {
     /// Tokens that can be used as an expression.
@@ -36,9 +37,7 @@ impl ToTokens for Expr {
         match self.0 {
             Fragment::Expr(ref expr) => expr.to_tokens(out),
             Fragment::Block(ref block) => {
-                out.append("{");
-                block.to_tokens(out);
-                out.append("}");
+                token::Brace::default().surround(out, |out| block.to_tokens(out));
             }
         }
     }
@@ -63,12 +62,10 @@ impl ToTokens for Match {
         match self.0 {
             Fragment::Expr(ref expr) => {
                 expr.to_tokens(out);
-                out.append(",");
+                <Token![,]>::default().to_tokens(out);
             }
             Fragment::Block(ref block) => {
-                out.append("{");
-                block.to_tokens(out);
-                out.append("}");
+                token::Brace::default().surround(out, |out| block.to_tokens(out));
             }
         }
     }

serde_derive/src/lib.rs

@@ -22,20 +22,24 @@
 //!
 //! [https://serde.rs/derive.html]: https://serde.rs/derive.html
 
-#![doc(html_root_url = "https://docs.rs/serde_derive/1.0.25")]
-#![cfg_attr(feature = "cargo-clippy", allow(too_many_arguments))]
-#![cfg_attr(feature = "cargo-clippy", allow(used_underscore_binding))]
+#![doc(html_root_url = "https://docs.rs/serde_derive/1.0.35")]
+#![cfg_attr(feature = "cargo-clippy", allow(enum_variant_names, redundant_field_names,
+                                            too_many_arguments, used_underscore_binding))]
 // The `quote!` macro requires deep recursion.
-#![recursion_limit = "192"]
+#![recursion_limit = "512"]
 
 #[macro_use]
 extern crate quote;
+#[macro_use]
 extern crate syn;
 
 extern crate serde_derive_internals as internals;
 
 extern crate proc_macro;
+extern crate proc_macro2;
+
 use proc_macro::TokenStream;
+use syn::DeriveInput;
 
 #[macro_use]
 mod bound;
@@ -47,18 +51,18 @@ mod de;
 
 #[proc_macro_derive(Serialize, attributes(serde))]
 pub fn derive_serialize(input: TokenStream) -> TokenStream {
-    let input = syn::parse_derive_input(&input.to_string()).unwrap();
+    let input: DeriveInput = syn::parse(input).unwrap();
     match ser::expand_derive_serialize(&input) {
-        Ok(expanded) => expanded.parse().unwrap(),
+        Ok(expanded) => expanded.into(),
         Err(msg) => panic!(msg),
     }
 }
 
 #[proc_macro_derive(Deserialize, attributes(serde))]
 pub fn derive_deserialize(input: TokenStream) -> TokenStream {
-    let input = syn::parse_derive_input(&input.to_string()).unwrap();
+    let input: DeriveInput = syn::parse(input).unwrap();
     match de::expand_derive_deserialize(&input) {
-        Ok(expanded) => expanded.parse().unwrap(),
+        Ok(expanded) => expanded.into(),
         Err(msg) => panic!(msg),
     }
 }

serde_derive/src/ser.rs

@@ -6,12 +6,14 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-use syn::{self, Ident};
+use syn::{self, Ident, Index, Member};
+use syn::spanned::Spanned;
 use quote::Tokens;
+use proc_macro2::Span;
 
 use bound;
 use fragment::{Fragment, Match, Stmts};
-use internals::ast::{Body, Container, Field, Style, Variant};
+use internals::ast::{Data, Container, Field, Style, Variant};
 use internals::{attr, Ctxt};
 
 use std::u32;
@@ -25,14 +27,15 @@ pub fn expand_derive_serialize(input: &syn::DeriveInput) -> Result<Tokens, Strin
     let ident = &cont.ident;
     let params = Parameters::new(&cont);
     let (impl_generics, ty_generics, where_clause) = params.generics.split_for_impl();
-    let dummy_const = Ident::new(format!("_IMPL_SERIALIZE_FOR_{}", ident));
+    let dummy_const = Ident::new(&format!("_IMPL_SERIALIZE_FOR_{}", ident), Span::def_site());
     let body = Stmts(serialize_body(&cont, &params));
 
     let impl_block = if let Some(remote) = cont.attrs.remote() {
         let vis = &input.vis;
+        let fun = quote_spanned!(Span::call_site()=> serialize);
         quote! {
             impl #impl_generics #ident #ty_generics #where_clause {
-                #vis fn serialize<__S>(__self: &#remote #ty_generics, __serializer: __S) -> _serde::export::Result<__S::Ok, __S::Error>
+                #vis fn #fun<__S>(__self: &#remote #ty_generics, __serializer: __S) -> _serde::export::Result<__S::Ok, __S::Error>
                     where __S: _serde::Serializer
                 {
                     #body
@@ -95,14 +98,14 @@ impl Parameters {
     fn new(cont: &Container) -> Self {
         let is_remote = cont.attrs.remote().is_some();
         let self_var = if is_remote {
-            Ident::new("__self")
+            Ident::new("__self", Span::def_site())
         } else {
-            Ident::new("self")
+            Ident::new("self", Span::def_site())
         };
 
         let this = match cont.attrs.remote() {
             Some(remote) => remote.clone(),
-            None => cont.ident.clone().into(),
+            None => cont.ident.into(),
         };
 
         let generics = build_generics(cont);
@@ -118,7 +121,7 @@ impl Parameters {
     /// Type name to use in error messages and `&'static str` arguments to
     /// various Serializer methods.
     fn type_name(&self) -> &str {
-        self.this.segments.last().unwrap().ident.as_ref()
+        self.this.segments.last().unwrap().value().ident.as_ref()
     }
 }
 
@@ -136,7 +139,7 @@ fn build_generics(cont: &Container) -> syn::Generics {
             cont,
             &generics,
             needs_serialize_bound,
-            &path!(_serde::Serialize),
+            &parse_quote!(_serde::Serialize),
         ),
     }
 }
@@ -152,36 +155,36 @@ fn needs_serialize_bound(field: &attr::Field, variant: Option<&attr::Variant>) -
 }
 
 fn serialize_body(cont: &Container, params: &Parameters) -> Fragment {
-    if let Some(into_type) = cont.attrs.into_type() {
-        serialize_into(params, into_type)
+    if let Some(type_into) = cont.attrs.type_into() {
+        serialize_into(params, type_into)
     } else {
-        match cont.body {
-            Body::Enum(ref variants) => serialize_enum(params, variants, &cont.attrs),
-            Body::Struct(Style::Struct, ref fields) => {
+        match cont.data {
+            Data::Enum(ref variants) => serialize_enum(params, variants, &cont.attrs),
+            Data::Struct(Style::Struct, ref fields) => {
                 if fields.iter().any(|field| field.ident.is_none()) {
                     panic!("struct has unnamed fields");
                 }
                 serialize_struct(params, fields, &cont.attrs)
             }
-            Body::Struct(Style::Tuple, ref fields) => {
+            Data::Struct(Style::Tuple, ref fields) => {
                 if fields.iter().any(|field| field.ident.is_some()) {
                     panic!("tuple struct has named fields");
                 }
                 serialize_tuple_struct(params, fields, &cont.attrs)
             }
-            Body::Struct(Style::Newtype, ref fields) => {
+            Data::Struct(Style::Newtype, ref fields) => {
                 serialize_newtype_struct(params, &fields[0], &cont.attrs)
             }
-            Body::Struct(Style::Unit, _) => serialize_unit_struct(&cont.attrs),
+            Data::Struct(Style::Unit, _) => serialize_unit_struct(&cont.attrs),
         }
     }
 }
 
-fn serialize_into(params: &Parameters, into_type: &syn::Ty) -> Fragment {
+fn serialize_into(params: &Parameters, type_into: &syn::Type) -> Fragment {
     let self_var = &params.self_var;
     quote_block! {
         _serde::Serialize::serialize(
-            &_serde::export::Into::<#into_type>::into(_serde::export::Clone::clone(#self_var)),
+            &_serde::export::Into::<#type_into>::into(_serde::export::Clone::clone(#self_var)),
             __serializer)
     }
 }
@@ -201,13 +204,18 @@ fn serialize_newtype_struct(
 ) -> Fragment {
     let type_name = cattrs.name().serialize_name();
 
-    let mut field_expr = get_field(params, field, 0);
+    let mut field_expr = get_member(params, field, &Member::Unnamed(Index {
+        index: 0,
+        span: Span::call_site(),
+    }));
     if let Some(path) = field.attrs.serialize_with() {
-        field_expr = wrap_serialize_field_with(params, field.ty, path, field_expr);
+        field_expr = wrap_serialize_field_with(params, field.ty, path, &field_expr);
     }
 
+    let span = Span::def_site().located_at(field.original.span());
+    let func = quote_spanned!(span=> _serde::Serializer::serialize_newtype_struct);
     quote_expr! {
-        _serde::Serializer::serialize_newtype_struct(__serializer, #type_name, #field_expr)
+        #func(__serializer, #type_name, #field_expr)
     }
 }
 
@@ -220,7 +228,7 @@ fn serialize_tuple_struct(
         fields,
         params,
         false,
-        quote!(_serde::ser::SerializeTupleStruct::serialize_field),
+        &TupleTrait::SerializeTupleStruct,
     );
 
     let type_name = cattrs.name().serialize_name();
@@ -235,14 +243,21 @@ fn serialize_tuple_struct(
 }
 
 fn serialize_struct(params: &Parameters, fields: &[Field], cattrs: &attr::Container) -> Fragment {
-    assert!(fields.len() as u64 <= u32::MAX as u64);
+    assert!(fields.len() as u64 <= u64::from(u32::MAX));
 
+    if cattrs.has_flatten() {
+        serialize_struct_as_map(params, fields, cattrs)
+    } else {
+        serialize_struct_as_struct(params, fields, cattrs)
+    }
+}
+
+fn serialize_struct_as_struct(params: &Parameters, fields: &[Field], cattrs: &attr::Container) -> Fragment {
     let serialize_fields = serialize_struct_visitor(
         fields,
         params,
         false,
-        quote!(_serde::ser::SerializeStruct::serialize_field),
-        quote!(_serde::ser::SerializeStruct::skip_field),
+        &StructTrait::SerializeStruct,
     );
 
     let type_name = cattrs.name().serialize_name();
@@ -258,8 +273,8 @@ fn serialize_struct(params: &Parameters, fields: &[Field], cattrs: &attr::Contai
         .map(|field| match field.attrs.skip_serializing_if() {
             None => quote!(1),
             Some(path) => {
-                let ident = field.ident.clone().expect("struct has unnamed fields");
-                let field_expr = get_field(params, field, ident);
+                let ident = field.ident.expect("struct has unnamed fields");
+                let field_expr = get_member(params, field, &Member::Named(ident));
                 quote!(if #path(#field_expr) { 0 } else { 1 })
             }
         })
@@ -272,8 +287,46 @@ fn serialize_struct(params: &Parameters, fields: &[Field], cattrs: &attr::Contai
     }
 }
 
+fn serialize_struct_as_map(params: &Parameters, fields: &[Field], cattrs: &attr::Container) -> Fragment {
+    let serialize_fields = serialize_struct_visitor(
+        fields,
+        params,
+        false,
+        &StructTrait::SerializeMap,
+    );
+
+    let mut serialized_fields = fields
+        .iter()
+        .filter(|&field| !field.attrs.skip_serializing())
+        .peekable();
+
+    let let_mut = mut_if(serialized_fields.peek().is_some());
+
+    let len = if cattrs.has_flatten() {
+        quote!(_serde::export::None)
+    } else {
+        let len = serialized_fields
+            .map(|field| match field.attrs.skip_serializing_if() {
+                None => quote!(1),
+                Some(path) => {
+                    let ident = field.ident.expect("struct has unnamed fields");
+                    let field_expr = get_member(params, field, &Member::Named(ident));
+                    quote!(if #path(#field_expr) { 0 } else { 1 })
+                }
+            })
+            .fold(quote!(0), |sum, expr| quote!(#sum + #expr));
+        quote!(_serde::export::Some(#len))
+    };
+
+    quote_block! {
+        let #let_mut __serde_state = try!(_serde::Serializer::serialize_map(__serializer, #len));
+        #(#serialize_fields)*
+        _serde::ser::SerializeMap::end(__serde_state)
+    }
+}
+
 fn serialize_enum(params: &Parameters, variants: &[Variant], cattrs: &attr::Container) -> Fragment {
-    assert!(variants.len() as u64 <= u32::MAX as u64);
+    assert!(variants.len() as u64 <= u64::from(u32::MAX));
 
     let self_var = &params.self_var;
 
@@ -299,7 +352,7 @@ fn serialize_variant(
     cattrs: &attr::Container,
 ) -> Tokens {
     let this = &params.this;
-    let variant_ident = variant.ident.clone();
+    let variant_ident = variant.ident;
 
     if variant.attrs.skip_serializing() {
         let skipped_msg = format!(
@@ -333,7 +386,7 @@ fn serialize_variant(
             }
             Style::Tuple => {
                 let field_names =
-                    (0..variant.fields.len()).map(|i| Ident::new(format!("__field{}", i)));
+                    (0..variant.fields.len()).map(|i| Ident::new(&format!("__field{}", i), Span::def_site()));
                 quote! {
                     #this::#variant_ident(#(ref #field_names),*)
                 }
@@ -342,7 +395,7 @@ fn serialize_variant(
                 let fields = variant
                     .fields
                     .iter()
-                    .map(|f| f.ident.clone().expect("struct variant has unnamed fields"));
+                    .map(|f| f.ident.expect("struct variant has unnamed fields"));
                 quote! {
                     #this::#variant_ident { #(ref #fields),* }
                 }
@@ -379,7 +432,7 @@ fn serialize_externally_tagged_variant(
     let variant_name = variant.attrs.name().serialize_name();
 
     if let Some(path) = variant.attrs.serialize_with() {
-        let ser = wrap_serialize_variant_with(params, path, &variant);
+        let ser = wrap_serialize_variant_with(params, path, variant);
         return quote_expr! {
             _serde::Serializer::serialize_newtype_variant(
                 __serializer,
@@ -406,7 +459,7 @@ fn serialize_externally_tagged_variant(
             let field = &variant.fields[0];
             let mut field_expr = quote!(__field0);
             if let Some(path) = field.attrs.serialize_with() {
-                field_expr = wrap_serialize_field_with(params, field.ty, path, field_expr);
+                field_expr = wrap_serialize_field_with(params, field.ty, path, &field_expr);
             }
 
             quote_expr! {
@@ -453,7 +506,7 @@ fn serialize_internally_tagged_variant(
     let variant_ident_str = variant.ident.as_ref();
 
     if let Some(path) = variant.attrs.serialize_with() {
-        let ser = wrap_serialize_variant_with(params, path, &variant);
+        let ser = wrap_serialize_variant_with(params, path, variant);
         return quote_expr! {
             _serde::private::ser::serialize_tagged_newtype(
                 __serializer,
@@ -480,7 +533,7 @@ fn serialize_internally_tagged_variant(
             let field = &variant.fields[0];
             let mut field_expr = quote!(__field0);
             if let Some(path) = field.attrs.serialize_with() {
-                field_expr = wrap_serialize_field_with(params, field.ty, path, field_expr);
+                field_expr = wrap_serialize_field_with(params, field.ty, path, &field_expr);
             }
 
             quote_expr! {
@@ -519,7 +572,7 @@ fn serialize_adjacently_tagged_variant(
     let variant_name = variant.attrs.name().serialize_name();
 
     let inner = Stmts(if let Some(path) = variant.attrs.serialize_with() {
-        let ser = wrap_serialize_variant_with(params, path, &variant);
+        let ser = wrap_serialize_variant_with(params, path, variant);
         quote_expr! {
             _serde::Serialize::serialize(#ser, __serializer)
         }
@@ -538,7 +591,7 @@ fn serialize_adjacently_tagged_variant(
                 let field = &variant.fields[0];
                 let mut field_expr = quote!(__field0);
                 if let Some(path) = field.attrs.serialize_with() {
-                    field_expr = wrap_serialize_field_with(params, field.ty, path, field_expr);
+                    field_expr = wrap_serialize_field_with(params, field.ty, path, &field_expr);
                 }
 
                 quote_expr! {
@@ -558,7 +611,7 @@ fn serialize_adjacently_tagged_variant(
     });
 
     let fields_ty = variant.fields.iter().map(|f| &f.ty);
-    let ref fields_ident: Vec<_> = match variant.style {
+    let fields_ident: &Vec<_> = &match variant.style {
         Style::Unit => {
             if variant.attrs.serialize_with().is_some() {
                 vec![]
@@ -566,14 +619,14 @@ fn serialize_adjacently_tagged_variant(
                 unreachable!()
             }
         }
-        Style::Newtype => vec![Ident::new("__field0")],
+        Style::Newtype => vec![Ident::new("__field0", Span::def_site())],
         Style::Tuple => (0..variant.fields.len())
-            .map(|i| Ident::new(format!("__field{}", i)))
+            .map(|i| Ident::new(&format!("__field{}", i), Span::def_site()))
             .collect(),
         Style::Struct => variant
             .fields
             .iter()
-            .map(|f| f.ident.clone().expect("struct variant has unnamed fields"))
+            .map(|f| f.ident.expect("struct variant has unnamed fields"))
             .collect(),
     };
 
@@ -620,7 +673,7 @@ fn serialize_untagged_variant(
     cattrs: &attr::Container,
 ) -> Fragment {
     if let Some(path) = variant.attrs.serialize_with() {
-        let ser = wrap_serialize_variant_with(params, path, &variant);
+        let ser = wrap_serialize_variant_with(params, path, variant);
         return quote_expr! {
             _serde::Serialize::serialize(#ser, __serializer)
         };
@@ -636,7 +689,7 @@ fn serialize_untagged_variant(
             let field = &variant.fields[0];
             let mut field_expr = quote!(__field0);
             if let Some(path) = field.attrs.serialize_with() {
-                field_expr = wrap_serialize_field_with(params, field.ty, path, field_expr);
+                field_expr = wrap_serialize_field_with(params, field.ty, path, &field_expr);
             }
 
             quote_expr! {
@@ -665,14 +718,12 @@ fn serialize_tuple_variant(
     params: &Parameters,
     fields: &[Field],
 ) -> Fragment {
-    let method = match context {
-        TupleVariant::ExternallyTagged { .. } => {
-            quote!(_serde::ser::SerializeTupleVariant::serialize_field)
-        }
-        TupleVariant::Untagged => quote!(_serde::ser::SerializeTuple::serialize_element),
+    let tuple_trait = match context {
+        TupleVariant::ExternallyTagged { .. } => TupleTrait::SerializeTupleVariant,
+        TupleVariant::Untagged => TupleTrait::SerializeTuple,
     };
 
-    let serialize_stmts = serialize_tuple_struct_visitor(fields, params, true, method);
+    let serialize_stmts = serialize_tuple_struct_visitor(fields, params, true, &tuple_trait);
 
     let len = serialize_stmts.len();
     let let_mut = mut_if(len > 0);
@@ -724,18 +775,16 @@ fn serialize_struct_variant<'a>(
     fields: &[Field],
     name: &str,
 ) -> Fragment {
-    let (method, skip_method) = match context {
+    let struct_trait = match context {
         StructVariant::ExternallyTagged { .. } => (
-            quote!(_serde::ser::SerializeStructVariant::serialize_field),
-            quote!(_serde::ser::SerializeStructVariant::skip_field),
+            StructTrait::SerializeStructVariant
         ),
         StructVariant::InternallyTagged { .. } | StructVariant::Untagged => (
-            quote!(_serde::ser::SerializeStruct::serialize_field),
-            quote!(_serde::ser::SerializeStruct::skip_field),
+            StructTrait::SerializeStruct
         ),
     };
 
-    let serialize_fields = serialize_struct_visitor(fields, params, true, method, skip_method);
+    let serialize_fields = serialize_struct_visitor(fields, params, true, &struct_trait);
 
     let mut serialized_fields = fields
         .iter()
@@ -746,7 +795,7 @@ fn serialize_struct_variant<'a>(
 
     let len = serialized_fields
         .map(|field| {
-            let ident = field.ident.clone().expect("struct has unnamed fields");
+            let ident = field.ident.expect("struct has unnamed fields");
 
             match field.attrs.skip_serializing_if() {
                 Some(path) => quote!(if #path(#ident) { 0 } else { 1 }),
@@ -806,17 +855,20 @@ fn serialize_tuple_struct_visitor(
     fields: &[Field],
     params: &Parameters,
     is_enum: bool,
-    func: Tokens,
+    tuple_trait: &TupleTrait,
 ) -> Vec<Tokens> {
     fields
         .iter()
         .enumerate()
         .map(|(i, field)| {
             let mut field_expr = if is_enum {
-                let id = Ident::new(format!("__field{}", i));
+                let id = Ident::new(&format!("__field{}", i), Span::def_site());
                 quote!(#id)
             } else {
-                get_field(params, field, i)
+                get_member(params, field, &Member::Unnamed(Index {
+                    index: i as u32,
+                    span: Span::call_site(),
+                }))
             };
 
             let skip = field
@@ -825,9 +877,11 @@ fn serialize_tuple_struct_visitor(
                 .map(|path| quote!(#path(#field_expr)));
 
             if let Some(path) = field.attrs.serialize_with() {
-                field_expr = wrap_serialize_field_with(params, field.ty, path, field_expr);
+                field_expr = wrap_serialize_field_with(params, field.ty, path, &field_expr);
             }
 
+            let span = Span::def_site().located_at(field.original.span());
+            let func = tuple_trait.serialize_element(span);
             let ser = quote! {
                 try!(#func(&mut __serde_state, #field_expr));
             };
@@ -844,18 +898,18 @@ fn serialize_struct_visitor(
     fields: &[Field],
     params: &Parameters,
     is_enum: bool,
-    func: Tokens,
-    skip_func: Tokens,
+    struct_trait: &StructTrait,
 ) -> Vec<Tokens> {
     fields
         .iter()
         .filter(|&field| !field.attrs.skip_serializing())
         .map(|field| {
-            let field_ident = field.ident.clone().expect("struct has unnamed field");
+            let field_ident = field.ident.expect("struct has unnamed field");
+
             let mut field_expr = if is_enum {
                 quote!(#field_ident)
             } else {
-                get_field(params, field, field_ident)
+                get_member(params, field, &Member::Named(field_ident))
             };
 
             let key_expr = field.attrs.name().serialize_name();
@@ -866,21 +920,37 @@ fn serialize_struct_visitor(
                 .map(|path| quote!(#path(#field_expr)));
 
             if let Some(path) = field.attrs.serialize_with() {
-                field_expr = wrap_serialize_field_with(params, field.ty, path, field_expr);
+                field_expr = wrap_serialize_field_with(params, field.ty, path, &field_expr);
             }
 
-            let ser = quote! {
-                try!(#func(&mut __serde_state, #key_expr, #field_expr));
+            let span = Span::def_site().located_at(field.original.span());
+            let ser = if field.attrs.flatten() {
+                quote! {
+                    try!(_serde::Serialize::serialize(&#field_expr, _serde::private::ser::FlatMapSerializer(&mut __serde_state)));
+                }
+            } else {
+                let func = struct_trait.serialize_field(span);
+                quote! {
+                    try!(#func(&mut __serde_state, #key_expr, #field_expr));
+                }
             };
 
             match skip {
                 None => ser,
                 Some(skip) => {
-                    quote! {
-                        if !#skip {
-                            #ser
-                        } else {
-                            try!(#skip_func(&mut __serde_state, #key_expr));
+                    if let Some(skip_func) = struct_trait.skip_field(span) {
+                        quote! {
+                            if !#skip {
+                                #ser
+                            } else {
+                                try!(#skip_func(&mut __serde_state, #key_expr));
+                            }
+                        }
+                    } else {
+                        quote! {
+                            if !#skip {
+                                #ser
+                            }
                         }
                     }
                 }
@@ -891,16 +961,16 @@ fn serialize_struct_visitor(
 
 fn wrap_serialize_field_with(
     params: &Parameters,
-    field_ty: &syn::Ty,
-    serialize_with: &syn::Path,
-    field_expr: Tokens,
+    field_ty: &syn::Type,
+    serialize_with: &syn::ExprPath,
+    field_expr: &Tokens,
 ) -> Tokens {
     wrap_serialize_with(params, serialize_with, &[field_ty], &[quote!(#field_expr)])
 }
 
 fn wrap_serialize_variant_with(
     params: &Parameters,
-    serialize_with: &syn::Path,
+    serialize_with: &syn::ExprPath,
     variant: &Variant,
 ) -> Tokens {
     let field_tys: Vec<_> = variant.fields.iter().map(|field| field.ty).collect();
@@ -911,8 +981,7 @@ fn wrap_serialize_variant_with(
         .map(|(i, field)| {
             let id = field
                 .ident
-                .as_ref()
-                .map_or_else(|| Ident::new(format!("__field{}", i)), |id| id.clone());
+                .unwrap_or_else(|| Ident::new(&format!("__field{}", i), Span::def_site()));
             quote!(#id)
         })
         .collect();
@@ -926,21 +995,24 @@ fn wrap_serialize_variant_with(
 
 fn wrap_serialize_with(
     params: &Parameters,
-    serialize_with: &syn::Path,
-    field_tys: &[&syn::Ty],
+    serialize_with: &syn::ExprPath,
+    field_tys: &[&syn::Type],
     field_exprs: &[Tokens],
 ) -> Tokens {
     let this = &params.this;
     let (_, ty_generics, where_clause) = params.generics.split_for_impl();
 
-    let wrapper_generics = if field_exprs.len() == 0 {
+    let wrapper_generics = if field_exprs.is_empty() {
         params.generics.clone()
     } else {
         bound::with_lifetime_bound(&params.generics, "'__a")
     };
     let (wrapper_impl_generics, wrapper_ty_generics, _) = wrapper_generics.split_for_impl();
 
-    let field_access = (0..field_exprs.len()).map(|n| Ident::new(format!("{}", n)));
+    let field_access = (0..field_exprs.len()).map(|n| Member::Unnamed(Index {
+        index: n as u32,
+        span: Span::call_site(),
+    }));
 
     quote!({
         struct __SerializeWith #wrapper_impl_generics #where_clause {
@@ -977,20 +1049,16 @@ fn mut_if(is_mut: bool) -> Option<Tokens> {
     }
 }
 
-fn get_field<I>(params: &Parameters, field: &Field, ident: I) -> Tokens
-where
-    I: Into<Ident>,
-{
+fn get_member(params: &Parameters, field: &Field, member: &Member) -> Tokens {
     let self_var = &params.self_var;
     match (params.is_remote, field.attrs.getter()) {
         (false, None) => {
-            let ident = ident.into();
-            quote!(&#self_var.#ident)
+            quote_spanned!(Span::call_site()=> &#self_var.#member)
         }
         (true, None) => {
+            let inner = quote_spanned!(Span::call_site()=> &#self_var.#member);
             let ty = field.ty;
-            let ident = ident.into();
-            quote!(_serde::private::ser::constrain::<#ty>(&#self_var.#ident))
+            quote!(_serde::private::ser::constrain::<#ty>(#inner))
         }
         (true, Some(getter)) => {
             let ty = field.ty;
@@ -1001,3 +1069,59 @@ where
         }
     }
 }
+
+enum StructTrait {
+    SerializeMap,
+    SerializeStruct,
+    SerializeStructVariant,
+}
+
+impl StructTrait {
+    fn serialize_field(&self, span: Span) -> Tokens {
+        match *self {
+            StructTrait::SerializeMap => {
+                quote_spanned!(span=> _serde::ser::SerializeMap::serialize_entry)
+            }
+            StructTrait::SerializeStruct => {
+                quote_spanned!(span=> _serde::ser::SerializeStruct::serialize_field)
+            }
+            StructTrait::SerializeStructVariant => {
+                quote_spanned!(span=> _serde::ser::SerializeStructVariant::serialize_field)
+            }
+        }
+    }
+
+    fn skip_field(&self, span: Span) -> Option<Tokens> {
+        match *self {
+            StructTrait::SerializeMap => None,
+            StructTrait::SerializeStruct => Some({
+                quote_spanned!(span=> _serde::ser::SerializeStruct::skip_field)
+            }),
+            StructTrait::SerializeStructVariant => Some({
+                quote_spanned!(span=> _serde::ser::SerializeStructVariant::skip_field)
+            })
+        }
+    }
+}
+
+enum TupleTrait {
+    SerializeTuple,
+    SerializeTupleStruct,
+    SerializeTupleVariant,
+}
+
+impl TupleTrait {
+    fn serialize_element(&self, span: Span) -> Tokens {
+        match *self {
+            TupleTrait::SerializeTuple => {
+                quote_spanned!(span=> _serde::ser::SerializeTuple::serialize_element)
+            }
+            TupleTrait::SerializeTupleStruct => {
+                quote_spanned!(span=> _serde::ser::SerializeTupleStruct::serialize_field)
+            }
+            TupleTrait::SerializeTupleVariant => {
+                quote_spanned!(span=> _serde::ser::SerializeTupleVariant::serialize_field)
+            }
+        }
+    }
+}

serde_derive_internals/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "serde_derive_internals"
-version = "0.18.1" # remember to update html_root_url
+version = "0.22.1" # remember to update html_root_url
 authors = ["Erick Tryzelaar <erick.tryzelaar@gmail.com>", "David Tolnay <dtolnay@gmail.com>"]
 license = "MIT/Apache-2.0"
 description = "AST representation used by Serde derive macros. Unstable."
@@ -12,8 +12,8 @@ readme = "README.md"
 include = ["Cargo.toml", "src/**/*.rs", "README.md", "LICENSE-APACHE", "LICENSE-MIT"]
 
 [dependencies]
-syn = { version = "0.11.10", default-features = false, features = ["parsing"] }
-synom = "0.11"
+proc-macro2 = "0.2"
+syn = { version = "0.12", default-features = false, features = ["derive", "parsing", "clone-impls"] }
 
 [badges]
 travis-ci = { repository = "serde-rs/serde" }

serde_derive_internals/src/ast.rs

@@ -10,15 +10,16 @@ use syn;
 use attr;
 use check;
 use Ctxt;
+use syn::punctuated::Punctuated;
 
 pub struct Container<'a> {
     pub ident: syn::Ident,
     pub attrs: attr::Container,
-    pub body: Body<'a>,
+    pub data: Data<'a>,
     pub generics: &'a syn::Generics,
 }
 
-pub enum Body<'a> {
+pub enum Data<'a> {
     Enum(Vec<Variant<'a>>),
     Struct(Style, Vec<Field<'a>>),
 }
@@ -33,7 +34,8 @@ pub struct Variant<'a> {
 pub struct Field<'a> {
     pub ident: Option<syn::Ident>,
     pub attrs: attr::Field,
-    pub ty: &'a syn::Ty,
+    pub ty: &'a syn::Type,
+    pub original: &'a syn::Field,
 }
 
 #[derive(Copy, Clone)]
@@ -46,34 +48,45 @@ pub enum Style {
 
 impl<'a> Container<'a> {
     pub fn from_ast(cx: &Ctxt, item: &'a syn::DeriveInput) -> Container<'a> {
-        let attrs = attr::Container::from_ast(cx, item);
+        let mut attrs = attr::Container::from_ast(cx, item);
 
-        let mut body = match item.body {
-            syn::Body::Enum(ref variants) => {
-                Body::Enum(enum_from_ast(cx, variants, &attrs.default()))
+        let mut data = match item.data {
+            syn::Data::Enum(ref data) => {
+                Data::Enum(enum_from_ast(cx, &data.variants, attrs.default()))
             }
-            syn::Body::Struct(ref variant_data) => {
-                let (style, fields) = struct_from_ast(cx, variant_data, None, &attrs.default());
-                Body::Struct(style, fields)
+            syn::Data::Struct(ref data) => {
+                let (style, fields) = struct_from_ast(cx, &data.fields, None, attrs.default());
+                Data::Struct(style, fields)
+            }
+            syn::Data::Union(_) => {
+                panic!("Serde does not support derive for unions");
             }
         };
 
-        match body {
-            Body::Enum(ref mut variants) => for ref mut variant in variants {
+        let mut has_flatten = false;
+        match data {
+            Data::Enum(ref mut variants) => for variant in variants {
                 variant.attrs.rename_by_rule(attrs.rename_all());
-                for ref mut field in &mut variant.fields {
+                for field in &mut variant.fields {
                     field.attrs.rename_by_rule(variant.attrs.rename_all());
                 }
             },
-            Body::Struct(_, ref mut fields) => for field in fields {
+            Data::Struct(_, ref mut fields) => for field in fields {
+                if field.attrs.flatten() {
+                    has_flatten = true;
+                }
                 field.attrs.rename_by_rule(attrs.rename_all());
             },
         }
 
+        if has_flatten {
+            attrs.mark_has_flatten();
+        }
+
         let item = Container {
-            ident: item.ident.clone(),
+            ident: item.ident,
             attrs: attrs,
-            body: body,
+            data: data,
             generics: &item.generics,
         };
         check::check(cx, &item);
@@ -81,13 +94,13 @@ impl<'a> Container<'a> {
     }
 }
 
-impl<'a> Body<'a> {
+impl<'a> Data<'a> {
     pub fn all_fields(&'a self) -> Box<Iterator<Item = &'a Field<'a>> + 'a> {
         match *self {
-            Body::Enum(ref variants) => {
+            Data::Enum(ref variants) => {
                 Box::new(variants.iter().flat_map(|variant| variant.fields.iter()))
             }
-            Body::Struct(_, ref fields) => Box::new(fields.iter()),
+            Data::Struct(_, ref fields) => Box::new(fields.iter()),
         }
     }
 
@@ -98,7 +111,7 @@ impl<'a> Body<'a> {
 
 fn enum_from_ast<'a>(
     cx: &Ctxt,
-    variants: &'a [syn::Variant],
+    variants: &'a Punctuated<syn::Variant, Token![,]>,
     container_default: &attr::Default,
 ) -> Vec<Variant<'a>> {
     variants
@@ -106,9 +119,9 @@ fn enum_from_ast<'a>(
         .map(|variant| {
             let attrs = attr::Variant::from_ast(cx, variant);
             let (style, fields) =
-                struct_from_ast(cx, &variant.data, Some(&attrs), container_default);
+                struct_from_ast(cx, &variant.fields, Some(&attrs), container_default);
             Variant {
-                ident: variant.ident.clone(),
+                ident: variant.ident,
                 attrs: attrs,
                 style: style,
                 fields: fields,
@@ -119,30 +132,30 @@ fn enum_from_ast<'a>(
 
 fn struct_from_ast<'a>(
     cx: &Ctxt,
-    data: &'a syn::VariantData,
+    fields: &'a syn::Fields,
     attrs: Option<&attr::Variant>,
     container_default: &attr::Default,
 ) -> (Style, Vec<Field<'a>>) {
-    match *data {
-        syn::VariantData::Struct(ref fields) => (
+    match *fields {
+        syn::Fields::Named(ref fields) => (
             Style::Struct,
-            fields_from_ast(cx, fields, attrs, container_default),
+            fields_from_ast(cx, &fields.named, attrs, container_default),
         ),
-        syn::VariantData::Tuple(ref fields) if fields.len() == 1 => (
+        syn::Fields::Unnamed(ref fields) if fields.unnamed.len() == 1 => (
             Style::Newtype,
-            fields_from_ast(cx, fields, attrs, container_default),
+            fields_from_ast(cx, &fields.unnamed, attrs, container_default),
         ),
-        syn::VariantData::Tuple(ref fields) => (
+        syn::Fields::Unnamed(ref fields) => (
             Style::Tuple,
-            fields_from_ast(cx, fields, attrs, container_default),
+            fields_from_ast(cx, &fields.unnamed, attrs, container_default),
         ),
-        syn::VariantData::Unit => (Style::Unit, Vec::new()),
+        syn::Fields::Unit => (Style::Unit, Vec::new()),
     }
 }
 
 fn fields_from_ast<'a>(
     cx: &Ctxt,
-    fields: &'a [syn::Field],
+    fields: &'a Punctuated<syn::Field, Token![,]>,
     attrs: Option<&attr::Variant>,
     container_default: &attr::Default,
 ) -> Vec<Field<'a>> {
@@ -150,9 +163,10 @@ fn fields_from_ast<'a>(
         .iter()
         .enumerate()
         .map(|(i, field)| Field {
-            ident: field.ident.clone(),
+            ident: field.ident,
             attrs: attr::Field::from_ast(cx, i, field, attrs, container_default),
             ty: &field.ty,
+            original: field,
         })
         .collect()
 }

serde_derive_internals/src/case.rs

@@ -7,19 +7,21 @@
 // except according to those terms.
 
 // See https://users.rust-lang.org/t/psa-dealing-with-warning-unused-import-std-ascii-asciiext-in-today-s-nightly/13726
-#[allow(unused_imports)]
+#[allow(deprecated, unused_imports)]
 use std::ascii::AsciiExt;
 
 use std::str::FromStr;
 
 use self::RenameRule::*;
 
-#[derive(Debug, PartialEq)]
+#[derive(PartialEq)]
 pub enum RenameRule {
     /// Don't apply a default rename rule.
     None,
     /// Rename direct children to "lowercase" style.
     LowerCase,
+    /// Rename direct children to "UPPERCASE" style.
+    UPPERCASE,
     /// Rename direct children to "PascalCase" style, as typically used for enum variants.
     PascalCase,
     /// Rename direct children to "camelCase" style.
@@ -39,6 +41,7 @@ impl RenameRule {
         match *self {
             None | PascalCase => variant.to_owned(),
             LowerCase => variant.to_ascii_lowercase(),
+            UPPERCASE => variant.to_ascii_uppercase(),
             CamelCase => variant[..1].to_ascii_lowercase() + &variant[1..],
             SnakeCase => {
                 let mut snake = String::new();
@@ -61,6 +64,7 @@ impl RenameRule {
     pub fn apply_to_field(&self, field: &str) -> String {
         match *self {
             None | LowerCase | SnakeCase => field.to_owned(),
+            UPPERCASE => field.to_ascii_uppercase(),
             PascalCase => {
                 let mut pascal = String::new();
                 let mut capitalize = true;
@@ -93,6 +97,7 @@ impl FromStr for RenameRule {
     fn from_str(rename_all_str: &str) -> Result<Self, Self::Err> {
         match rename_all_str {
             "lowercase" => Ok(LowerCase),
+            "UPPERCASE" => Ok(UPPERCASE),
             "PascalCase" => Ok(PascalCase),
             "camelCase" => Ok(CamelCase),
             "snake_case" => Ok(SnakeCase),
@@ -106,10 +111,11 @@ impl FromStr for RenameRule {
 
 #[test]
 fn rename_variants() {
-    for &(original, lower, camel, snake, screaming, kebab, screaming_kebab) in &[
+    for &(original, lower, upper, camel, snake, screaming, kebab, screaming_kebab) in &[
         (
             "Outcome",
             "outcome",
+            "OUTCOME",
             "outcome",
             "outcome",
             "OUTCOME",
@@ -119,17 +125,19 @@ fn rename_variants() {
         (
             "VeryTasty",
             "verytasty",
+            "VERYTASTY",
             "veryTasty",
             "very_tasty",
             "VERY_TASTY",
             "very-tasty",
             "VERY-TASTY",
         ),
-        ("A", "a", "a", "a", "A", "a", "A"),
-        ("Z42", "z42", "z42", "z42", "Z42", "z42", "Z42"),
+        ("A", "a", "A", "a", "a", "A", "a", "A"),
+        ("Z42", "z42", "Z42", "z42", "z42", "Z42", "z42", "Z42"),
     ] {
         assert_eq!(None.apply_to_variant(original), original);
         assert_eq!(LowerCase.apply_to_variant(original), lower);
+        assert_eq!(UPPERCASE.apply_to_variant(original), upper);
         assert_eq!(PascalCase.apply_to_variant(original), original);
         assert_eq!(CamelCase.apply_to_variant(original), camel);
         assert_eq!(SnakeCase.apply_to_variant(original), snake);
@@ -144,9 +152,10 @@ fn rename_variants() {
 
 #[test]
 fn rename_fields() {
-    for &(original, pascal, camel, screaming, kebab, screaming_kebab) in &[
+    for &(original, upper, pascal, camel, screaming, kebab, screaming_kebab) in &[
         (
             "outcome",
+            "OUTCOME",
             "Outcome",
             "outcome",
             "OUTCOME",
@@ -155,16 +164,18 @@ fn rename_fields() {
         ),
         (
             "very_tasty",
+            "VERY_TASTY",
             "VeryTasty",
             "veryTasty",
             "VERY_TASTY",
             "very-tasty",
             "VERY-TASTY",
         ),
-        ("a", "A", "a", "A", "a", "A"),
-        ("z42", "Z42", "z42", "Z42", "z42", "Z42"),
+        ("a", "A", "A", "a", "A", "a", "A"),
+        ("z42", "Z42", "Z42", "z42", "Z42", "z42", "Z42"),
     ] {
         assert_eq!(None.apply_to_field(original), original);
+        assert_eq!(UPPERCASE.apply_to_field(original), upper);
         assert_eq!(PascalCase.apply_to_field(original), pascal);
         assert_eq!(CamelCase.apply_to_field(original), camel);
         assert_eq!(SnakeCase.apply_to_field(original), original);

serde_derive_internals/src/check.rs

@@ -6,29 +6,32 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-use ast::{Body, Container, Style};
-use attr::Identifier;
+use ast::{Data, Container, Style};
+use attr::{Identifier, EnumTag};
 use Ctxt;
 
 /// Cross-cutting checks that require looking at more than a single attrs
 /// object. Simpler checks should happen when parsing and building the attrs.
 pub fn check(cx: &Ctxt, cont: &Container) {
     check_getter(cx, cont);
+    check_flatten(cx, cont);
     check_identifier(cx, cont);
     check_variant_skip_attrs(cx, cont);
+    check_internal_tag_field_name_conflict(cx, cont);
+    check_adjacent_tag_conflict(cx, cont);
 }
 
 /// Getters are only allowed inside structs (not enums) with the `remote`
 /// attribute.
 fn check_getter(cx: &Ctxt, cont: &Container) {
-    match cont.body {
-        Body::Enum(_) => {
-            if cont.body.has_getter() {
+    match cont.data {
+        Data::Enum(_) => {
+            if cont.data.has_getter() {
                 cx.error("#[serde(getter = \"...\")] is not allowed in an enum");
             }
         }
-        Body::Struct(_, _) => {
-            if cont.body.has_getter() && cont.attrs.remote().is_none() {
+        Data::Struct(_, _) => {
+            if cont.data.has_getter() && cont.attrs.remote().is_none() {
                 cx.error(
                     "#[serde(getter = \"...\")] can only be used in structs \
                      that have #[serde(remote = \"...\")]",
@@ -38,6 +41,38 @@ fn check_getter(cx: &Ctxt, cont: &Container) {
     }
 }
 
+/// Flattening has some restrictions we can test.
+fn check_flatten(cx: &Ctxt, cont: &Container) {
+    match cont.data {
+        Data::Enum(_) => {
+            assert!(!cont.attrs.has_flatten());
+        }
+        Data::Struct(_, _) => {
+            for field in cont.data.all_fields() {
+                if !field.attrs.flatten() {
+                    continue;
+                }
+                if field.attrs.skip_serializing() {
+                    cx.error(
+                        "#[serde(flatten] can not be combined with \
+                         #[serde(skip_serializing)]"
+                    );
+                } else if field.attrs.skip_serializing_if().is_some() {
+                    cx.error(
+                        "#[serde(flatten] can not be combined with \
+                         #[serde(skip_serializing_if = \"...\")]"
+                    );
+                } else if field.attrs.skip_deserializing() {
+                    cx.error(
+                        "#[serde(flatten] can not be combined with \
+                         #[serde(skip_deserializing)]"
+                    );
+                }
+            }
+        }
+    }
+}
+
 /// The `other` attribute must be used at most once and it must be the last
 /// variant of an enum that has the `field_identifier` attribute.
 ///
@@ -45,9 +80,9 @@ fn check_getter(cx: &Ctxt, cont: &Container) {
 /// `field_identifier` all but possibly one variant must be unit variants. The
 /// last variant may be a newtype variant which is an implicit "other" case.
 fn check_identifier(cx: &Ctxt, cont: &Container) {
-    let variants = match cont.body {
-        Body::Enum(ref variants) => variants,
-        Body::Struct(_, _) => {
+    let variants = match cont.data {
+        Data::Enum(ref variants) => variants,
+        Data::Struct(_, _) => {
             return;
         }
     };
@@ -102,9 +137,9 @@ fn check_identifier(cx: &Ctxt, cont: &Container) {
 /// Skip-(de)serializing attributes are not allowed on variants marked
 /// (de)serialize_with.
 fn check_variant_skip_attrs(cx: &Ctxt, cont: &Container) {
-    let variants = match cont.body {
-        Body::Enum(ref variants) => variants,
-        Body::Struct(_, _) => {
+    let variants = match cont.data {
+        Data::Enum(ref variants) => variants,
+        Data::Struct(_, _) => {
             return;
         }
     };
@@ -169,3 +204,67 @@ fn check_variant_skip_attrs(cx: &Ctxt, cont: &Container) {
         }
     }
 }
+
+/// The tag of an internally-tagged struct variant must not be
+/// the same as either one of its fields, as this would result in
+/// duplicate keys in the serialized output and/or ambiguity in
+/// the to-be-deserialized input.
+fn check_internal_tag_field_name_conflict(
+    cx: &Ctxt,
+    cont: &Container,
+) {
+    let variants = match cont.data {
+        Data::Enum(ref variants) => variants,
+        Data::Struct(_, _) => return,
+    };
+
+    let tag = match *cont.attrs.tag() {
+        EnumTag::Internal { ref tag } => tag.as_str(),
+        EnumTag::External | EnumTag::Adjacent { .. } | EnumTag::None => return,
+    };
+
+    let diagnose_conflict = || {
+        let message = format!(
+            "variant field name `{}` conflicts with internal tag",
+            tag
+        );
+        cx.error(message);
+    };
+
+    for variant in variants {
+        match variant.style {
+            Style::Struct => {
+                for field in &variant.fields {
+                    let check_ser = !field.attrs.skip_serializing();
+                    let check_de = !field.attrs.skip_deserializing();
+                    let name = field.attrs.name();
+                    let ser_name = name.serialize_name();
+                    let de_name = name.deserialize_name();
+
+                    if check_ser && ser_name == tag || check_de && de_name == tag {
+                        diagnose_conflict();
+                        return;
+                    }
+                }
+            },
+            Style::Unit | Style::Newtype | Style::Tuple => {},
+        }
+    }
+}
+
+/// In the case of adjacently-tagged enums, the type and the
+/// contents tag must differ, for the same reason.
+fn check_adjacent_tag_conflict(cx: &Ctxt, cont: &Container) {
+    let (type_tag, content_tag) = match *cont.attrs.tag() {
+        EnumTag::Adjacent { ref tag, ref content } => (tag, content),
+        EnumTag::Internal { .. } | EnumTag::External | EnumTag::None => return,
+    };
+
+    if type_tag == content_tag {
+        let message = format!(
+            "enum tags `{}` for type and content conflict with each other",
+            type_tag
+        );
+        cx.error(message);
+    }
+}

serde_derive_internals/src/ctxt.rs

@@ -8,6 +8,7 @@
 
 use std::fmt::Display;
 use std::cell::RefCell;
+use std::thread;
 
 #[derive(Default)]
 pub struct Ctxt {
@@ -48,7 +49,7 @@ impl Ctxt {
 
 impl Drop for Ctxt {
     fn drop(&mut self) {
-        if self.errors.borrow().is_some() {
+        if !thread::panicking() && self.errors.borrow().is_some() {
             panic!("forgot to check for errors");
         }
     }

serde_derive_internals/src/lib.rs

@@ -6,11 +6,14 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-#![doc(html_root_url = "https://docs.rs/serde_derive_internals/0.18.1")]
+#![doc(html_root_url = "https://docs.rs/serde_derive_internals/0.22.1")]
+#![cfg_attr(feature = "cargo-clippy", allow(cyclomatic_complexity, doc_markdown, match_same_arms,
+                                            redundant_field_names))]
 
-extern crate syn;
 #[macro_use]
-extern crate synom;
+extern crate syn;
+
+extern crate proc_macro2;
 
 pub mod ast;
 pub mod attr;

serde_test/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "serde_test"
-version = "1.0.25" # remember to update html_root_url
+version = "1.0.35" # 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/lib.rs

@@ -53,7 +53,7 @@
 //! # use serde::ser::{Serialize, Serializer, SerializeMap};
 //! # use serde::de::{Deserialize, Deserializer, Visitor, MapAccess};
 //! #
-//! # // Dumb immitation of LinkedHashMap.
+//! # // Dumb imitation of LinkedHashMap.
 //! # #[derive(PartialEq, Debug)]
 //! # struct LinkedHashMap<K, V>(Vec<(K, V)>);
 //! #
@@ -155,13 +155,14 @@
 //! # }
 //! ```
 
-#![doc(html_root_url = "https://docs.rs/serde_test/1.0.25")]
+#![doc(html_root_url = "https://docs.rs/serde_test/1.0.35")]
 #![cfg_attr(feature = "cargo-clippy", deny(clippy, clippy_pedantic))]
 // Whitelisted clippy lints
 #![cfg_attr(feature = "cargo-clippy", allow(float_cmp))]
 // Whitelisted clippy_pedantic lints
 #![cfg_attr(feature = "cargo-clippy",
-            allow(missing_docs_in_private_items, stutter, use_debug, use_self))]
+            allow(empty_line_after_outer_attr, missing_docs_in_private_items,
+                  redundant_field_names, stutter, use_debug, use_self))]
 
 #[macro_use]
 extern crate serde;

test_suite/Cargo.toml

@@ -9,6 +9,7 @@ unstable = ["serde/unstable", "compiletest_rs"]
 
 [dev-dependencies]
 fnv = "1.0"
+proc-macro2 = "0.2"
 rustc-serialize = "0.3.16"
 serde = { path = "../serde", features = ["rc"] }
 serde_derive = { path = "../serde_derive", features = ["deserialize_in_place"] }

test_suite/tests/compile-fail/conflict/adjacent-tag.rs

@@ -0,0 +1,20 @@
+// Copyright 2018 Serde Developers
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+#[macro_use]
+extern crate serde_derive;
+
+#[derive(Serialize)] //~ ERROR: proc-macro derive panicked
+#[serde(tag = "conflict", content = "conflict")]
+//~^^ HELP: enum tags `conflict` for type and content conflict with each other
+enum E {
+    A,
+    B,
+}
+
+fn main() {}

test_suite/tests/compile-fail/conflict/flatten-skip-deserializing.rs

@@ -0,0 +1,24 @@
+// Copyright 2018 Serde Developers
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+#[macro_use]
+extern crate serde_derive;
+
+#[derive(Deserialize)] //~ ERROR: proc-macro derive panicked
+//~^ HELP: #[serde(flatten] can not be combined with #[serde(skip_deserializing)]
+struct Foo {
+    #[serde(flatten, skip_deserializing)]
+    other: Other,
+}
+
+#[derive(Deserialize)]
+struct Other {
+    x: u32
+}
+
+fn main() {}

test_suite/tests/compile-fail/conflict/flatten-skip-serializing-if.rs

@@ -0,0 +1,24 @@
+// Copyright 2018 Serde Developers
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+#[macro_use]
+extern crate serde_derive;
+
+#[derive(Serialize)] //~ ERROR: proc-macro derive panicked
+//~^ HELP: #[serde(flatten] can not be combined with #[serde(skip_serializing_if = "...")]
+struct Foo {
+    #[serde(flatten, skip_serializing_if="Option::is_none")]
+    other: Option<Other>,
+}
+
+#[derive(Serialize)]
+struct Other {
+    x: u32
+}
+
+fn main() {}

test_suite/tests/compile-fail/conflict/flatten-skip-serializing.rs

@@ -0,0 +1,24 @@
+// Copyright 2018 Serde Developers
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+#[macro_use]
+extern crate serde_derive;
+
+#[derive(Serialize)] //~ ERROR: proc-macro derive panicked
+//~^ HELP: #[serde(flatten] can not be combined with #[serde(skip_serializing)]
+struct Foo {
+    #[serde(flatten, skip_serializing)]
+    other: Other,
+}
+
+#[derive(Serialize)]
+struct Other {
+    x: u32
+}
+
+fn main() {}

test_suite/tests/compile-fail/conflict/internal-tag.rs

@@ -0,0 +1,22 @@
+// Copyright 2018 Serde Developers
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+#[macro_use]
+extern crate serde_derive;
+
+#[derive(Serialize)] //~ ERROR: proc-macro derive panicked
+#[serde(tag = "conflict")]
+//~^^ HELP: variant field name `conflict` conflicts with internal tag
+enum E {
+    A {
+        #[serde(rename = "conflict")]
+        x: (),
+    },
+}
+
+fn main() {}

test_suite/tests/test_annotations.rs

@@ -12,12 +12,13 @@
 extern crate serde_derive;
 
 extern crate serde;
+use std::collections::HashMap;
 use self::serde::{Deserialize, Deserializer, Serialize, Serializer};
 use self::serde::de::{self, Unexpected};
 
 extern crate serde_test;
-use self::serde_test::{assert_de_tokens, assert_de_tokens_error, assert_ser_tokens, assert_tokens,
-                       Token};
+use self::serde_test::{assert_de_tokens, assert_de_tokens_error, assert_ser_tokens,
+                       assert_ser_tokens_error, assert_tokens, Token};
 
 trait MyDefault: Sized {
     fn my_default() -> Self;
@@ -94,6 +95,56 @@ where
     a5: E,
 }
 
+#[derive(Debug, PartialEq, Serialize, Deserialize)]
+struct CollectOther {
+    a: u32,
+    b: u32,
+    #[serde(flatten)]
+    extra: HashMap<String, u32>,
+}
+
+#[derive(Debug, PartialEq, Serialize, Deserialize)]
+struct FlattenStructEnumWrapper {
+    #[serde(flatten)]
+    data: FlattenStructEnum,
+    #[serde(flatten)]
+    extra: HashMap<String, String>,
+}
+
+#[derive(Debug, PartialEq, Serialize, Deserialize)]
+#[serde(rename_all = "snake_case")]
+enum FlattenStructEnum {
+    InsertInteger {
+        index: u32,
+        value: u32
+    },
+}
+
+#[derive(Debug, PartialEq, Serialize, Deserialize)]
+struct FlattenStructTagContentEnumWrapper {
+    outer: u32,
+    #[serde(flatten)]
+    data: FlattenStructTagContentEnumNewtype,
+}
+
+#[derive(Debug, PartialEq, Serialize, Deserialize)]
+struct FlattenStructTagContentEnumNewtype(pub FlattenStructTagContentEnum);
+
+#[derive(Debug, PartialEq, Serialize, Deserialize)]
+#[serde(rename_all = "snake_case", tag = "type", content = "value")]
+enum FlattenStructTagContentEnum {
+    InsertInteger {
+        index: u32,
+        value: u32
+    },
+    NewtypeVariant(FlattenStructTagContentEnumNewtypeVariant),
+}
+
+#[derive(Debug, PartialEq, Serialize, Deserialize)]
+struct FlattenStructTagContentEnumNewtypeVariant {
+    value: u32,
+}
+
 #[test]
 fn test_default_struct() {
     assert_de_tokens(
@@ -1267,3 +1318,482 @@ fn test_from_into_traits() {
     assert_ser_tokens::<StructFromEnum>(&StructFromEnum(None), &[Token::None]);
     assert_de_tokens::<StructFromEnum>(&StructFromEnum(Some(2)), &[Token::Some, Token::U32(2)]);
 }
+
+#[test]
+fn test_collect_other() {
+    let mut extra = HashMap::new();
+    extra.insert("c".into(), 3);
+    assert_tokens(
+        &CollectOther { a: 1, b: 2, extra },
+        &[
+            Token::Map { len: None },
+            Token::Str("a"),
+            Token::U32(1),
+            Token::Str("b"),
+            Token::U32(2),
+            Token::Str("c"),
+            Token::U32(3),
+            Token::MapEnd,
+        ],
+    );
+}
+
+#[test]
+fn test_flatten_struct_enum() {
+    let mut extra = HashMap::new();
+    extra.insert("extra_key".into(), "extra value".into());
+    let change_request = FlattenStructEnumWrapper {
+        data: FlattenStructEnum::InsertInteger {
+            index: 0,
+            value: 42
+        },
+        extra,
+    };
+    assert_de_tokens(
+        &change_request,
+        &[
+            Token::Map { len: None },
+            Token::Str("insert_integer"),
+            Token::Map { len: None },
+            Token::Str("index"),
+            Token::U32(0),
+            Token::Str("value"),
+            Token::U32(42),
+            Token::MapEnd,
+            Token::Str("extra_key"),
+            Token::Str("extra value"),
+            Token::MapEnd
+        ],
+    );
+    assert_ser_tokens(
+        &change_request,
+        &[
+            Token::Map { len: None },
+            Token::Str("insert_integer"),
+            Token::Struct { len: 2, name: "insert_integer" },
+            Token::Str("index"),
+            Token::U32(0),
+            Token::Str("value"),
+            Token::U32(42),
+            Token::StructEnd,
+            Token::Str("extra_key"),
+            Token::Str("extra value"),
+            Token::MapEnd
+        ],
+    );
+}
+
+#[test]
+fn test_flatten_struct_tag_content_enum() {
+    let change_request = FlattenStructTagContentEnumWrapper {
+        outer: 42,
+        data: FlattenStructTagContentEnumNewtype(
+            FlattenStructTagContentEnum::InsertInteger {
+                index: 0,
+                value: 42
+            }
+        ),
+    };
+    assert_de_tokens(
+        &change_request,
+        &[
+            Token::Map { len: None },
+            Token::Str("outer"),
+            Token::U32(42),
+            Token::Str("type"),
+            Token::Str("insert_integer"),
+            Token::Str("value"),
+            Token::Map { len: None },
+            Token::Str("index"),
+            Token::U32(0),
+            Token::Str("value"),
+            Token::U32(42),
+            Token::MapEnd,
+            Token::MapEnd,
+        ],
+    );
+    assert_ser_tokens(
+        &change_request,
+        &[
+            Token::Map { len: None },
+            Token::Str("outer"),
+            Token::U32(42),
+            Token::Str("type"),
+            Token::Str("insert_integer"),
+            Token::Str("value"),
+            Token::Struct { len: 2, name: "insert_integer" },
+            Token::Str("index"),
+            Token::U32(0),
+            Token::Str("value"),
+            Token::U32(42),
+            Token::StructEnd,
+            Token::MapEnd,
+        ],
+    );
+}
+
+#[test]
+fn test_flatten_struct_tag_content_enum_newtype() {
+    let change_request = FlattenStructTagContentEnumWrapper {
+        outer: 42,
+        data: FlattenStructTagContentEnumNewtype(
+            FlattenStructTagContentEnum::NewtypeVariant(
+                FlattenStructTagContentEnumNewtypeVariant {
+                    value: 23
+                }
+            )
+        ),
+    };
+    assert_de_tokens(
+        &change_request,
+        &[
+            Token::Map { len: None },
+            Token::Str("outer"),
+            Token::U32(42),
+            Token::Str("type"),
+            Token::Str("newtype_variant"),
+            Token::Str("value"),
+            Token::Map { len: None },
+            Token::Str("value"),
+            Token::U32(23),
+            Token::MapEnd,
+            Token::MapEnd,
+        ],
+    );
+    assert_ser_tokens(
+        &change_request,
+        &[
+            Token::Map { len: None },
+            Token::Str("outer"),
+            Token::U32(42),
+            Token::Str("type"),
+            Token::Str("newtype_variant"),
+            Token::Str("value"),
+            Token::Struct { len: 1, name: "FlattenStructTagContentEnumNewtypeVariant" },
+            Token::Str("value"),
+            Token::U32(23),
+            Token::StructEnd,
+            Token::MapEnd,
+        ],
+    );
+}
+
+#[test]
+fn test_unknown_field_in_flatten() {
+    #[derive(Debug, PartialEq, Serialize, Deserialize)]
+    #[serde(deny_unknown_fields)]
+    struct Outer {
+        dummy: String,
+        #[serde(flatten)]
+        inner: Inner,
+    }
+
+    #[derive(Debug, PartialEq, Serialize, Deserialize)]
+    struct Inner {
+        foo: HashMap<String, u32>,
+    }
+
+    assert_de_tokens_error::<Outer>(
+        &[
+            Token::Struct {
+                name: "Outer",
+                len: 1,
+            },
+            Token::Str("dummy"),
+            Token::Str("23"),
+            Token::Str("foo"),
+            Token::Map { len: None },
+            Token::Str("a"),
+            Token::U32(1),
+            Token::Str("b"),
+            Token::U32(2),
+            Token::MapEnd,
+            Token::Str("bar"),
+            Token::U32(23),
+            Token::StructEnd,
+        ],
+        "unknown field `bar`",
+    );
+}
+
+#[test]
+fn test_complex_flatten() {
+    #[derive(Debug, PartialEq, Serialize, Deserialize)]
+    struct Outer {
+        y: u32,
+        #[serde(flatten)]
+        first: First,
+        #[serde(flatten)]
+        second: Second,
+        z: u32
+    }
+
+    #[derive(Debug, PartialEq, Serialize, Deserialize)]
+    struct First {
+        a: u32,
+        b: bool,
+        c: Vec<String>,
+        d: String,
+        e: Option<u64>,
+    }
+
+    #[derive(Debug, PartialEq, Serialize, Deserialize)]
+    struct Second {
+        f: u32,
+    }
+
+    assert_de_tokens(
+        &Outer {
+            y: 0,
+            first: First {
+                a: 1,
+                b: true,
+                c: vec!["a".into(), "b".into()],
+                d: "c".into(),
+                e: Some(2),
+            },
+            second: Second {
+                f: 3
+            },
+            z: 4
+        },
+        &[
+            Token::Map { len: None },
+            Token::Str("y"),
+            Token::U32(0),
+            Token::Str("a"),
+            Token::U32(1),
+            Token::Str("b"),
+            Token::Bool(true),
+            Token::Str("c"),
+            Token::Seq { len: Some(2) },
+            Token::Str("a"),
+            Token::Str("b"),
+            Token::SeqEnd,
+            Token::Str("d"),
+            Token::Str("c"),
+            Token::Str("e"),
+            Token::U64(2),
+            Token::Str("f"),
+            Token::U32(3),
+            Token::Str("z"),
+            Token::U32(4),
+            Token::MapEnd,
+        ],
+    );
+
+    assert_ser_tokens(
+        &Outer {
+            y: 0,
+            first: First {
+                a: 1,
+                b: true,
+                c: vec!["a".into(), "b".into()],
+                d: "c".into(),
+                e: Some(2),
+            },
+            second: Second {
+                f: 3
+            },
+            z: 4
+        },
+        &[
+            Token::Map { len: None },
+            Token::Str("y"),
+            Token::U32(0),
+            Token::Str("a"),
+            Token::U32(1),
+            Token::Str("b"),
+            Token::Bool(true),
+            Token::Str("c"),
+            Token::Seq { len: Some(2) },
+            Token::Str("a"),
+            Token::Str("b"),
+            Token::SeqEnd,
+            Token::Str("d"),
+            Token::Str("c"),
+            Token::Str("e"),
+            Token::Some,
+            Token::U64(2),
+            Token::Str("f"),
+            Token::U32(3),
+            Token::Str("z"),
+            Token::U32(4),
+            Token::MapEnd,
+        ],
+    );
+}
+
+#[test]
+fn test_flatten_unsupported_type() {
+    #[derive(Debug, PartialEq, Serialize, Deserialize)]
+    struct Outer {
+        outer: String,
+        #[serde(flatten)]
+        inner: String,
+    }
+
+    assert_ser_tokens_error(
+        &Outer {
+            outer: "foo".into(),
+            inner: "bar".into(),
+        },
+        &[
+            Token::Map { len: None },
+            Token::Str("outer"),
+            Token::Str("foo"),
+        ],
+        "can only flatten structs and maps (got a string)",
+    );
+    assert_de_tokens_error::<Outer>(
+        &[
+            Token::Map { len: None },
+            Token::Str("outer"),
+            Token::Str("foo"),
+            Token::Str("a"),
+            Token::Str("b"),
+            Token::MapEnd
+        ],
+        "can only flatten structs and maps",
+    );
+}
+
+#[test]
+fn test_non_string_keys() {
+    #[derive(Debug, PartialEq, Serialize, Deserialize)]
+    struct TestStruct {
+        name: String,
+        age: u32,
+        #[serde(flatten)]
+        mapping: HashMap<u32, u32>,
+    }
+
+    let mut mapping = HashMap::new();
+    mapping.insert(0, 42);
+    assert_tokens(
+        &TestStruct { name: "peter".into(), age: 3, mapping },
+        &[
+            Token::Map { len: None },
+            Token::Str("name"),
+            Token::Str("peter"),
+            Token::Str("age"),
+            Token::U32(3),
+            Token::U32(0),
+            Token::U32(42),
+            Token::MapEnd,
+        ],
+    );
+}
+
+#[test]
+fn test_lifetime_propagation_for_flatten() {
+    #[derive(Deserialize, Serialize, Debug, PartialEq)]
+    struct A<T> {
+        #[serde(flatten)]
+        t: T,
+    }
+
+    #[derive(Deserialize, Serialize, Debug, PartialEq)]
+    struct B<'a> {
+        #[serde(flatten, borrow)]
+        t: HashMap<&'a str, u32>,
+    }
+
+    #[derive(Deserialize, Serialize, Debug, PartialEq)]
+    struct C<'a> {
+        #[serde(flatten, borrow)]
+        t: HashMap<&'a [u8], u32>,
+    }
+
+    let mut owned_map = HashMap::new();
+    owned_map.insert("x".to_string(), 42u32);
+    assert_tokens(
+        &A { t: owned_map },
+        &[
+            Token::Map { len: None },
+            Token::Str("x"),
+            Token::U32(42),
+            Token::MapEnd,
+        ],
+    );
+
+    let mut borrowed_map = HashMap::new();
+    borrowed_map.insert("x", 42u32);
+    assert_ser_tokens(
+        &B { t: borrowed_map.clone() },
+        &[
+            Token::Map { len: None },
+            Token::BorrowedStr("x"),
+            Token::U32(42),
+            Token::MapEnd,
+        ],
+    );
+
+    assert_de_tokens(
+        &B { t: borrowed_map },
+        &[
+            Token::Map { len: None },
+            Token::BorrowedStr("x"),
+            Token::U32(42),
+            Token::MapEnd,
+        ],
+    );
+
+    let mut borrowed_map = HashMap::new();
+    borrowed_map.insert(&b"x"[..], 42u32);
+    assert_ser_tokens(
+        &C { t: borrowed_map.clone() },
+        &[
+            Token::Map { len: None },
+            Token::Seq { len: Some(1) },
+            Token::U8(120),
+            Token::SeqEnd,
+            Token::U32(42),
+            Token::MapEnd,
+        ],
+    );
+
+    assert_de_tokens(
+        &C { t: borrowed_map },
+        &[
+            Token::Map { len: None },
+            Token::BorrowedBytes(b"x"),
+            Token::U32(42),
+            Token::MapEnd,
+        ],
+    );
+}
+
+#[test]
+fn test_flatten_enum_newtype() {
+    #[derive(Serialize, Deserialize, PartialEq, Debug)]
+    struct S {
+        #[serde(flatten)]
+        flat: E,
+    }
+
+    #[derive(Serialize, Deserialize, PartialEq, Debug)]
+    enum E {
+        Q(HashMap<String, String>),
+    }
+
+    let e = E::Q({
+        let mut map = HashMap::new();
+        map.insert("k".to_owned(), "v".to_owned());
+        map
+    });
+    let s = S { flat: e };
+
+    assert_tokens(
+        &s,
+        &[
+            Token::Map { len: None },
+            Token::Str("Q"),
+            Token::Map { len: Some(1) },
+            Token::Str("k"),
+            Token::Str("v"),
+            Token::MapEnd,
+            Token::MapEnd,
+        ],
+    );
+}

test_suite/tests/test_de.rs

@@ -6,6 +6,8 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+#![cfg_attr(feature = "cargo-clippy", allow(decimal_literal_representation))]
+
 #[macro_use]
 extern crate serde_derive;
 

test_suite/tests/test_gen.rs

@@ -528,6 +528,13 @@ fn test_gen() {
         marker: PhantomData<T>,
     }
     assert::<TypeMacro<X>>();
+
+    #[derive(Serialize)]
+    struct BigArray {
+        #[serde(serialize_with = "<[_]>::serialize")]
+        array: [u8; 256],
+    }
+    assert_ser::<BigArray>();
 }
 
 //////////////////////////////////////////////////////////////////////////

test_suite/tests/test_macros.rs

@@ -8,6 +8,8 @@
 
 #![deny(trivial_numeric_casts)]
 
+#![cfg_attr(feature = "cargo-clippy", allow(redundant_field_names))]
+
 #[macro_use]
 extern crate serde_derive;
 

test_suite/tests/test_remote.rs

@@ -6,6 +6,8 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+#![cfg_attr(feature = "cargo-clippy", allow(redundant_field_names))]
+
 #[macro_use]
 extern crate serde_derive;
 

test_suite/tests/test_roundtrip.rs

@@ -30,7 +30,7 @@ fn ip_addr_roundtrip() {
 }
 
 #[test]
-fn socked_addr_roundtrip() {
+fn socket_addr_roundtrip() {
     assert_tokens(
         &net::SocketAddr::from((*b"1234567890123456", 1234)).compact(),
         &seq![

travis.sh

@@ -55,6 +55,7 @@ else
     channel build
     cd "$DIR/test_suite"
     channel test --features unstable
+    channel build --tests --features proc-macro2/nightly
     if [ -z "${APPVEYOR}" ]; then
         cd "$DIR/test_suite/no_std"
         channel build