Release 1.0.149

Remove some Serialize trait bounds

.github/workflows/ci.yml

@@ -5,6 +5,9 @@ on:
   pull_request:
   schedule: [cron: "40 1 * * *"]
 
+permissions:
+  contents: read
+
 env:
   RUSTFLAGS: -Dwarnings
 
@@ -12,6 +15,7 @@ jobs:
   test:
     name: Test suite
     runs-on: ubuntu-latest
+    timeout-minutes: 45
     steps:
       - uses: actions/checkout@v3
       - uses: dtolnay/rust-toolchain@nightly
@@ -24,6 +28,7 @@ jobs:
   windows:
     name: Test suite (windows)
     runs-on: windows-latest
+    timeout-minutes: 45
     steps:
       - uses: actions/checkout@v3
       - uses: dtolnay/rust-toolchain@nightly
@@ -36,6 +41,7 @@ jobs:
       fail-fast: false
       matrix:
         rust: [stable, beta]
+    timeout-minutes: 45
     steps:
       - uses: actions/checkout@v3
       - uses: dtolnay/rust-toolchain@master
@@ -53,6 +59,7 @@ jobs:
       fail-fast: false
       matrix:
         os: [ubuntu, windows]
+    timeout-minutes: 45
     steps:
       - uses: actions/checkout@v3
       - uses: dtolnay/rust-toolchain@nightly
@@ -71,12 +78,13 @@ jobs:
   msrv:
     name: Rust 1.13.0
     runs-on: ubuntu-latest
+    timeout-minutes: 45
     steps:
       - uses: actions/checkout@v3
       - uses: dtolnay/rust-toolchain@1.13.0
       - name: Get timestamp for cache
         id: date
-        run: echo ::set-output name=yearmo::$(date +%Y%m)
+        run: echo yearmo=$(date +%Y%m) >> $GITHUB_OUTPUT
       - uses: actions/cache@v1
         with:
           path: ~/.cargo/registry/index
@@ -92,6 +100,7 @@ jobs:
       fail-fast: false
       matrix:
         rust: [1.19.0, 1.20.0, 1.21.0, 1.25.0, 1.26.0, 1.34.0]
+    timeout-minutes: 45
     steps:
       - uses: actions/checkout@v3
       - uses: dtolnay/rust-toolchain@master
@@ -107,6 +116,7 @@ jobs:
       fail-fast: false
       matrix:
         rust: [1.27.0, 1.28.0]
+    timeout-minutes: 45
     steps:
       - uses: actions/checkout@v3
       - uses: dtolnay/rust-toolchain@master
@@ -120,6 +130,7 @@ jobs:
   derive:
     name: Rust 1.31.0
     runs-on: ubuntu-latest
+    timeout-minutes: 45
     steps:
       - uses: actions/checkout@v3
       - uses: dtolnay/rust-toolchain@1.31.0
@@ -130,6 +141,7 @@ jobs:
   alloc:
     name: Rust 1.36.0
     runs-on: ubuntu-latest
+    timeout-minutes: 45
     steps:
       - uses: actions/checkout@v3
       - uses: dtolnay/rust-toolchain@1.36.0
@@ -138,6 +150,7 @@ jobs:
   emscripten:
     name: Emscripten
     runs-on: ubuntu-latest
+    timeout-minutes: 45
     steps:
       - uses: actions/checkout@v3
       - uses: dtolnay/rust-toolchain@nightly
@@ -161,6 +174,7 @@ jobs:
     name: Clippy
     runs-on: ubuntu-latest
     if: github.event_name != 'pull_request'
+    timeout-minutes: 45
     steps:
       - uses: actions/checkout@v3
       - uses: dtolnay/rust-toolchain@clippy
@@ -174,6 +188,7 @@ jobs:
   miri:
     name: Miri
     runs-on: ubuntu-latest
+    timeout-minutes: 45
     steps:
       - uses: actions/checkout@v3
       - uses: dtolnay/rust-toolchain@miri
@@ -188,6 +203,7 @@ jobs:
     name: Outdated
     runs-on: ubuntu-latest
     if: github.event_name != 'pull_request'
+    timeout-minutes: 45
     steps:
       - uses: actions/checkout@v3
       - uses: dtolnay/install@cargo-outdated

serde/Cargo.toml

@@ -1,21 +1,21 @@
 [package]
 name = "serde"
-version = "1.0.137" # remember to update html_root_url and serde_derive dependency
+version = "1.0.149" # remember to update html_root_url and serde_derive dependency
 authors = ["Erick Tryzelaar <erick.tryzelaar@gmail.com>", "David Tolnay <dtolnay@gmail.com>"]
-rust-version = "1.13"
-license = "MIT OR Apache-2.0"
-description = "A generic serialization/deserialization framework"
-homepage = "https://serde.rs"
-repository = "https://github.com/serde-rs/serde"
-documentation = "https://docs.serde.rs/serde/"
-keywords = ["serde", "serialization", "no_std"]
-categories = ["encoding"]
-readme = "crates-io.md"
-include = ["build.rs", "src/**/*.rs", "crates-io.md", "README.md", "LICENSE-APACHE", "LICENSE-MIT"]
 build = "build.rs"
+categories = ["encoding", "no-std"]
+description = "A generic serialization/deserialization framework"
+documentation = "https://docs.serde.rs/serde/"
+homepage = "https://serde.rs"
+include = ["build.rs", "src/**/*.rs", "crates-io.md", "README.md", "LICENSE-APACHE", "LICENSE-MIT"]
+keywords = ["serde", "serialization", "no_std"]
+license = "MIT OR Apache-2.0"
+readme = "crates-io.md"
+repository = "https://github.com/serde-rs/serde"
+rust-version = "1.13"
 
 [dependencies]
-serde_derive = { version = "=1.0.137", optional = true, path = "../serde_derive" }
+serde_derive = { version = "=1.0.149", optional = true, path = "../serde_derive" }
 
 [dev-dependencies]
 serde_derive = { version = "1.0", path = "../serde_derive" }

serde/build.rs

@@ -89,6 +89,7 @@ fn main() {
         println!("cargo:rustc-cfg=no_core_try_from");
         println!("cargo:rustc-cfg=no_num_nonzero_signed");
         println!("cargo:rustc-cfg=no_systemtime_checked_add");
+        println!("cargo:rustc-cfg=no_relaxed_trait_bounds");
     }
 
     // Whitelist of archs that support std::sync::atomic module. Ideally we

serde/src/de/format.rs

@@ -1,7 +1,7 @@
 use lib::fmt::{self, Write};
 use lib::str;
 
-pub struct Buf<'a> {
+pub(super) struct Buf<'a> {
     bytes: &'a mut [u8],
     offset: usize,
 }

serde/src/de/ignored_any.rs

@@ -228,7 +228,7 @@ impl<'de> Visitor<'de> for IgnoredAny {
     where
         A: EnumAccess<'de>,
     {
-        data.variant::<IgnoredAny>()?.1.newtype_variant()
+        try!(data.variant::<IgnoredAny>()).1.newtype_variant()
     }
 }
 

serde/src/de/impls.rs

@@ -2268,14 +2268,14 @@ where
     where
         D: Deserializer<'de>,
     {
-        let (start, end) = deserializer.deserialize_struct(
+        let (start, end) = try!(deserializer.deserialize_struct(
             "Range",
             range::FIELDS,
             range::RangeVisitor {
                 expecting: "struct Range",
                 phantom: PhantomData,
             },
-        )?;
+        ));
         Ok(start..end)
     }
 }
@@ -2289,14 +2289,14 @@ where
     where
         D: Deserializer<'de>,
     {
-        let (start, end) = deserializer.deserialize_struct(
+        let (start, end) = try!(deserializer.deserialize_struct(
             "RangeInclusive",
             range::FIELDS,
             range::RangeVisitor {
                 expecting: "struct RangeInclusive",
                 phantom: PhantomData,
             },
-        )?;
+        ));
         Ok(RangeInclusive::new(start, end))
     }
 }

serde/src/de/mod.rs

@@ -30,7 +30,7 @@
 //! # The Deserializer trait
 //!
 //! [`Deserializer`] implementations are provided by third-party crates, for
-//! example [`serde_json`], [`serde_yaml`] and [`bincode`].
+//! example [`serde_json`], [`serde_yaml`] and [`postcard`].
 //!
 //! A partial list of well-maintained formats is given on the [Serde
 //! website][data formats].
@@ -104,7 +104,7 @@
 //! [`Deserialize`]: ../trait.Deserialize.html
 //! [`Deserializer`]: ../trait.Deserializer.html
 //! [`LinkedHashMap<K, V>`]: https://docs.rs/linked-hash-map/*/linked_hash_map/struct.LinkedHashMap.html
-//! [`bincode`]: https://github.com/bincode-org/bincode
+//! [`postcard`]: https://github.com/jamesmunns/postcard
 //! [`linked-hash-map`]: https://crates.io/crates/linked-hash-map
 //! [`serde_derive`]: https://crates.io/crates/serde_derive
 //! [`serde_json`]: https://github.com/serde-rs/json
@@ -565,7 +565,7 @@ pub trait Deserialize<'de>: Sized {
         D: Deserializer<'de>,
     {
         // Default implementation just delegates to `deserialize` impl.
-        *place = Deserialize::deserialize(deserializer)?;
+        *place = try!(Deserialize::deserialize(deserializer));
         Ok(())
     }
 }
@@ -708,6 +708,11 @@ impl<T> DeserializeOwned for T where T: for<'de> Deserialize<'de> {}
 ///             where
 ///                 A: SeqAccess<'de>,
 ///             {
+///                 // Decrease the number of reallocations if there are many elements
+///                 if let Some(size_hint) = seq.size_hint() {
+///                    self.0.reserve(size_hint);
+///                 }
+///
 ///                 // Visit each element in the inner array and push it onto
 ///                 // the existing vector.
 ///                 while let Some(elem) = seq.next_element()? {
@@ -857,10 +862,10 @@ where
 /// The `Deserializer` trait supports two entry point styles which enables
 /// different kinds of deserialization.
 ///
-/// 1. The `deserialize` method. Self-describing data formats like JSON are able
+/// 1. The `deserialize_any` method. Self-describing data formats like JSON are
-///    to look at the serialized data and tell what it represents. For example
+///    able to look at the serialized data and tell what it represents. For
-///    the JSON deserializer may see an opening curly brace (`{`) and know that
+///    example the JSON deserializer may see an opening curly brace (`{`) and
-///    it is seeing a map. If the data format supports
+///    know that it is seeing a map. If the data format supports
 ///    `Deserializer::deserialize_any`, it will drive the Visitor using whatever
 ///    type it sees in the input. JSON uses this approach when deserializing
 ///    `serde_json::Value` which is an enum that can represent any JSON
@@ -869,7 +874,7 @@ where
 ///    `Deserializer::deserialize_any`.
 ///
 /// 2. The various `deserialize_*` methods. Non-self-describing formats like
-///    Bincode need to be told what is in the input in order to deserialize it.
+///    Postcard need to be told what is in the input in order to deserialize it.
 ///    The `deserialize_*` methods are hints to the deserializer for how to
 ///    interpret the next piece of input. Non-self-describing formats are not
 ///    able to deserialize something like `serde_json::Value` which relies on
@@ -879,7 +884,7 @@ where
 /// `Deserializer::deserialize_any` unless you need to be told by the
 /// Deserializer what type is in the input. Know that relying on
 /// `Deserializer::deserialize_any` means your data type will be able to
-/// deserialize from self-describing formats only, ruling out Bincode and many
+/// deserialize from self-describing formats only, ruling out Postcard and many
 /// others.
 ///
 /// [Serde data model]: https://serde.rs/data-model.html
@@ -910,7 +915,7 @@ pub trait Deserializer<'de>: Sized {
     /// `Deserializer::deserialize_any` unless you need to be told by the
     /// Deserializer what type is in the input. Know that relying on
     /// `Deserializer::deserialize_any` means your data type will be able to
-    /// deserialize from self-describing formats only, ruling out Bincode and
+    /// deserialize from self-describing formats only, ruling out Postcard and
     /// many others.
     fn deserialize_any<V>(self, visitor: V) -> Result<V::Value, Self::Error>
     where
@@ -1151,7 +1156,7 @@ pub trait Deserializer<'de>: Sized {
     /// Some types have a human-readable form that may be somewhat expensive to
     /// construct, as well as a binary form that is compact and efficient.
     /// Generally text-based formats like JSON and YAML will prefer to use the
-    /// human-readable one and binary formats like Bincode will prefer the
+    /// human-readable one and binary formats like Postcard will prefer the
     /// compact one.
     ///
     /// ```edition2018
@@ -1555,7 +1560,7 @@ pub trait Visitor<'de>: Sized {
     /// `Deserializer`.
     ///
     /// This enables zero-copy deserialization of bytes in some formats. For
-    /// example Bincode data containing bytes can be deserialized with zero
+    /// example Postcard data containing bytes can be deserialized with zero
     /// copying into a `&'a [u8]` as long as the input data outlives `'a`.
     ///
     /// The default implementation forwards to `visit_bytes`.

serde/src/de/value.rs

@@ -128,9 +128,7 @@ where
     type Deserializer = UnitDeserializer<E>;
 
     fn into_deserializer(self) -> UnitDeserializer<E> {
-        UnitDeserializer {
+        UnitDeserializer::new()
-            marker: PhantomData,
-        }
     }
 }
 
@@ -141,6 +139,15 @@ pub struct UnitDeserializer<E> {
 
 impl_copy_clone!(UnitDeserializer);
 
+impl<E> UnitDeserializer<E> {
+    #[allow(missing_docs)]
+    pub fn new() -> Self {
+        UnitDeserializer {
+            marker: PhantomData,
+        }
+    }
+}
+
 impl<'de, E> de::Deserializer<'de> for UnitDeserializer<E>
 where
     E: de::Error,
@@ -236,8 +243,15 @@ macro_rules! primitive_deserializer {
             type Deserializer = $name<E>;
 
             fn into_deserializer(self) -> $name<E> {
+                $name::new(self)
+            }
+        }
+
+        impl<E> $name<E> {
+            #[allow(missing_docs)]
+            pub fn new(value: $ty) -> Self {
                 $name {
-                    value: self,
+                    value: value,
                     marker: PhantomData,
                 }
             }
@@ -308,8 +322,15 @@ where
     type Deserializer = U32Deserializer<E>;
 
     fn into_deserializer(self) -> U32Deserializer<E> {
+        U32Deserializer::new(self)
+    }
+}
+
+impl<E> U32Deserializer<E> {
+    #[allow(missing_docs)]
+    pub fn new(value: u32) -> Self {
         U32Deserializer {
-            value: self,
+            value: value,
             marker: PhantomData,
         }
     }
@@ -390,8 +411,15 @@ where
     type Deserializer = StrDeserializer<'a, E>;
 
     fn into_deserializer(self) -> StrDeserializer<'a, E> {
+        StrDeserializer::new(self)
+    }
+}
+
+impl<'a, E> StrDeserializer<'a, E> {
+    #[allow(missing_docs)]
+    pub fn new(value: &'a str) -> Self {
         StrDeserializer {
-            value: self,
+            value: value,
             marker: PhantomData,
         }
     }
@@ -561,8 +589,16 @@ where
     type Deserializer = StringDeserializer<E>;
 
     fn into_deserializer(self) -> StringDeserializer<E> {
+        StringDeserializer::new(self)
+    }
+}
+
+#[cfg(any(feature = "std", feature = "alloc"))]
+impl<E> StringDeserializer<E> {
+    #[allow(missing_docs)]
+    pub fn new(value: String) -> Self {
         StringDeserializer {
-            value: self,
+            value: value,
             marker: PhantomData,
         }
     }
@@ -656,8 +692,16 @@ where
     type Deserializer = CowStrDeserializer<'a, E>;
 
     fn into_deserializer(self) -> CowStrDeserializer<'a, E> {
+        CowStrDeserializer::new(self)
+    }
+}
+
+#[cfg(any(feature = "std", feature = "alloc"))]
+impl<'a, E> CowStrDeserializer<'a, E> {
+    #[allow(missing_docs)]
+    pub fn new(value: Cow<'a, str>) -> Self {
         CowStrDeserializer {
-            value: self,
+            value: value,
             marker: PhantomData,
         }
     }
@@ -1457,7 +1501,7 @@ where
     where
         T: de::DeserializeSeed<'de>,
     {
-        match self.map.next_key_seed(seed)? {
+        match try!(self.map.next_key_seed(seed)) {
             Some(key) => Ok((key, private::map_as_enum(self.map))),
             None => Err(de::Error::invalid_type(de::Unexpected::Map, &"enum")),
         }
@@ -1466,6 +1510,41 @@ where
 
 ////////////////////////////////////////////////////////////////////////////////
 
+/// A deserializer holding an `EnumAccess`.
+#[derive(Clone, Debug)]
+pub struct EnumAccessDeserializer<A> {
+    access: A,
+}
+
+impl<A> EnumAccessDeserializer<A> {
+    /// Construct a new `EnumAccessDeserializer<A>`.
+    pub fn new(access: A) -> Self {
+        EnumAccessDeserializer { access: access }
+    }
+}
+
+impl<'de, A> de::Deserializer<'de> for EnumAccessDeserializer<A>
+where
+    A: de::EnumAccess<'de>,
+{
+    type Error = A::Error;
+
+    fn deserialize_any<V>(self, visitor: V) -> Result<V::Value, Self::Error>
+    where
+        V: de::Visitor<'de>,
+    {
+        visitor.visit_enum(self.access)
+    }
+
+    forward_to_deserialize_any! {
+        bool i8 i16 i32 i64 i128 u8 u16 u32 u64 u128 f32 f64 char str string
+        bytes byte_buf option unit unit_struct newtype_struct seq tuple
+        tuple_struct map struct enum identifier ignored_any
+    }
+}
+
+////////////////////////////////////////////////////////////////////////////////
+
 mod private {
     use lib::*;
 

serde/src/lib.rs

@@ -31,8 +31,7 @@
 //! for Serde by the community.
 //!
 //! - [JSON], the ubiquitous JavaScript Object Notation used by many HTTP APIs.
-//! - [Bincode], a compact binary format
+//! - [Postcard], a no\_std and embedded-systems friendly compact binary format.
-//!   used for IPC within the Servo rendering engine.
 //! - [CBOR], a Concise Binary Object Representation designed for small message
 //!   size without the need for version negotiation.
 //! - [YAML], a self-proclaimed human-friendly configuration language that ain't
@@ -45,7 +44,6 @@
 //! - [Avro], a binary format used within Apache Hadoop, with support for schema
 //!   definition.
 //! - [JSON5], a superset of JSON including some productions from ES5.
-//! - [Postcard], a no\_std and embedded-systems friendly compact binary format.
 //! - [URL] query strings, in the x-www-form-urlencoded format.
 //! - [Envy], a way to deserialize environment variables into Rust structs.
 //!   *(deserialization only)*
@@ -59,17 +57,16 @@
 //!   and from DynamoDB.
 //!
 //! [JSON]: https://github.com/serde-rs/json
-//! [Bincode]: https://github.com/bincode-org/bincode
+//! [Postcard]: https://github.com/jamesmunns/postcard
 //! [CBOR]: https://github.com/enarx/ciborium
 //! [YAML]: https://github.com/dtolnay/serde-yaml
 //! [MessagePack]: https://github.com/3Hren/msgpack-rust
-//! [TOML]: https://github.com/alexcrichton/toml-rs
+//! [TOML]: https://docs.rs/toml
 //! [Pickle]: https://github.com/birkenfeld/serde-pickle
 //! [RON]: https://github.com/ron-rs/ron
 //! [BSON]: https://github.com/mongodb/bson-rust
-//! [Avro]: https://github.com/flavray/avro-rs
+//! [Avro]: https://docs.rs/apache-avro
 //! [JSON5]: https://github.com/callum-oakley/json5-rs
-//! [Postcard]: https://github.com/jamesmunns/postcard
 //! [URL]: https://docs.rs/serde_qs
 //! [Envy]: https://github.com/softprops/envy
 //! [Envy Store]: https://github.com/softprops/envy-store
@@ -84,7 +81,7 @@
 ////////////////////////////////////////////////////////////////////////////////
 
 // Serde types in rustdoc of other crates get linked to here.
-#![doc(html_root_url = "https://docs.rs/serde/1.0.137")]
+#![doc(html_root_url = "https://docs.rs/serde/1.0.149")]
 // 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
@@ -120,8 +117,9 @@
         // correctly used
         derive_partial_eq_without_eq,
         enum_glob_use,
-        let_underscore_drop,
+        explicit_auto_deref,
         map_err_ignore,
+        new_without_default,
         result_unit_err,
         wildcard_imports,
         // not practical
@@ -250,6 +248,19 @@ mod lib {
     pub use self::core::time::Duration;
 }
 
+// None of this crate's error handling needs the `From::from` error conversion
+// performed implicitly by the `?` operator or the standard library's `try!`
+// macro. This simplified macro gives a 5.5% improvement in compile time
+// compared to standard `try!`, and 9% improvement compared to `?`.
+macro_rules! try {
+    ($expr:expr) => {
+        match $expr {
+            Ok(val) => val,
+            Err(err) => return Err(err),
+        }
+    };
+}
+
 ////////////////////////////////////////////////////////////////////////////////
 
 #[macro_use]

serde/src/private/de.rs

@@ -1262,6 +1262,17 @@ mod content {
         {
             match self.content {
                 Content::Unit => visitor.visit_unit(),
+
+                // Allow deserializing newtype variant containing unit.
+                //
+                //     #[derive(Deserialize)]
+                //     #[serde(tag = "result")]
+                //     enum Response<T> {
+                //         Success(T),
+                //     }
+                //
+                // We want {"result":"Success"} to deserialize into Response<()>.
+                Content::Map(ref v) if v.is_empty() => visitor.visit_unit(),
                 _ => Err(self.invalid_type(&visitor)),
             }
         }
@@ -1799,7 +1810,7 @@ mod content {
         V: Visitor<'de>,
         E: de::Error,
     {
-        let map = content.iter().map(|&(ref k, ref v)| {
+        let map = content.iter().map(|(k, v)| {
             (
                 ContentRefDeserializer::new(k),
                 ContentRefDeserializer::new(v),
@@ -2096,7 +2107,7 @@ mod content {
             let (variant, value) = match *self.content {
                 Content::Map(ref value) => {
                     let mut iter = value.iter();
-                    let &(ref variant, ref value) = match iter.next() {
+                    let (variant, value) = match iter.next() {
                         Some(v) => v,
                         None => {
                             return Err(de::Error::invalid_value(
@@ -2243,7 +2254,7 @@ mod content {
             V: de::Visitor<'de>,
         {
             match self.value {
-                Some(&Content::Seq(ref v)) => {
+                Some(Content::Seq(v)) => {
                     de::Deserializer::deserialize_any(SeqRefDeserializer::new(v), visitor)
                 }
                 Some(other) => Err(de::Error::invalid_type(
@@ -2266,10 +2277,10 @@ mod content {
             V: de::Visitor<'de>,
         {
             match self.value {
-                Some(&Content::Map(ref v)) => {
+                Some(Content::Map(v)) => {
                     de::Deserializer::deserialize_any(MapRefDeserializer::new(v), visitor)
                 }
-                Some(&Content::Seq(ref v)) => {
+                Some(Content::Seq(v)) => {
                     de::Deserializer::deserialize_any(SeqRefDeserializer::new(v), visitor)
                 }
                 Some(other) => Err(de::Error::invalid_type(
@@ -2392,7 +2403,7 @@ mod content {
             T: de::DeserializeSeed<'de>,
         {
             match self.iter.next() {
-                Some(&(ref key, ref value)) => {
+                Some((key, value)) => {
                     self.value = Some(value);
                     seed.deserialize(ContentRefDeserializer::new(key)).map(Some)
                 }

serde/src/private/ser.rs

@@ -51,7 +51,6 @@ enum Unsupported {
     String,
     ByteArray,
     Optional,
-    Unit,
     #[cfg(any(feature = "std", feature = "alloc"))]
     UnitStruct,
     Sequence,
@@ -70,7 +69,6 @@ impl Display for Unsupported {
             Unsupported::String => formatter.write_str("a string"),
             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"),
@@ -184,7 +182,9 @@ where
     }
 
     fn serialize_unit(self) -> Result<Self::Ok, Self::Error> {
-        Err(self.bad_type(Unsupported::Unit))
+        let mut map = try!(self.delegate.serialize_map(Some(1)));
+        try!(map.serialize_entry(self.tag, self.variant_name));
+        map.end()
     }
 
     fn serialize_unit_struct(self, _: &'static str) -> Result<Self::Ok, Self::Error> {
@@ -525,7 +525,7 @@ mod content {
                 Content::Map(ref entries) => {
                     use ser::SerializeMap;
                     let mut map = try!(serializer.serialize_map(Some(entries.len())));
-                    for &(ref k, ref v) in entries {
+                    for (k, v) in entries {
                         try!(map.serialize_entry(k, v));
                     }
                     map.end()

serde/src/ser/impls.rs

@@ -182,7 +182,25 @@ where
     }
 }
 
-#[cfg(any(feature = "std", feature = "alloc"))]
+#[cfg(all(any(feature = "std", feature = "alloc"), not(no_relaxed_trait_bounds)))]
+macro_rules! seq_impl {
+    ($ty:ident < T $(: $tbound1:ident $(+ $tbound2:ident)*)* $(, $typaram:ident : $bound:ident)* >) => {
+        impl<T $(, $typaram)*> Serialize for $ty<T $(, $typaram)*>
+        where
+            T: Serialize,
+        {
+            #[inline]
+            fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
+            where
+                S: Serializer,
+            {
+                serializer.collect_seq(self)
+            }
+        }
+    }
+}
+
+#[cfg(all(any(feature = "std", feature = "alloc"), no_relaxed_trait_bounds))]
 macro_rules! seq_impl {
     ($ty:ident < T $(: $tbound1:ident $(+ $tbound2:ident)*)* $(, $typaram:ident : $bound:ident)* >) => {
         impl<T $(, $typaram)*> Serialize for $ty<T $(, $typaram)*>
@@ -522,7 +540,7 @@ where
     }
 }
 
-impl<T> Serialize for RefCell<T>
+impl<T: ?Sized> Serialize for RefCell<T>
 where
     T: Serialize,
 {
@@ -538,7 +556,7 @@ where
 }
 
 #[cfg(feature = "std")]
-impl<T> Serialize for Mutex<T>
+impl<T: ?Sized> Serialize for Mutex<T>
 where
     T: Serialize,
 {
@@ -554,7 +572,7 @@ where
 }
 
 #[cfg(feature = "std")]
-impl<T> Serialize for RwLock<T>
+impl<T: ?Sized> Serialize for RwLock<T>
 where
     T: Serialize,
 {
@@ -614,9 +632,10 @@ impl Serialize for SystemTime {
         S: Serializer,
     {
         use super::SerializeStruct;
-        let duration_since_epoch = self
+        let duration_since_epoch = match self.duration_since(UNIX_EPOCH) {
-            .duration_since(UNIX_EPOCH)
+            Ok(duration_since_epoch) => duration_since_epoch,
-            .map_err(|_| S::Error::custom("SystemTime must be later than UNIX_EPOCH"))?;
+            Err(_) => return Err(S::Error::custom("SystemTime must be later than UNIX_EPOCH")),
+        };
         let mut state = try!(serializer.serialize_struct("SystemTime", 2));
         try!(state.serialize_field("secs_since_epoch", &duration_since_epoch.as_secs()));
         try!(state.serialize_field("nanos_since_epoch", &duration_since_epoch.subsec_nanos()));
@@ -735,8 +754,9 @@ impl Serialize for net::Ipv4Addr {
                 // Skip over delimiters that we initialized buf with
                 written += format_u8(*oct, &mut buf[written + 1..]) + 1;
             }
-            // We've only written ASCII bytes to the buffer, so it is valid UTF-8
+            // Safety: We've only written ASCII bytes to the buffer, so it is valid UTF-8
-            serializer.serialize_str(unsafe { str::from_utf8_unchecked(&buf[..written]) })
+            let buf = unsafe { str::from_utf8_unchecked(&buf[..written]) };
+            serializer.serialize_str(buf)
         } else {
             self.octets().serialize(serializer)
         }
@@ -916,7 +936,7 @@ macro_rules! atomic_impl {
                     S: Serializer,
                 {
                     // Matches the atomic ordering used in libcore for the Debug impl
-                    self.load(Ordering::SeqCst).serialize(serializer)
+                    self.load(Ordering::Relaxed).serialize(serializer)
                 }
             }
         )*

serde/src/ser/mod.rs

@@ -30,7 +30,7 @@
 //! # The Serializer trait
 //!
 //! [`Serializer`] implementations are provided by third-party crates, for
-//! example [`serde_json`], [`serde_yaml`] and [`bincode`].
+//! example [`serde_json`], [`serde_yaml`] and [`postcard`].
 //!
 //! A partial list of well-maintained formats is given on the [Serde
 //! website][data formats].
@@ -99,7 +99,7 @@
 //! [`LinkedHashMap<K, V>`]: https://docs.rs/linked-hash-map/*/linked_hash_map/struct.LinkedHashMap.html
 //! [`Serialize`]: ../trait.Serialize.html
 //! [`Serializer`]: ../trait.Serializer.html
-//! [`bincode`]: https://github.com/bincode-org/bincode
+//! [`postcard`]: https://github.com/jamesmunns/postcard
 //! [`linked-hash-map`]: https://crates.io/crates/linked-hash-map
 //! [`serde_derive`]: https://crates.io/crates/serde_derive
 //! [`serde_json`]: https://github.com/serde-rs/json
@@ -314,7 +314,7 @@ pub trait Serialize {
 ///    - For example the `E::S` in `enum E { S { r: u8, g: u8, b: u8 } }`.
 ///
 /// Many Serde serializers produce text or binary data as output, for example
-/// JSON or Bincode. This is not a requirement of the `Serializer` trait, and
+/// JSON or Postcard. This is not a requirement of the `Serializer` trait, and
 /// there are serializers that do not produce text or binary output. One example
 /// is the `serde_json::value::Serializer` (distinct from the main `serde_json`
 /// serializer) that produces a `serde_json::Value` data structure in memory as
@@ -1423,7 +1423,7 @@ pub trait Serializer: Sized {
     /// Some types have a human-readable form that may be somewhat expensive to
     /// construct, as well as a binary form that is compact and efficient.
     /// Generally text-based formats like JSON and YAML will prefer to use the
-    /// human-readable one and binary formats like Bincode will prefer the
+    /// human-readable one and binary formats like Postcard will prefer the
     /// compact one.
     ///
     /// ```edition2018

serde_derive/Cargo.toml

@@ -1,16 +1,17 @@
 [package]
 name = "serde_derive"
-version = "1.0.137" # remember to update html_root_url
+version = "1.0.149" # remember to update html_root_url
 authors = ["Erick Tryzelaar <erick.tryzelaar@gmail.com>", "David Tolnay <dtolnay@gmail.com>"]
-rust-version = "1.31"
+categories = ["no-std"]
-license = "MIT OR Apache-2.0"
 description = "Macros 1.1 implementation of #[derive(Serialize, Deserialize)]"
-homepage = "https://serde.rs"
-repository = "https://github.com/serde-rs/serde"
 documentation = "https://serde.rs/derive.html"
-keywords = ["serde", "serialization", "no_std"]
+homepage = "https://serde.rs"
-readme = "crates-io.md"
 include = ["build.rs", "src/**/*.rs", "crates-io.md", "README.md", "LICENSE-APACHE", "LICENSE-MIT"]
+keywords = ["serde", "serialization", "no_std", "derive"]
+license = "MIT OR Apache-2.0"
+readme = "crates-io.md"
+repository = "https://github.com/serde-rs/serde"
+rust-version = "1.31"
 
 [features]
 default = []
@@ -23,7 +24,7 @@ proc-macro = true
 [dependencies]
 proc-macro2 = "1.0"
 quote = "1.0"
-syn = "1.0.90"
+syn = "1.0.104"
 
 [dev-dependencies]
 serde = { version = "1.0", path = "../serde" }

serde_derive/build.rs

@@ -13,14 +13,14 @@ fn main() {
 
     // Underscore const names stabilized in Rust 1.37:
     // https://blog.rust-lang.org/2019/08/15/Rust-1.37.0.html#using-unnamed-const-items-for-macros
-    if minor >= 37 {
+    if minor < 37 {
-        println!("cargo:rustc-cfg=underscore_consts");
+        println!("cargo:rustc-cfg=no_underscore_consts");
     }
 
     // The ptr::addr_of! macro stabilized in Rust 1.51:
     // https://blog.rust-lang.org/2021/03/25/Rust-1.51.0.html#stabilized-apis
-    if minor >= 51 {
+    if minor < 51 {
-        println!("cargo:rustc-cfg=ptr_addr_of");
+        println!("cargo:rustc-cfg=no_ptr_addr_of");
     }
 }
 

serde_derive/src/de.rs

@@ -10,6 +10,7 @@ use fragment::{Expr, Fragment, Match, Stmts};
 use internals::ast::{Container, Data, Field, Style, Variant};
 use internals::{attr, replace_receiver, ungroup, Ctxt, Derive};
 use pretend;
+use this;
 
 use std::collections::BTreeSet;
 use std::ptr;
@@ -111,9 +112,13 @@ struct Parameters {
     local: syn::Ident,
 
     /// Path to the type the impl is for. Either a single `Ident` for local
-    /// types or `some::remote::Ident` for remote types. Does not include
+    /// types (does not include generic parameters) or `some::remote::Path` for
-    /// generic parameters.
+    /// remote types.
-    this: syn::Path,
+    this_type: syn::Path,
+
+    /// Same as `this_type` but using `::<T>` for generic parameters for use in
+    /// expression position.
+    this_value: syn::Path,
 
     /// Generics including any explicit and inferred bounds for the impl.
     generics: syn::Generics,
@@ -133,10 +138,8 @@ struct Parameters {
 impl Parameters {
     fn new(cont: &Container) -> Self {
         let local = cont.ident.clone();
-        let this = match cont.attrs.remote() {
+        let this_type = this::this_type(cont);
-            Some(remote) => remote.clone(),
+        let this_value = this::this_value(cont);
-            None => cont.ident.clone().into(),
-        };
         let borrowed = borrowed_lifetimes(cont);
         let generics = build_generics(cont, &borrowed);
         let has_getter = cont.data.has_getter();
@@ -144,7 +147,8 @@ impl Parameters {
 
         Parameters {
             local,
-            this,
+            this_type,
+            this_value,
             generics,
             borrowed,
             has_getter,
@@ -155,7 +159,7 @@ impl Parameters {
     /// Type name to use in error messages and `&'static str` arguments to
     /// various Deserializer methods.
     fn type_name(&self) -> String {
-        self.this.segments.last().unwrap().ident.to_string()
+        self.this_type.segments.last().unwrap().ident.to_string()
     }
 }
 
@@ -358,7 +362,7 @@ fn deserialize_transparent(cont: &Container, params: &Parameters) -> Fragment {
         Data::Enum(_) => unreachable!(),
     };
 
-    let this = &params.this;
+    let this_value = &params.this_value;
     let transparent_field = fields.iter().find(|f| f.attrs.transparent()).unwrap();
 
     let path = match transparent_field.attrs.deserialize_with() {
@@ -386,7 +390,7 @@ fn deserialize_transparent(cont: &Container, params: &Parameters) -> Fragment {
     quote_block! {
         _serde::__private::Result::map(
             #path(__deserializer),
-            |__transparent| #this { #(#assign),* })
+            |__transparent| #this_value { #(#assign),* })
     }
 }
 
@@ -407,7 +411,8 @@ fn deserialize_try_from(type_try_from: &syn::Type) -> Fragment {
 }
 
 fn deserialize_unit_struct(params: &Parameters, cattrs: &attr::Container) -> Fragment {
-    let this = &params.this;
+    let this_type = &params.this_type;
+    let this_value = &params.this_value;
     let type_name = cattrs.name().deserialize_name();
 
     let expecting = format!("unit struct {}", params.type_name());
@@ -417,7 +422,7 @@ fn deserialize_unit_struct(params: &Parameters, cattrs: &attr::Container) -> Fra
         struct __Visitor;
 
         impl<'de> _serde::de::Visitor<'de> for __Visitor {
-            type Value = #this;
+            type Value = #this_type;
 
             fn expecting(&self, __formatter: &mut _serde::__private::Formatter) -> _serde::__private::fmt::Result {
                 _serde::__private::Formatter::write_str(__formatter, #expecting)
@@ -428,7 +433,7 @@ fn deserialize_unit_struct(params: &Parameters, cattrs: &attr::Container) -> Fra
             where
                 __E: _serde::de::Error,
             {
-                _serde::__private::Ok(#this)
+                _serde::__private::Ok(#this_value)
             }
         }
 
@@ -443,7 +448,8 @@ fn deserialize_tuple(
     cattrs: &attr::Container,
     deserializer: Option<TokenStream>,
 ) -> Fragment {
-    let this = &params.this;
+    let this_type = &params.this_type;
+    let this_value = &params.this_value;
     let (de_impl_generics, de_ty_generics, ty_generics, where_clause) =
         split_with_de_lifetime(params);
     let delife = params.borrowed.de_lifetime();
@@ -457,7 +463,7 @@ fn deserialize_tuple(
         let local = &params.local;
         quote!(#local)
     } else {
-        quote!(#this)
+        quote!(#this_value)
     };
 
     let is_enum = variant_ident.is_some();
@@ -485,7 +491,7 @@ fn deserialize_tuple(
 
     let visitor_expr = quote! {
         __Visitor {
-            marker: _serde::__private::PhantomData::<#this #ty_generics>,
+            marker: _serde::__private::PhantomData::<#this_type #ty_generics>,
             lifetime: _serde::__private::PhantomData,
         }
     };
@@ -510,12 +516,12 @@ fn deserialize_tuple(
 
     quote_block! {
         struct __Visitor #de_impl_generics #where_clause {
-            marker: _serde::__private::PhantomData<#this #ty_generics>,
+            marker: _serde::__private::PhantomData<#this_type #ty_generics>,
             lifetime: _serde::__private::PhantomData<&#delife ()>,
         }
 
         impl #de_impl_generics _serde::de::Visitor<#delife> for __Visitor #de_ty_generics #where_clause {
-            type Value = #this #ty_generics;
+            type Value = #this_type #ty_generics;
 
             fn expecting(&self, __formatter: &mut _serde::__private::Formatter) -> _serde::__private::fmt::Result {
                 _serde::__private::Formatter::write_str(__formatter, #expecting)
@@ -544,7 +550,7 @@ fn deserialize_tuple_in_place(
     cattrs: &attr::Container,
     deserializer: Option<TokenStream>,
 ) -> Fragment {
-    let this = &params.this;
+    let this_type = &params.this_type;
     let (de_impl_generics, de_ty_generics, ty_generics, where_clause) =
         split_with_de_lifetime(params);
     let delife = params.borrowed.de_lifetime();
@@ -600,7 +606,7 @@ fn deserialize_tuple_in_place(
 
     quote_block! {
         struct __Visitor #in_place_impl_generics #where_clause {
-            place: &#place_life mut #this #ty_generics,
+            place: &#place_life mut #this_type #ty_generics,
             lifetime: _serde::__private::PhantomData<&#delife ()>,
         }
 
@@ -705,9 +711,10 @@ fn deserialize_seq(
     };
 
     if params.has_getter {
-        let this = &params.this;
+        let this_type = &params.this_type;
+        let (_, ty_generics, _) = params.generics.split_for_impl();
         result = quote! {
-            _serde::__private::Into::<#this>::into(#result)
+            _serde::__private::Into::<#this_type #ty_generics>::into(#result)
         };
     }
 
@@ -801,14 +808,14 @@ fn deserialize_seq_in_place(
         }
     });
 
-    let this = &params.this;
+    let this_type = &params.this_type;
     let (_, ty_generics, _) = params.generics.split_for_impl();
     let let_default = match cattrs.default() {
         attr::Default::Default => Some(quote!(
-            let __default: #this #ty_generics  = _serde::__private::Default::default();
+            let __default: #this_type #ty_generics = _serde::__private::Default::default();
         )),
         attr::Default::Path(path) => Some(quote!(
-            let __default: #this #ty_generics  = #path();
+            let __default: #this_type #ty_generics = #path();
         )),
         attr::Default::None => {
             // We don't need the default value, to prevent an unused variable warning
@@ -849,9 +856,10 @@ fn deserialize_newtype_struct(
 
     let mut result = quote!(#type_path(__field0));
     if params.has_getter {
-        let this = &params.this;
+        let this_type = &params.this_type;
+        let (_, ty_generics, _) = params.generics.split_for_impl();
         result = quote! {
-            _serde::__private::Into::<#this>::into(#result)
+            _serde::__private::Into::<#this_type #ty_generics>::into(#result)
         };
     }
 
@@ -901,7 +909,8 @@ fn deserialize_struct(
 ) -> Fragment {
     let is_enum = variant_ident.is_some();
 
-    let this = &params.this;
+    let this_type = &params.this_type;
+    let this_value = &params.this_value;
     let (de_impl_generics, de_ty_generics, ty_generics, where_clause) =
         split_with_de_lifetime(params);
     let delife = params.borrowed.de_lifetime();
@@ -913,7 +922,7 @@ fn deserialize_struct(
         let local = &params.local;
         quote!(#local)
     } else {
-        quote!(#this)
+        quote!(#this_value)
     };
 
     let type_path = match variant_ident {
@@ -941,7 +950,7 @@ fn deserialize_struct(
 
     let visitor_expr = quote! {
         __Visitor {
-            marker: _serde::__private::PhantomData::<#this #ty_generics>,
+            marker: _serde::__private::PhantomData::<#this_type #ty_generics>,
             lifetime: _serde::__private::PhantomData,
         }
     };
@@ -993,7 +1002,7 @@ fn deserialize_struct(
     let visitor_seed = if is_enum && cattrs.has_flatten() {
         Some(quote! {
             impl #de_impl_generics _serde::de::DeserializeSeed<#delife> for __Visitor #de_ty_generics #where_clause {
-                type Value = #this #ty_generics;
+                type Value = #this_type #ty_generics;
 
                 fn deserialize<__D>(self, __deserializer: __D) -> _serde::__private::Result<Self::Value, __D::Error>
                 where
@@ -1011,12 +1020,12 @@ fn deserialize_struct(
         #field_visitor
 
         struct __Visitor #de_impl_generics #where_clause {
-            marker: _serde::__private::PhantomData<#this #ty_generics>,
+            marker: _serde::__private::PhantomData<#this_type #ty_generics>,
             lifetime: _serde::__private::PhantomData<&#delife ()>,
         }
 
         impl #de_impl_generics _serde::de::Visitor<#delife> for __Visitor #de_ty_generics #where_clause {
-            type Value = #this #ty_generics;
+            type Value = #this_type #ty_generics;
 
             fn expecting(&self, __formatter: &mut _serde::__private::Formatter) -> _serde::__private::fmt::Result {
                 _serde::__private::Formatter::write_str(__formatter, #expecting)
@@ -1057,7 +1066,7 @@ fn deserialize_struct_in_place(
         return None;
     }
 
-    let this = &params.this;
+    let this_type = &params.this_type;
     let (de_impl_generics, de_ty_generics, ty_generics, where_clause) =
         split_with_de_lifetime(params);
     let delife = params.borrowed.de_lifetime();
@@ -1123,7 +1132,7 @@ fn deserialize_struct_in_place(
         #field_visitor
 
         struct __Visitor #in_place_impl_generics #where_clause {
-            place: &#place_life mut #this #ty_generics,
+            place: &#place_life mut #this_type #ty_generics,
             lifetime: _serde::__private::PhantomData<&#delife ()>,
         }
 
@@ -1212,7 +1221,7 @@ fn deserialize_externally_tagged_enum(
     variants: &[Variant],
     cattrs: &attr::Container,
 ) -> Fragment {
-    let this = &params.this;
+    let this_type = &params.this_type;
     let (de_impl_generics, de_ty_generics, ty_generics, where_clause) =
         split_with_de_lifetime(params);
     let delife = params.borrowed.de_lifetime();
@@ -1266,12 +1275,12 @@ fn deserialize_externally_tagged_enum(
         #variant_visitor
 
         struct __Visitor #de_impl_generics #where_clause {
-            marker: _serde::__private::PhantomData<#this #ty_generics>,
+            marker: _serde::__private::PhantomData<#this_type #ty_generics>,
             lifetime: _serde::__private::PhantomData<&#delife ()>,
         }
 
         impl #de_impl_generics _serde::de::Visitor<#delife> for __Visitor #de_ty_generics #where_clause {
-            type Value = #this #ty_generics;
+            type Value = #this_type #ty_generics;
 
             fn expecting(&self, __formatter: &mut _serde::__private::Formatter) -> _serde::__private::fmt::Result {
                 _serde::__private::Formatter::write_str(__formatter, #expecting)
@@ -1292,7 +1301,7 @@ fn deserialize_externally_tagged_enum(
             #type_name,
             VARIANTS,
             __Visitor {
-                marker: _serde::__private::PhantomData::<#this #ty_generics>,
+                marker: _serde::__private::PhantomData::<#this_type #ty_generics>,
                 lifetime: _serde::__private::PhantomData,
             },
         )
@@ -1354,7 +1363,8 @@ fn deserialize_adjacently_tagged_enum(
     tag: &str,
     content: &str,
 ) -> Fragment {
-    let this = &params.this;
+    let this_type = &params.this_type;
+    let this_value = &params.this_value;
     let (de_impl_generics, de_ty_generics, ty_generics, where_clause) =
         split_with_de_lifetime(params);
     let delife = params.borrowed.de_lifetime();
@@ -1415,13 +1425,13 @@ fn deserialize_adjacently_tagged_enum(
 
             let arm = match variant.style {
                 Style::Unit => quote! {
-                    _serde::__private::Ok(#this::#variant_ident)
+                    _serde::__private::Ok(#this_value::#variant_ident)
                 },
                 Style::Newtype if variant.attrs.deserialize_with().is_none() => {
                     let span = variant.original.span();
                     let func = quote_spanned!(span=> _serde::__private::de::missing_field);
                     quote! {
-                        #func(#content).map(#this::#variant_ident)
+                        #func(#content).map(#this_value::#variant_ident)
                     }
                 }
                 _ => {
@@ -1513,12 +1523,12 @@ fn deserialize_adjacently_tagged_enum(
 
         struct __Seed #de_impl_generics #where_clause {
             field: __Field,
-            marker: _serde::__private::PhantomData<#this #ty_generics>,
+            marker: _serde::__private::PhantomData<#this_type #ty_generics>,
             lifetime: _serde::__private::PhantomData<&#delife ()>,
         }
 
         impl #de_impl_generics _serde::de::DeserializeSeed<#delife> for __Seed #de_ty_generics #where_clause {
-            type Value = #this #ty_generics;
+            type Value = #this_type #ty_generics;
 
             fn deserialize<__D>(self, __deserializer: __D) -> _serde::__private::Result<Self::Value, __D::Error>
             where
@@ -1531,12 +1541,12 @@ fn deserialize_adjacently_tagged_enum(
         }
 
         struct __Visitor #de_impl_generics #where_clause {
-            marker: _serde::__private::PhantomData<#this #ty_generics>,
+            marker: _serde::__private::PhantomData<#this_type #ty_generics>,
             lifetime: _serde::__private::PhantomData<&#delife ()>,
         }
 
         impl #de_impl_generics _serde::de::Visitor<#delife> for __Visitor #de_ty_generics #where_clause {
-            type Value = #this #ty_generics;
+            type Value = #this_type #ty_generics;
 
             fn expecting(&self, __formatter: &mut _serde::__private::Formatter) -> _serde::__private::fmt::Result {
                 _serde::__private::Formatter::write_str(__formatter, #expecting)
@@ -1638,7 +1648,7 @@ fn deserialize_adjacently_tagged_enum(
             #type_name,
             FIELDS,
             __Visitor {
-                marker: _serde::__private::PhantomData::<#this #ty_generics>,
+                marker: _serde::__private::PhantomData::<#this_type #ty_generics>,
                 lifetime: _serde::__private::PhantomData,
             },
         )
@@ -1707,10 +1717,10 @@ fn deserialize_externally_tagged_variant(
 
     match variant.style {
         Style::Unit => {
-            let this = &params.this;
+            let this_value = &params.this_value;
             quote_block! {
                 try!(_serde::de::VariantAccess::unit_variant(__variant));
-                _serde::__private::Ok(#this::#variant_ident)
+                _serde::__private::Ok(#this_value::#variant_ident)
             }
         }
         Style::Newtype => deserialize_externally_tagged_newtype_variant(
@@ -1749,7 +1759,7 @@ fn deserialize_internally_tagged_variant(
 
     match effective_style(variant) {
         Style::Unit => {
-            let this = &params.this;
+            let this_value = &params.this_value;
             let type_name = params.type_name();
             let variant_name = variant.ident.to_string();
             let default = variant.fields.get(0).map(|field| {
@@ -1758,7 +1768,7 @@ fn deserialize_internally_tagged_variant(
             });
             quote_block! {
                 try!(_serde::Deserializer::deserialize_any(#deserializer, _serde::__private::de::InternallyTaggedUnitVisitor::new(#type_name, #variant_name)));
-                _serde::__private::Ok(#this::#variant_ident #default)
+                _serde::__private::Ok(#this_value::#variant_ident #default)
             }
         }
         Style::Newtype => deserialize_untagged_newtype_variant(
@@ -1796,7 +1806,7 @@ fn deserialize_untagged_variant(
 
     match effective_style(variant) {
         Style::Unit => {
-            let this = &params.this;
+            let this_value = &params.this_value;
             let type_name = params.type_name();
             let variant_name = variant.ident.to_string();
             let default = variant.fields.get(0).map(|field| {
@@ -1808,7 +1818,7 @@ fn deserialize_untagged_variant(
                     #deserializer,
                     _serde::__private::de::UntaggedUnitVisitor::new(#type_name, #variant_name)
                 ) {
-                    _serde::__private::Ok(()) => _serde::__private::Ok(#this::#variant_ident #default),
+                    _serde::__private::Ok(()) => _serde::__private::Ok(#this_value::#variant_ident #default),
                     _serde::__private::Err(__err) => _serde::__private::Err(__err),
                 }
             }
@@ -1843,14 +1853,13 @@ fn deserialize_externally_tagged_newtype_variant(
     field: &Field,
     cattrs: &attr::Container,
 ) -> Fragment {
-    let this = &params.this;
+    let this_value = &params.this_value;
 
     if field.attrs.skip_deserializing() {
-        let this = &params.this;
         let default = Expr(expr_is_missing(field, cattrs));
         return quote_block! {
             try!(_serde::de::VariantAccess::unit_variant(__variant));
-            _serde::__private::Ok(#this::#variant_ident(#default))
+            _serde::__private::Ok(#this_value::#variant_ident(#default))
         };
     }
 
@@ -1861,7 +1870,7 @@ fn deserialize_externally_tagged_newtype_variant(
             let func =
                 quote_spanned!(span=> _serde::de::VariantAccess::newtype_variant::<#field_ty>);
             quote_expr! {
-                _serde::__private::Result::map(#func(__variant), #this::#variant_ident)
+                _serde::__private::Result::map(#func(__variant), #this_value::#variant_ident)
             }
         }
         Some(path) => {
@@ -1870,7 +1879,7 @@ fn deserialize_externally_tagged_newtype_variant(
                 #wrapper
                 _serde::__private::Result::map(
                     _serde::de::VariantAccess::newtype_variant::<#wrapper_ty>(__variant),
-                    |__wrapper| #this::#variant_ident(__wrapper.value))
+                    |__wrapper| #this_value::#variant_ident(__wrapper.value))
             }
         }
     }
@@ -1882,20 +1891,20 @@ fn deserialize_untagged_newtype_variant(
     field: &Field,
     deserializer: &TokenStream,
 ) -> Fragment {
-    let this = &params.this;
+    let this_value = &params.this_value;
     let field_ty = field.ty;
     match field.attrs.deserialize_with() {
         None => {
             let span = field.original.span();
             let func = quote_spanned!(span=> <#field_ty as _serde::Deserialize>::deserialize);
             quote_expr! {
-                _serde::__private::Result::map(#func(#deserializer), #this::#variant_ident)
+                _serde::__private::Result::map(#func(#deserializer), #this_value::#variant_ident)
             }
         }
         Some(path) => {
             quote_block! {
                 let __value: _serde::__private::Result<#field_ty, _> = #path(#deserializer);
-                _serde::__private::Result::map(__value, #this::#variant_ident)
+                _serde::__private::Result::map(__value, #this_value::#variant_ident)
             }
         }
     }
@@ -1907,7 +1916,7 @@ fn deserialize_generated_identifier(
     is_variant: bool,
     other_idx: Option<usize>,
 ) -> Fragment {
-    let this = quote!(__Field);
+    let this_value = quote!(__Field);
     let field_idents: &Vec<_> = &fields.iter().map(|(_, ident, _)| ident).collect();
 
     let (ignore_variant, fallthrough) = if !is_variant && cattrs.has_flatten() {
@@ -1927,7 +1936,7 @@ fn deserialize_generated_identifier(
     };
 
     let visitor_impl = Stmts(deserialize_identifier(
-        &this,
+        &this_value,
         fields,
         is_variant,
         fallthrough,
@@ -1982,8 +1991,8 @@ fn deserialize_custom_identifier(
         attr::Identifier::No => unreachable!(),
     };
 
-    let this = &params.this;
+    let this_type = params.this_type.to_token_stream();
-    let this = quote!(#this);
+    let this_value = params.this_value.to_token_stream();
 
     let (ordinary, fallthrough, fallthrough_borrowed) = if let Some(last) = variants.last() {
         let last_ident = &last.ident;
@@ -1992,7 +2001,7 @@ fn deserialize_custom_identifier(
             // last variant (checked in `check_identifier`), so all preceding
             // are ordinary variants.
             let ordinary = &variants[..variants.len() - 1];
-            let fallthrough = quote!(_serde::__private::Ok(#this::#last_ident));
+            let fallthrough = quote!(_serde::__private::Ok(#this_value::#last_ident));
             (ordinary, Some(fallthrough), None)
         } else if let Style::Newtype = last.style {
             let ordinary = &variants[..variants.len() - 1];
@@ -2002,7 +2011,7 @@ fn deserialize_custom_identifier(
                         _serde::Deserialize::deserialize(
                             _serde::__private::de::IdentifierDeserializer::from(#value)
                         ),
-                        #this::#last_ident)
+                        #this_value::#last_ident)
                 }
             };
             (
@@ -2050,7 +2059,7 @@ fn deserialize_custom_identifier(
         split_with_de_lifetime(params);
     let delife = params.borrowed.de_lifetime();
     let visitor_impl = Stmts(deserialize_identifier(
-        &this,
+        &this_value,
         &names_idents,
         is_variant,
         fallthrough,
@@ -2063,18 +2072,18 @@ fn deserialize_custom_identifier(
         #names_const
 
         struct __FieldVisitor #de_impl_generics #where_clause {
-            marker: _serde::__private::PhantomData<#this #ty_generics>,
+            marker: _serde::__private::PhantomData<#this_type #ty_generics>,
             lifetime: _serde::__private::PhantomData<&#delife ()>,
         }
 
         impl #de_impl_generics _serde::de::Visitor<#delife> for __FieldVisitor #de_ty_generics #where_clause {
-            type Value = #this #ty_generics;
+            type Value = #this_type #ty_generics;
 
             #visitor_impl
         }
 
         let __visitor = __FieldVisitor {
-            marker: _serde::__private::PhantomData::<#this #ty_generics>,
+            marker: _serde::__private::PhantomData::<#this_type #ty_generics>,
             lifetime: _serde::__private::PhantomData,
         };
         _serde::Deserializer::deserialize_identifier(__deserializer, __visitor)
@@ -2082,7 +2091,7 @@ fn deserialize_custom_identifier(
 }
 
 fn deserialize_identifier(
-    this: &TokenStream,
+    this_value: &TokenStream,
     fields: &[(String, Ident, Vec<String>)],
     is_variant: bool,
     fallthrough: Option<TokenStream>,
@@ -2103,11 +2112,11 @@ fn deserialize_identifier(
 
     let constructors: &Vec<_> = &flat_fields
         .iter()
-        .map(|(_, ident)| quote!(#this::#ident))
+        .map(|(_, ident)| quote!(#this_value::#ident))
         .collect();
     let main_constructors: &Vec<_> = &fields
         .iter()
-        .map(|(_, ident, _)| quote!(#this::#ident))
+        .map(|(_, ident, _)| quote!(#this_value::#ident))
         .collect();
 
     let expecting = expecting.unwrap_or(if is_variant {
@@ -2621,9 +2630,10 @@ fn deserialize_map(
 
     let mut result = quote!(#struct_path { #(#result),* });
     if params.has_getter {
-        let this = &params.this;
+        let this_type = &params.this_type;
+        let (_, ty_generics, _) = params.generics.split_for_impl();
         result = quote! {
-            _serde::__private::Into::<#this>::into(#result)
+            _serde::__private::Into::<#this_type #ty_generics>::into(#result)
         };
     }
 
@@ -2803,15 +2813,15 @@ fn deserialize_map_in_place(
             }
         });
 
-    let this = &params.this;
+    let this_type = &params.this_type;
     let (_, _, ty_generics, _) = split_with_de_lifetime(params);
 
     let let_default = match cattrs.default() {
         attr::Default::Default => Some(quote!(
-            let __default: #this #ty_generics = _serde::__private::Default::default();
+            let __default: #this_type #ty_generics = _serde::__private::Default::default();
         )),
         attr::Default::Path(path) => Some(quote!(
-            let __default: #this #ty_generics = #path();
+            let __default: #this_type #ty_generics = #path();
         )),
         attr::Default::None => {
             // We don't need the default value, to prevent an unused variable warning
@@ -2844,7 +2854,7 @@ fn wrap_deserialize_with(
     value_ty: &TokenStream,
     deserialize_with: &syn::ExprPath,
 ) -> (TokenStream, TokenStream) {
-    let this = &params.this;
+    let this_type = &params.this_type;
     let (de_impl_generics, de_ty_generics, ty_generics, where_clause) =
         split_with_de_lifetime(params);
     let delife = params.borrowed.de_lifetime();
@@ -2852,7 +2862,7 @@ fn wrap_deserialize_with(
     let wrapper = quote! {
         struct __DeserializeWith #de_impl_generics #where_clause {
             value: #value_ty,
-            phantom: _serde::__private::PhantomData<#this #ty_generics>,
+            phantom: _serde::__private::PhantomData<#this_type #ty_generics>,
             lifetime: _serde::__private::PhantomData<&#delife ()>,
         }
 
@@ -2903,7 +2913,7 @@ fn unwrap_to_variant_closure(
     variant: &Variant,
     with_wrapper: bool,
 ) -> TokenStream {
-    let this = &params.this;
+    let this_value = &params.this_value;
     let variant_ident = &variant.ident;
 
     let (arg, wrapper) = if with_wrapper {
@@ -2924,23 +2934,23 @@ fn unwrap_to_variant_closure(
         Style::Struct if variant.fields.len() == 1 => {
             let member = &variant.fields[0].member;
             quote! {
-                |#arg| #this::#variant_ident { #member: #wrapper }
+                |#arg| #this_value::#variant_ident { #member: #wrapper }
             }
         }
         Style::Struct => {
             let members = variant.fields.iter().map(|field| &field.member);
             quote! {
-                |#arg| #this::#variant_ident { #(#members: #wrapper.#field_access),* }
+                |#arg| #this_value::#variant_ident { #(#members: #wrapper.#field_access),* }
             }
         }
         Style::Tuple => quote! {
-            |#arg| #this::#variant_ident(#(#wrapper.#field_access),*)
+            |#arg| #this_value::#variant_ident(#(#wrapper.#field_access),*)
         },
         Style::Newtype => quote! {
-            |#arg| #this::#variant_ident(#wrapper)
+            |#arg| #this_value::#variant_ident(#wrapper)
         },
         Style::Unit => quote! {
-            |#arg| #this::#variant_ident
+            |#arg| #this_value::#variant_ident
         },
     }
 }

serde_derive/src/dummy.rs

@@ -12,10 +12,10 @@ pub fn wrap_in_const(
 ) -> TokenStream {
     let try_replacement = try::replacement();
 
-    let dummy_const = if cfg!(underscore_consts) {
+    let dummy_const = if cfg!(no_underscore_consts) {
-        format_ident!("_")
-    } else {
         format_ident!("_IMPL_{}_FOR_{}", trait_, unraw(ty))
+    } else {
+        format_ident!("_")
     };
 
     let use_serde = match serde_path {

serde_derive/src/internals/check.rs

@@ -6,6 +6,7 @@ use syn::{Member, Type};
 /// 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: &mut Container, derive: Derive) {
+    check_remote_generic(cx, cont);
     check_getter(cx, cont);
     check_flatten(cx, cont);
     check_identifier(cx, cont);
@@ -16,6 +17,28 @@ pub fn check(cx: &Ctxt, cont: &mut Container, derive: Derive) {
     check_from_and_try_from(cx, cont);
 }
 
+/// Remote derive definition type must have either all of the generics of the
+/// remote type:
+///
+///     #[serde(remote = "Generic")]
+///     struct Generic<T> {…}
+///
+/// or none of them, i.e. defining impls for one concrete instantiation of the
+/// remote type only:
+///
+///     #[serde(remote = "Generic<T>")]
+///     struct ConcreteDef {…}
+///
+fn check_remote_generic(cx: &Ctxt, cont: &Container) {
+    if let Some(remote) = cont.attrs.remote() {
+        let local_has_generic = !cont.generics.params.is_empty();
+        let remote_has_generic = !remote.segments.last().unwrap().arguments.is_none();
+        if local_has_generic && remote_has_generic {
+            cx.error_spanned_by(remote, "remove generic parameters from this path");
+        }
+    }
+}
+
 /// Getters are only allowed inside structs (not enums) with the `remote`
 /// attribute.
 fn check_getter(cx: &Ctxt, cont: &Container) {

serde_derive/src/lib.rs

@@ -13,7 +13,7 @@
 //!
 //! [https://serde.rs/derive.html]: https://serde.rs/derive.html
 
-#![doc(html_root_url = "https://docs.rs/serde_derive/1.0.137")]
+#![doc(html_root_url = "https://docs.rs/serde_derive/1.0.149")]
 #![allow(unknown_lints, bare_trait_objects)]
 // Ignored clippy lints
 #![allow(
@@ -43,7 +43,6 @@
     clippy::enum_glob_use,
     clippy::indexing_slicing,
     clippy::items_after_statements,
-    clippy::let_underscore_drop,
     clippy::manual_assert,
     clippy::map_err_ignore,
     clippy::match_same_arms,
@@ -85,6 +84,7 @@ mod de;
 mod dummy;
 mod pretend;
 mod ser;
+mod this;
 mod try;
 
 #[proc_macro_derive(Serialize, attributes(serde))]

serde_derive/src/pretend.rs

@@ -97,7 +97,7 @@ fn pretend_fields_used_struct_packed(cont: &Container, fields: &[Field]) -> Toke
 
     let members = fields.iter().map(|field| &field.member).collect::<Vec<_>>();
 
-    #[cfg(ptr_addr_of)]
+    #[cfg(not(no_ptr_addr_of))]
     {
         quote! {
             match _serde::__private::None::<&#type_ident #ty_generics> {
@@ -111,7 +111,7 @@ fn pretend_fields_used_struct_packed(cont: &Container, fields: &[Field]) -> Toke
         }
     }
 
-    #[cfg(not(ptr_addr_of))]
+    #[cfg(no_ptr_addr_of)]
     {
         let placeholders = (0usize..).map(|i| format_ident!("__v{}", i));
 

serde_derive/src/ser.rs

@@ -8,6 +8,7 @@ use fragment::{Fragment, Match, Stmts};
 use internals::ast::{Container, Data, Field, Style, Variant};
 use internals::{attr, replace_receiver, Ctxt, Derive};
 use pretend;
+use this;
 
 pub fn expand_derive_serialize(
     input: &mut syn::DeriveInput,
@@ -82,9 +83,13 @@ struct Parameters {
     self_var: Ident,
 
     /// Path to the type the impl is for. Either a single `Ident` for local
-    /// types or `some::remote::Ident` for remote types. Does not include
+    /// types (does not include generic parameters) or `some::remote::Path` for
-    /// generic parameters.
+    /// remote types.
-    this: syn::Path,
+    this_type: syn::Path,
+
+    /// Same as `this_type` but using `::<T>` for generic parameters for use in
+    /// expression position.
+    this_value: syn::Path,
 
     /// Generics including any explicit and inferred bounds for the impl.
     generics: syn::Generics,
@@ -105,18 +110,15 @@ impl Parameters {
             Ident::new("self", Span::call_site())
         };
 
-        let this = match cont.attrs.remote() {
+        let this_type = this::this_type(cont);
-            Some(remote) => remote.clone(),
+        let this_value = this::this_value(cont);
-            None => cont.ident.clone().into(),
-        };
-
         let is_packed = cont.attrs.is_packed();
-
         let generics = build_generics(cont);
 
         Parameters {
             self_var,
-            this,
+            this_type,
+            this_value,
             generics,
             is_remote,
             is_packed,
@@ -126,7 +128,7 @@ impl Parameters {
     /// Type name to use in error messages and `&'static str` arguments to
     /// various Serializer methods.
     fn type_name(&self) -> String {
-        self.this.segments.last().unwrap().ident.to_string()
+        self.this_type.segments.last().unwrap().ident.to_string()
     }
 }
 
@@ -427,7 +429,7 @@ fn serialize_variant(
     variant_index: u32,
     cattrs: &attr::Container,
 ) -> TokenStream {
-    let this = &params.this;
+    let this_value = &params.this_value;
     let variant_ident = &variant.ident;
 
     if variant.attrs.skip_serializing() {
@@ -445,32 +447,32 @@ fn serialize_variant(
             Style::Struct => quote!({ .. }),
         };
         quote! {
-            #this::#variant_ident #fields_pat => #skipped_err,
+            #this_value::#variant_ident #fields_pat => #skipped_err,
         }
     } else {
         // variant wasn't skipped
         let case = match variant.style {
             Style::Unit => {
                 quote! {
-                    #this::#variant_ident
+                    #this_value::#variant_ident
                 }
             }
             Style::Newtype => {
                 quote! {
-                    #this::#variant_ident(ref __field0)
+                    #this_value::#variant_ident(ref __field0)
                 }
             }
             Style::Tuple => {
                 let field_names = (0..variant.fields.len())
                     .map(|i| Ident::new(&format!("__field{}", i), Span::call_site()));
                 quote! {
-                    #this::#variant_ident(#(ref #field_names),*)
+                    #this_value::#variant_ident(#(ref #field_names),*)
                 }
             }
             Style::Struct => {
                 let members = variant.fields.iter().map(|f| &f.member);
                 quote! {
-                    #this::#variant_ident { #(ref #members),* }
+                    #this_value::#variant_ident { #(ref #members),* }
                 }
             }
         };
@@ -640,7 +642,7 @@ fn serialize_adjacently_tagged_variant(
     tag: &str,
     content: &str,
 ) -> Fragment {
-    let this = &params.this;
+    let this_type = &params.this_type;
     let type_name = cattrs.name().serialize_name();
     let variant_name = variant.attrs.name().serialize_name();
 
@@ -719,7 +721,7 @@ fn serialize_adjacently_tagged_variant(
     quote_block! {
         struct __AdjacentlyTagged #wrapper_generics #where_clause {
             data: (#(&'__a #fields_ty,)*),
-            phantom: _serde::__private::PhantomData<#this #ty_generics>,
+            phantom: _serde::__private::PhantomData<#this_type #ty_generics>,
         }
 
         impl #wrapper_impl_generics _serde::Serialize for __AdjacentlyTagged #wrapper_ty_generics #where_clause {
@@ -741,7 +743,7 @@ fn serialize_adjacently_tagged_variant(
         try!(_serde::ser::SerializeStruct::serialize_field(
             &mut __struct, #content, &__AdjacentlyTagged {
                 data: (#(#fields_ident,)*),
-                phantom: _serde::__private::PhantomData::<#this #ty_generics>,
+                phantom: _serde::__private::PhantomData::<#this_type #ty_generics>,
             }));
         _serde::ser::SerializeStruct::end(__struct)
     }
@@ -866,8 +868,8 @@ enum StructVariant<'a> {
     Untagged,
 }
 
-fn serialize_struct_variant<'a>(
+fn serialize_struct_variant(
-    context: StructVariant<'a>,
+    context: StructVariant,
     params: &Parameters,
     fields: &[Field],
     name: &str,
@@ -950,8 +952,8 @@ fn serialize_struct_variant<'a>(
     }
 }
 
-fn serialize_struct_variant_with_flatten<'a>(
+fn serialize_struct_variant_with_flatten(
-    context: StructVariant<'a>,
+    context: StructVariant,
     params: &Parameters,
     fields: &[Field],
     name: &str,
@@ -971,7 +973,7 @@ fn serialize_struct_variant_with_flatten<'a>(
             variant_index,
             variant_name,
         } => {
-            let this = &params.this;
+            let this_type = &params.this_type;
             let fields_ty = fields.iter().map(|f| &f.ty);
             let members = &fields.iter().map(|f| &f.member).collect::<Vec<_>>();
 
@@ -982,7 +984,7 @@ fn serialize_struct_variant_with_flatten<'a>(
             quote_block! {
                 struct __EnumFlatten #wrapper_generics #where_clause {
                     data: (#(&'__a #fields_ty,)*),
-                    phantom: _serde::__private::PhantomData<#this #ty_generics>,
+                    phantom: _serde::__private::PhantomData<#this_type #ty_generics>,
                 }
 
                 impl #wrapper_impl_generics _serde::Serialize for __EnumFlatten #wrapper_ty_generics #where_clause {
@@ -1006,7 +1008,7 @@ fn serialize_struct_variant_with_flatten<'a>(
                     #variant_name,
                     &__EnumFlatten {
                         data: (#(#members,)*),
-                        phantom: _serde::__private::PhantomData::<#this #ty_generics>,
+                        phantom: _serde::__private::PhantomData::<#this_type #ty_generics>,
                     })
             }
         }
@@ -1192,7 +1194,7 @@ fn wrap_serialize_with(
     field_tys: &[&syn::Type],
     field_exprs: &[TokenStream],
 ) -> TokenStream {
-    let this = &params.this;
+    let this_type = &params.this_type;
     let (_, ty_generics, where_clause) = params.generics.split_for_impl();
 
     let wrapper_generics = if field_exprs.is_empty() {
@@ -1212,7 +1214,7 @@ fn wrap_serialize_with(
     quote!({
         struct __SerializeWith #wrapper_impl_generics #where_clause {
             values: (#(&'__a #field_tys, )*),
-            phantom: _serde::__private::PhantomData<#this #ty_generics>,
+            phantom: _serde::__private::PhantomData<#this_type #ty_generics>,
         }
 
         impl #wrapper_impl_generics _serde::Serialize for __SerializeWith #wrapper_ty_generics #where_clause {
@@ -1226,7 +1228,7 @@ fn wrap_serialize_with(
 
         &__SerializeWith {
             values: (#(#field_exprs, )*),
-            phantom: _serde::__private::PhantomData::<#this #ty_generics>,
+            phantom: _serde::__private::PhantomData::<#this_type #ty_generics>,
         }
     })
 }

serde_derive/src/this.rs

@@ -0,0 +1,32 @@
+use internals::ast::Container;
+use syn::{Path, PathArguments, Token};
+
+pub fn this_type(cont: &Container) -> Path {
+    if let Some(remote) = cont.attrs.remote() {
+        let mut this = remote.clone();
+        for segment in &mut this.segments {
+            if let PathArguments::AngleBracketed(arguments) = &mut segment.arguments {
+                arguments.colon2_token = None;
+            }
+        }
+        this
+    } else {
+        Path::from(cont.ident.clone())
+    }
+}
+
+pub fn this_value(cont: &Container) -> Path {
+    if let Some(remote) = cont.attrs.remote() {
+        let mut this = remote.clone();
+        for segment in &mut this.segments {
+            if let PathArguments::AngleBracketed(arguments) = &mut segment.arguments {
+                if arguments.colon2_token.is_none() {
+                    arguments.colon2_token = Some(Token![::](arguments.lt_token.span));
+                }
+            }
+        }
+        this
+    } else {
+        Path::from(cont.ident.clone())
+    }
+}

serde_derive_internals/Cargo.toml

@@ -2,14 +2,14 @@
 name = "serde_derive_internals"
 version = "0.26.0" # remember to update html_root_url
 authors = ["Erick Tryzelaar <erick.tryzelaar@gmail.com>", "David Tolnay <dtolnay@gmail.com>"]
-rust-version = "1.31"
-license = "MIT OR Apache-2.0"
 description = "AST representation used by Serde derive macros. Unstable."
-homepage = "https://serde.rs"
-repository = "https://github.com/serde-rs/serde"
 documentation = "https://docs.rs/serde_derive_internals"
-keywords = ["serde", "serialization"]
+homepage = "https://serde.rs"
 include = ["lib.rs", "src/**/*.rs", "LICENSE-APACHE", "LICENSE-MIT"]
+keywords = ["serde", "serialization"]
+license = "MIT OR Apache-2.0"
+repository = "https://github.com/serde-rs/serde"
+rust-version = "1.31"
 
 [lib]
 path = "lib.rs"
@@ -17,7 +17,7 @@ path = "lib.rs"
 [dependencies]
 proc-macro2 = "1.0"
 quote = "1.0"
-syn = { version = "1.0.90", default-features = false, features = ["derive", "parsing", "printing", "clone-impls"] }
+syn = { version = "1.0.104", default-features = false, features = ["derive", "parsing", "printing", "clone-impls"] }
 
 [package.metadata.docs.rs]
 targets = ["x86_64-unknown-linux-gnu"]

serde_derive_internals/lib.rs

@@ -22,7 +22,6 @@
     clippy::doc_markdown,
     clippy::enum_glob_use,
     clippy::items_after_statements,
-    clippy::let_underscore_drop,
     clippy::manual_assert,
     clippy::match_same_arms,
     // clippy bug: https://github.com/rust-lang/rust-clippy/issues/6984

serde_test/Cargo.toml

@@ -1,17 +1,18 @@
 [package]
 name = "serde_test"
-version = "1.0.137" # remember to update html_root_url
+version = "1.0.149" # remember to update html_root_url
 authors = ["Erick Tryzelaar <erick.tryzelaar@gmail.com>", "David Tolnay <dtolnay@gmail.com>"]
-rust-version = "1.13"
-license = "MIT OR Apache-2.0"
-description = "Token De/Serializer for testing De/Serialize implementations"
-homepage = "https://serde.rs"
-repository = "https://github.com/serde-rs/serde"
-documentation = "https://docs.serde.rs/serde_test/"
-keywords = ["serde", "serialization"]
-readme = "crates-io.md"
-include = ["build.rs", "src/**/*.rs", "crates-io.md", "README.md", "LICENSE-APACHE", "LICENSE-MIT"]
 build = "build.rs"
+categories = ["development-tools::testing"]
+description = "Token De/Serializer for testing De/Serialize implementations"
+documentation = "https://docs.serde.rs/serde_test/"
+homepage = "https://serde.rs"
+include = ["build.rs", "src/**/*.rs", "crates-io.md", "README.md", "LICENSE-APACHE", "LICENSE-MIT"]
+keywords = ["serde", "serialization", "testing", "dev-dependencies"]
+license = "MIT OR Apache-2.0"
+readme = "crates-io.md"
+repository = "https://github.com/serde-rs/serde"
+rust-version = "1.13"
 
 [dependencies]
 serde = { version = "1.0.60", path = "../serde" }

serde_test/build.rs

@@ -13,8 +13,8 @@ fn main() {
 
     // #[track_caller] stabilized in Rust 1.46:
     // https://blog.rust-lang.org/2020/08/27/Rust-1.46.0.html#track_caller
-    if minor >= 46 {
+    if minor < 46 {
-        println!("cargo:rustc-cfg=track_caller");
+        println!("cargo:rustc-cfg=no_track_caller");
     }
 }
 

serde_test/src/assert.rs

@@ -28,7 +28,7 @@ use std::fmt::Debug;
 ///     Token::StructEnd,
 /// ]);
 /// ```
-#[cfg_attr(track_caller, track_caller)]
+#[cfg_attr(not(no_track_caller), track_caller)]
 pub fn assert_tokens<'de, T>(value: &T, tokens: &'de [Token])
 where
     T: Serialize + Deserialize<'de> + PartialEq + Debug,
@@ -59,7 +59,7 @@ where
 ///     Token::StructEnd,
 /// ]);
 /// ```
-#[cfg_attr(track_caller, track_caller)]
+#[cfg_attr(not(no_track_caller), track_caller)]
 pub fn assert_ser_tokens<T: ?Sized>(value: &T, tokens: &[Token])
 where
     T: Serialize,
@@ -112,7 +112,7 @@ where
 ///     assert_ser_tokens_error(&example, expected, error);
 /// }
 /// ```
-#[cfg_attr(track_caller, track_caller)]
+#[cfg_attr(not(no_track_caller), track_caller)]
 pub fn assert_ser_tokens_error<T: ?Sized>(value: &T, tokens: &[Token], error: &str)
 where
     T: Serialize,
@@ -150,7 +150,7 @@ where
 ///     Token::StructEnd,
 /// ]);
 /// ```
-#[cfg_attr(track_caller, track_caller)]
+#[cfg_attr(not(no_track_caller), track_caller)]
 pub fn assert_de_tokens<'de, T>(value: &T, tokens: &'de [Token])
 where
     T: Deserialize<'de> + PartialEq + Debug,
@@ -203,7 +203,7 @@ where
 ///     "unknown field `x`, expected `a` or `b`",
 /// );
 /// ```
-#[cfg_attr(track_caller, track_caller)]
+#[cfg_attr(not(no_track_caller), track_caller)]
 pub fn assert_de_tokens_error<'de, T>(tokens: &'de [Token], error: &str)
 where
     T: Deserialize<'de>,

serde_test/src/lib.rs

@@ -144,7 +144,7 @@
 //! # }
 //! ```
 
-#![doc(html_root_url = "https://docs.rs/serde_test/1.0.137")]
+#![doc(html_root_url = "https://docs.rs/serde_test/1.0.149")]
 #![cfg_attr(feature = "cargo-clippy", allow(renamed_and_removed_lints))]
 // Ignored clippy lints
 #![cfg_attr(feature = "cargo-clippy", allow(float_cmp, needless_doctest_main))]

test_suite/Cargo.toml

@@ -2,9 +2,9 @@
 name = "serde_test_suite"
 version = "0.0.0"
 authors = ["Erick Tryzelaar <erick.tryzelaar@gmail.com>", "David Tolnay <dtolnay@gmail.com>"]
+build = "build.rs"
 edition = "2018"
 publish = false
-build = "build.rs"
 
 [features]
 expandtest = []
@@ -24,4 +24,4 @@ rustversion = "1.0"
 serde = { path = "../serde", features = ["rc", "derive"] }
 serde_derive = { path = "../serde_derive", features = ["deserialize_in_place"] }
 serde_test = { path = "../serde_test" }
-trybuild = { version = "1.0.49", features = ["diff"] }
+trybuild = { version = "1.0.66", features = ["diff"] }

test_suite/no_std/Cargo.toml

@@ -1,6 +1,7 @@
 [package]
 name = "serde_derive_tests_no_std"
 version = "0.0.0"
+authors = ["David Tolnay <dtolnay@gmail.com>"]
 edition = "2018"
 publish = false
 

test_suite/tests/test_annotations.rs

@@ -1235,7 +1235,7 @@ fn serialize_variant_as_string<S>(f1: &str, f2: &u8, serializer: S) -> Result<S:
 where
     S: Serializer,
 {
-    serializer.serialize_str(format!("{};{:?}", f1, f2).as_str())
+    serializer.serialize_str(format!("{f1};{f2:?}").as_str())
 }
 
 fn deserialize_string_as_variant<'de, D>(deserializer: D) -> Result<(String, u8), D::Error>
@@ -1244,22 +1244,17 @@ where
 {
     let s = String::deserialize(deserializer)?;
     let mut pieces = s.split(';');
-    let f1 = match pieces.next() {
+    let Some(f1) = pieces.next() else {
-        Some(x) => x,
+        return Err(de::Error::invalid_length(0, &"2"));
-        None => return Err(de::Error::invalid_length(0, &"2")),
     };
-    let f2 = match pieces.next() {
+    let Some(f2) = pieces.next() else {
-        Some(x) => x,
+        return Err(de::Error::invalid_length(1, &"2"));
-        None => return Err(de::Error::invalid_length(1, &"2")),
     };
-    let f2 = match f2.parse() {
+    let Ok(f2) = f2.parse() else {
-        Ok(n) => n,
+        return Err(de::Error::invalid_value(
-        Err(_) => {
+            Unexpected::Str(f2),
-            return Err(de::Error::invalid_value(
+            &"an 8-bit signed integer",
-                Unexpected::Str(f2),
+        ));
-                &"an 8-bit signed integer",
-            ));
-        }
     };
     Ok((f1.into(), f2))
 }
@@ -2302,6 +2297,25 @@ fn test_internally_tagged_enum_containing_flatten() {
     );
 }
 
+#[test]
+fn test_internally_tagged_enum_new_type_with_unit() {
+    #[derive(Serialize, Deserialize, PartialEq, Debug)]
+    #[serde(tag = "t")]
+    enum Data {
+        A(()),
+    }
+
+    assert_tokens(
+        &Data::A(()),
+        &[
+            Token::Map { len: Some(1) },
+            Token::Str("t"),
+            Token::Str("A"),
+            Token::MapEnd,
+        ],
+    );
+}
+
 #[test]
 fn test_adjacently_tagged_enum_containing_flatten() {
     #[derive(Serialize, Deserialize, PartialEq, Debug)]

test_suite/tests/test_de.rs

@@ -5,6 +5,7 @@
     clippy::empty_enum,
     clippy::manual_assert,
     clippy::needless_pass_by_value,
+    clippy::uninlined_format_args,
     clippy::unreadable_literal
 )]
 #![cfg_attr(feature = "unstable", feature(never_type))]

test_suite/tests/test_remote.rs

@@ -74,6 +74,21 @@ mod remote {
             &self.b
         }
     }
+
+    pub struct StructGeneric<T> {
+        pub value: T,
+    }
+
+    impl<T> StructGeneric<T> {
+        #[allow(dead_code)]
+        pub fn get_value(&self) -> &T {
+            &self.value
+        }
+    }
+
+    pub enum EnumGeneric<T> {
+        Variant(T),
+    }
 }
 
 #[derive(Serialize, Deserialize)]
@@ -104,6 +119,12 @@ struct Test {
 
     #[serde(with = "StructPubDef")]
     struct_pub: remote::StructPub,
+
+    #[serde(with = "StructConcrete")]
+    struct_concrete: remote::StructGeneric<u8>,
+
+    #[serde(with = "EnumConcrete")]
+    enum_concrete: remote::EnumGeneric<u8>,
 }
 
 #[derive(Serialize, Deserialize)]
@@ -157,6 +178,25 @@ struct StructPubDef {
     b: remote::Unit,
 }
 
+#[derive(Serialize, Deserialize)]
+#[serde(remote = "remote::StructGeneric")]
+struct StructGenericWithGetterDef<T> {
+    #[serde(getter = "remote::StructGeneric::get_value")]
+    value: T,
+}
+
+#[derive(Serialize, Deserialize)]
+#[serde(remote = "remote::StructGeneric<u8>")]
+struct StructConcrete {
+    value: u8,
+}
+
+#[derive(Serialize, Deserialize)]
+#[serde(remote = "remote::EnumGeneric<u8>")]
+enum EnumConcrete {
+    Variant(u8),
+}
+
 impl From<PrimitivePrivDef> for remote::PrimitivePriv {
     fn from(def: PrimitivePrivDef) -> Self {
         remote::PrimitivePriv::new(def.0)
@@ -180,3 +220,9 @@ impl From<StructPrivDef> for remote::StructPriv {
         remote::StructPriv::new(def.a, def.b)
     }
 }
+
+impl<T> From<StructGenericWithGetterDef<T>> for remote::StructGeneric<T> {
+    fn from(def: StructGenericWithGetterDef<T>) -> Self {
+        remote::StructGeneric { value: def.value }
+    }
+}

test_suite/tests/test_ser.rs

@@ -13,7 +13,7 @@ use std::sync::atomic::{
     AtomicBool, AtomicI16, AtomicI32, AtomicI8, AtomicIsize, AtomicU16, AtomicU32, AtomicU8,
     AtomicUsize,
 };
-use std::sync::{Arc, Weak as ArcWeak};
+use std::sync::{Arc, Mutex, RwLock, Weak as ArcWeak};
 use std::time::{Duration, UNIX_EPOCH};
 
 #[cfg(unix)]
@@ -800,17 +800,14 @@ fn test_never_result() {
 #[test]
 #[cfg(unix)]
 fn test_cannot_serialize_paths() {
-    let path = unsafe { str::from_utf8_unchecked(b"Hello \xF0\x90\x80World") };
+    use std::ffi::OsStr;
+    use std::os::unix::ffi::OsStrExt;
+
     assert_ser_tokens_error(
-        &Path::new(path),
+        &Path::new(OsStr::from_bytes(b"Hello \xF0\x90\x80World")),
         &[],
         "path contains invalid UTF-8 characters",
     );
-
-    let mut path_buf = PathBuf::new();
-    path_buf.push(path);
-
-    assert_ser_tokens_error(&path_buf, &[], "path contains invalid UTF-8 characters");
 }
 
 #[test]
@@ -850,3 +847,39 @@ fn test_integer128() {
 
     assert_ser_tokens_error(&1u128, &[], "u128 is not supported");
 }
+
+#[test]
+fn test_refcell_dst() {
+    assert_ser_tokens(
+        &RefCell::new([true]) as &RefCell<[bool]>,
+        &[
+            Token::Seq { len: Some(1) },
+            Token::Bool(true),
+            Token::SeqEnd,
+        ],
+    );
+}
+
+#[test]
+fn test_mutex_dst() {
+    assert_ser_tokens(
+        &Mutex::new([true]) as &Mutex<[bool]>,
+        &[
+            Token::Seq { len: Some(1) },
+            Token::Bool(true),
+            Token::SeqEnd,
+        ],
+    );
+}
+
+#[test]
+fn test_rwlock_dst() {
+    assert_ser_tokens(
+        &RwLock::new([true]) as &RwLock<[bool]>,
+        &[
+            Token::Seq { len: Some(1) },
+            Token::Bool(true),
+            Token::SeqEnd,
+        ],
+    );
+}

test_suite/tests/ui/remote/double_generic.rs

@@ -0,0 +1,17 @@
+use serde_derive::{Deserialize, Serialize};
+
+mod remote {
+    pub struct Struct<T, U> {
+        pub t: T,
+        pub u: U,
+    }
+}
+
+#[derive(Serialize, Deserialize)]
+#[serde(remote = "remote::StructGeneric<u8>")]
+struct StructDef<U> {
+    t: u8,
+    u: U,
+}
+
+fn main() {}

test_suite/tests/ui/remote/double_generic.stderr

@@ -0,0 +1,5 @@
+error: remove generic parameters from this path
+  --> tests/ui/remote/double_generic.rs:11:18
+   |
+11 | #[serde(remote = "remote::StructGeneric<u8>")]
+   |                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^

test_suite/tests/ui/remote/wrong_ser.stderr

@@ -1,17 +1,17 @@
 error[E0308]: mismatched types
-  --> tests/ui/remote/wrong_ser.rs:9:10
+ --> tests/ui/remote/wrong_ser.rs:9:10
-   |
+  |
-9  | #[derive(Serialize)]
+9 | #[derive(Serialize)]
-   |          ^^^^^^^^^
+  |          ^^^^^^^^^
-   |          |
+  |          |
-   |          expected `u8`, found `u16`
+  |          expected `u8`, found `u16`
-   |          arguments to this function are incorrect
+  |          arguments to this function are incorrect
-   |
+  |
-   = note: expected reference `&u8`
+  = note: expected reference `&u8`
-              found reference `&u16`
+             found reference `&u16`
 note: function defined here
-  --> $WORKSPACE/serde/src/private/ser.rs
+ --> $WORKSPACE/serde/src/private/ser.rs
-   |
+  |
-   | pub fn constrain<T: ?Sized>(t: &T) -> &T {
+  | pub fn constrain<T: ?Sized>(t: &T) -> &T {
-   |        ^^^^^^^^^
+  |        ^^^^^^^^^
-   = note: this error originates in the derive macro `Serialize` (in Nightly builds, run with -Z macro-backtrace for more info)
+  = note: this error originates in the derive macro `Serialize` (in Nightly builds, run with -Z macro-backtrace for more info)