Release 1.0.180

Delete tombstones of the `__private` module

.github/workflows/ci.yml

@@ -62,6 +62,7 @@ jobs:
       - run: cd serde && cargo build --no-default-features
       - run: cd serde && cargo build --no-default-features --features alloc
       - run: cd serde && cargo build --no-default-features --features rc,alloc
+      - run: cd serde && cargo build --no-default-features --features unstable
       - run: cd serde && cargo test --features derive,rc,unstable
       - run: cd test_suite/no_std && cargo build
         if: matrix.os != 'windows'
@@ -76,7 +77,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        rust: [1.19.0, 1.20.0, 1.21.0, 1.25.0, 1.26.0, 1.34.0]
+        rust: [1.31.0, 1.34.0]
     timeout-minutes: 45
     steps:
       - uses: actions/checkout@v3
@@ -87,24 +88,6 @@ jobs:
       - run: cd serde && cargo build --no-default-features
       - run: cd serde && cargo build
 
-  more:
-    name: Rust ${{matrix.rust}}
-    runs-on: ubuntu-latest
-    strategy:
-      fail-fast: false
-      matrix:
-        rust: [1.27.0, 1.28.0]
-    timeout-minutes: 45
-    steps:
-      - uses: actions/checkout@v3
-      - uses: dtolnay/rust-toolchain@master
-        with:
-          toolchain: ${{matrix.rust}}
-        # Work around failing to parse manifest because editions are unstable.
-      - run: sed -i /test_suite/d Cargo.toml
-      - run: cd serde && cargo build --no-default-features
-      - run: cd serde && cargo build
-
   derive:
     name: Rust 1.56.0
     runs-on: ubuntu-latest
@@ -126,6 +109,29 @@ jobs:
       - uses: dtolnay/rust-toolchain@1.36.0
       - run: cd serde && cargo build --no-default-features --features alloc
 
+  precompiled:
+    name: Precompiled
+    runs-on: ubuntu-latest
+    timeout-minutes: 45
+    steps:
+      - uses: actions/checkout@v3
+      - uses: dtolnay/rust-toolchain@nightly
+        with:
+          components: rust-src
+          targets: x86_64-unknown-linux-musl
+      - run: precompiled/build.sh
+      - name: replace serde_derive dependency with precompiled
+        run: |
+          # FIXME: consider using `cargo rm serde_derive` but it's currently broken
+          # https://github.com/rust-lang/cargo/issues/12419
+          sed -i '/serde_derive =/d' serde/Cargo.toml
+          sed -i '/derive = \["serde_derive"\]/d' serde/Cargo.toml
+          sed -i '/"serde_derive"/d' Cargo.toml
+          sed -i '/\[workspace\]/d' precompiled/serde_derive/Cargo.toml
+          cargo add --dev serde_derive --path precompiled/serde_derive --manifest-path test_suite/Cargo.toml
+          git diff
+      - run: cd test_suite && cargo test --features unstable -- --skip ui --exact
+
   macos:
     name: macOS
     runs-on: macos-latest

README.md

@@ -1,12 +1,12 @@
-# Serde   [![Build Status]][actions] [![Latest Version]][crates.io] [![serde: rustc 1.19+]][Rust 1.19] [![serde_derive: rustc 1.56+]][Rust 1.56]
+# Serde   [![Build Status]][actions] [![Latest Version]][crates.io] [![serde: rustc 1.31+]][Rust 1.31] [![serde_derive: rustc 1.56+]][Rust 1.56]
 
 [Build Status]: https://img.shields.io/github/actions/workflow/status/serde-rs/serde/ci.yml?branch=master
 [actions]: https://github.com/serde-rs/serde/actions?query=branch%3Amaster
 [Latest Version]: https://img.shields.io/crates/v/serde.svg
 [crates.io]: https://crates.io/crates/serde
-[serde: rustc 1.19+]: https://img.shields.io/badge/serde-rustc_1.19+-lightgray.svg
+[serde: rustc 1.31+]: https://img.shields.io/badge/serde-rustc_1.31+-lightgray.svg
 [serde_derive: rustc 1.56+]: https://img.shields.io/badge/serde_derive-rustc_1.56+-lightgray.svg
-[Rust 1.19]: https://blog.rust-lang.org/2017/07/20/Rust-1.19.html
+[Rust 1.31]: https://blog.rust-lang.org/2018/12/06/Rust-1.31-and-rust-2018.html
 [Rust 1.56]: https://blog.rust-lang.org/2021/10/21/Rust-1.56.0.html
 
 **Serde is a framework for *ser*ializing and *de*serializing Rust data structures efficiently and generically.**

precompiled/bin/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "serde_derive"
-version = "1.0.176"
+version = "1.0.180"
 authors = ["David Tolnay <dtolnay@gmail.com>"]
 publish = false
 
@@ -14,4 +14,4 @@ path = "main.rs"
 [dependencies]
 proc-macro2 = "1"
 quote = { version = "1", default-features = false }
-syn = { version = "2.0.25", default-features = false, features = ["clone-impls", "derive", "full", "parsing", "printing"] }
+syn = { version = "2.0.28", default-features = false, features = ["clone-impls", "derive", "full", "parsing", "printing"] }

precompiled/serde_derive/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "serde_derive"
-version = "1.0.176"
+version = "1.0.180"
 authors = ["David Tolnay <dtolnay@gmail.com>"]
 categories = ["no-std", "no-std::no-alloc"]
 description = "Implementation of #[derive(Serialize, Deserialize)]"
@@ -24,7 +24,7 @@ proc-macro = true
 [target.'cfg(not(all(target_arch = "x86_64", target_os = "linux", target_env = "gnu")))'.dependencies]
 proc-macro2 = "1"
 quote = "1"
-syn = "2.0.25"
+syn = "2.0.28"
 
 [dev-dependencies]
 serde = { version = "1", path = "../../serde" }

precompiled/serde_derive/src/lib.rs

@@ -13,8 +13,7 @@
 //!
 //! [https://serde.rs/derive.html]: https://serde.rs/derive.html
 
-#![doc(html_root_url = "https://docs.rs/serde_derive/1.0.176")]
-#![allow(unknown_lints, bare_trait_objects)]
+#![doc(html_root_url = "https://docs.rs/serde_derive/1.0.180")]
 
 #[cfg(not(all(target_arch = "x86_64", target_os = "linux", target_env = "gnu")))]
 include!("lib_from_source.rs");

precompiled/serde_derive/src/lib_from_source.rs

@@ -14,7 +14,6 @@ mod internals;
 mod pretend;
 mod ser;
 mod this;
-mod try;
 
 use proc_macro::TokenStream;
 use syn::{parse_macro_input, DeriveInput};

precompiled/serde_derive/src/try.rs

@@ -1 +0,0 @@
-../../../serde_derive/src/try.rs

serde/Cargo.toml

@@ -1,20 +1,21 @@
 [package]
 name = "serde"
-version = "1.0.176" # remember to update html_root_url and serde_derive dependency
+version = "1.0.180" # remember to update html_root_url and serde_derive dependency
 authors = ["Erick Tryzelaar <erick.tryzelaar@gmail.com>", "David Tolnay <dtolnay@gmail.com>"]
 build = "build.rs"
 categories = ["encoding", "no-std", "no-std::no-alloc"]
 description = "A generic serialization/deserialization framework"
 documentation = "https://docs.rs/serde"
+edition = "2018"
 homepage = "https://serde.rs"
 keywords = ["serde", "serialization", "no_std"]
 license = "MIT OR Apache-2.0"
 readme = "crates-io.md"
 repository = "https://github.com/serde-rs/serde"
-rust-version = "1.19"
+rust-version = "1.31"
 
 [dependencies]
-serde_derive = { version = "=1.0.176", optional = true, path = "../serde_derive" }
+serde_derive = { version = "=1.0.180", optional = true, path = "../serde_derive" }
 
 [dev-dependencies]
 serde_derive = { version = "1", path = "../serde_derive" }

serde/build.rs

@@ -16,68 +16,6 @@ fn main() {
     let target = env::var("TARGET").unwrap();
     let emscripten = target == "asmjs-unknown-emscripten" || target == "wasm32-unknown-emscripten";
 
-    // std::collections::Bound was stabilized in Rust 1.17
-    // but it was moved to core::ops later in Rust 1.26:
-    // https://doc.rust-lang.org/core/ops/enum.Bound.html
-    if minor < 26 {
-        println!("cargo:rustc-cfg=no_ops_bound");
-        if minor < 17 {
-            println!("cargo:rustc-cfg=no_collections_bound");
-        }
-    }
-
-    // core::cmp::Reverse stabilized in Rust 1.19:
-    // https://doc.rust-lang.org/stable/core/cmp/struct.Reverse.html
-    if minor < 19 {
-        println!("cargo:rustc-cfg=no_core_reverse");
-    }
-
-    // CString::into_boxed_c_str and PathBuf::into_boxed_path stabilized in Rust 1.20:
-    // https://doc.rust-lang.org/std/ffi/struct.CString.html#method.into_boxed_c_str
-    // https://doc.rust-lang.org/std/path/struct.PathBuf.html#method.into_boxed_path
-    if minor < 20 {
-        println!("cargo:rustc-cfg=no_de_boxed_c_str");
-        println!("cargo:rustc-cfg=no_de_boxed_path");
-    }
-
-    // From<Box<T>> for Rc<T> / Arc<T> stabilized in Rust 1.21:
-    // https://doc.rust-lang.org/std/rc/struct.Rc.html#impl-From<Box<T>>
-    // https://doc.rust-lang.org/std/sync/struct.Arc.html#impl-From<Box<T>>
-    if minor < 21 {
-        println!("cargo:rustc-cfg=no_de_rc_dst");
-    }
-
-    // Duration available in core since Rust 1.25:
-    // https://blog.rust-lang.org/2018/03/29/Rust-1.25.html#library-stabilizations
-    if minor < 25 {
-        println!("cargo:rustc-cfg=no_core_duration");
-    }
-
-    // 128-bit integers stabilized in Rust 1.26:
-    // https://blog.rust-lang.org/2018/05/10/Rust-1.26.html
-    //
-    // Disabled on Emscripten targets before Rust 1.40 since
-    // Emscripten did not support 128-bit integers until Rust 1.40
-    // (https://github.com/rust-lang/rust/pull/65251)
-    if minor < 26 || emscripten && minor < 40 {
-        println!("cargo:rustc-cfg=no_integer128");
-    }
-
-    // Inclusive ranges methods stabilized in Rust 1.27:
-    // https://github.com/rust-lang/rust/pull/50758
-    // Also Iterator::try_for_each:
-    // https://blog.rust-lang.org/2018/06/21/Rust-1.27.html#library-stabilizations
-    if minor < 27 {
-        println!("cargo:rustc-cfg=no_range_inclusive");
-        println!("cargo:rustc-cfg=no_iterator_try_fold");
-    }
-
-    // Non-zero integers stabilized in Rust 1.28:
-    // https://blog.rust-lang.org/2018/08/02/Rust-1.28.html#library-stabilizations
-    if minor < 28 {
-        println!("cargo:rustc-cfg=no_num_nonzero");
-    }
-
     // TryFrom, Atomic types, non-zero signed integers, and SystemTime::checked_add
     // stabilized in Rust 1.34:
     // https://blog.rust-lang.org/2019/04/11/Rust-1.34.0.html#tryfrom-and-tryinto
@@ -89,6 +27,13 @@ fn main() {
         println!("cargo:rustc-cfg=no_relaxed_trait_bounds");
     }
 
+    // Disabled on Emscripten targets before Rust 1.40 since
+    // Emscripten did not support 128-bit integers until Rust 1.40
+    // (https://github.com/rust-lang/rust/pull/65251)
+    if emscripten && minor < 40 {
+        println!("cargo:rustc-cfg=no_integer128");
+    }
+
     // Current minimum supported version of serde_derive crate is Rust 1.56.
     if minor < 56 {
         println!("cargo:rustc-cfg=no_serde_derive");

serde/src/de/format.rs

@@ -1,5 +1,5 @@
-use lib::fmt::{self, Write};
-use lib::str;
+use crate::lib::fmt::{self, Write};
+use crate::lib::str;
 
 pub(super) struct Buf<'a> {
     bytes: &'a mut [u8],

serde/src/de/ignored_any.rs

@@ -1,6 +1,6 @@
-use lib::*;
+use crate::lib::*;
 
-use de::{
+use crate::de::{
     Deserialize, Deserializer, EnumAccess, Error, MapAccess, SeqAccess, VariantAccess, Visitor,
 };
 
@@ -197,7 +197,7 @@ impl<'de> Visitor<'de> for IgnoredAny {
     where
         A: SeqAccess<'de>,
     {
-        while let Some(IgnoredAny) = try!(seq.next_element()) {
+        while let Some(IgnoredAny) = tri!(seq.next_element()) {
             // Gobble
         }
         Ok(IgnoredAny)
@@ -208,7 +208,7 @@ impl<'de> Visitor<'de> for IgnoredAny {
     where
         A: MapAccess<'de>,
     {
-        while let Some((IgnoredAny, IgnoredAny)) = try!(map.next_entry()) {
+        while let Some((IgnoredAny, IgnoredAny)) = tri!(map.next_entry()) {
             // Gobble
         }
         Ok(IgnoredAny)
@@ -227,7 +227,7 @@ impl<'de> Visitor<'de> for IgnoredAny {
     where
         A: EnumAccess<'de>,
     {
-        try!(data.variant::<IgnoredAny>()).1.newtype_variant()
+        tri!(data.variant::<IgnoredAny>()).1.newtype_variant()
     }
 }
 

serde/src/de/impls.rs

@@ -1,16 +1,14 @@
-use lib::*;
+use crate::lib::*;
 
-use de::{
-    Deserialize, Deserializer, EnumAccess, Error, SeqAccess, Unexpected, VariantAccess, Visitor,
+use crate::de::{
+    Deserialize, Deserializer, EnumAccess, Error, MapAccess, SeqAccess, Unexpected, VariantAccess,
+    Visitor,
 };
 
-#[cfg(any(feature = "std", feature = "alloc", not(no_core_duration)))]
-use de::MapAccess;
-
-use seed::InPlaceSeed;
+use crate::seed::InPlaceSeed;
 
 #[cfg(any(feature = "std", feature = "alloc"))]
-use __private::size_hint;
+use crate::__private::size_hint;
 
 ////////////////////////////////////////////////////////////////////////////////
 
@@ -84,7 +82,7 @@ macro_rules! impl_deserialize_num {
     ($primitive:ident, $nonzero:ident $(cfg($($cfg:tt)*))*, $deserialize:ident $($method:ident!($($val:ident : $visit:ident)*);)*) => {
         impl_deserialize_num!($primitive, $deserialize $($method!($($val : $visit)*);)*);
 
-        #[cfg(all(not(no_num_nonzero), $($($cfg)*)*))]
+        $(#[cfg($($cfg)*)])*
         impl<'de> Deserialize<'de> for num::$nonzero {
             fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
             where
@@ -684,7 +682,7 @@ impl<'de> Visitor<'de> for CStringVisitor {
         let capacity = size_hint::cautious::<u8>(seq.size_hint());
         let mut values = Vec::<u8>::with_capacity(capacity);
 
-        while let Some(value) = try!(seq.next_element()) {
+        while let Some(value) = tri!(seq.next_element()) {
             values.push(value);
         }
 
@@ -747,13 +745,9 @@ macro_rules! forwarded_impl {
     }
 }
 
-#[cfg(all(
-    any(feature = "std", all(not(no_core_cstr), feature = "alloc")),
-    not(no_de_boxed_c_str)
-))]
+#[cfg(any(feature = "std", all(not(no_core_cstr), feature = "alloc")))]
 forwarded_impl!((), Box<CStr>, CString::into_boxed_c_str);
 
-#[cfg(not(no_core_reverse))]
 forwarded_impl!((T), Reverse<T>, Reverse);
 
 ////////////////////////////////////////////////////////////////////////////////
@@ -901,7 +895,7 @@ macro_rules! seq_impl {
                     {
                         let mut values = $with_capacity;
 
-                        while let Some(value) = try!($access.next_element()) {
+                        while let Some(value) = tri!($access.next_element()) {
                             $insert(&mut values, value);
                         }
 
@@ -939,7 +933,7 @@ macro_rules! seq_impl {
                         $reserve(&mut self.0, size_hint::cautious::<T>($access.size_hint()));
 
                         // FIXME: try to overwrite old values here? (Vec, VecDeque, LinkedList)
-                        while let Some(value) = try!($access.next_element()) {
+                        while let Some(value) = tri!($access.next_element()) {
                             $insert(&mut self.0, value);
                         }
 
@@ -1039,7 +1033,7 @@ where
                 let capacity = size_hint::cautious::<T>(seq.size_hint());
                 let mut values = Vec::<T>::with_capacity(capacity);
 
-                while let Some(value) = try!(seq.next_element()) {
+                while let Some(value) = tri!(seq.next_element()) {
                     values.push(value);
                 }
 
@@ -1081,7 +1075,7 @@ where
                 for i in 0..self.0.len() {
                     let next = {
                         let next_place = InPlaceSeed(&mut self.0[i]);
-                        try!(seq.next_element_seed(next_place))
+                        tri!(seq.next_element_seed(next_place))
                     };
                     if next.is_none() {
                         self.0.truncate(i);
@@ -1089,7 +1083,7 @@ where
                     }
                 }
 
-                while let Some(value) = try!(seq.next_element()) {
+                while let Some(value) = tri!(seq.next_element()) {
                     self.0.push(value);
                 }
 
@@ -1161,7 +1155,7 @@ macro_rules! array_impls {
                     A: SeqAccess<'de>,
                 {
                     Ok([$(
-                        match try!(seq.next_element()) {
+                        match tri!(seq.next_element()) {
                             Some(val) => val,
                             None => return Err(Error::invalid_length($n, &self)),
                         }
@@ -1186,7 +1180,7 @@ macro_rules! array_impls {
                 {
                     let mut fail_idx = None;
                     for (idx, dest) in self.0[..].iter_mut().enumerate() {
-                        if try!(seq.next_element_seed(InPlaceSeed(dest))).is_none() {
+                        if tri!(seq.next_element_seed(InPlaceSeed(dest))).is_none() {
                             fail_idx = Some(idx);
                             break;
                         }
@@ -1284,7 +1278,7 @@ macro_rules! tuple_impls {
                             A: SeqAccess<'de>,
                         {
                             $(
-                                let $name = match try!(seq.next_element()) {
+                                let $name = match tri!(seq.next_element()) {
                                     Some(value) => value,
                                     None => return Err(Error::invalid_length($n, &self)),
                                 };
@@ -1318,7 +1312,7 @@ macro_rules! tuple_impls {
                             A: SeqAccess<'de>,
                         {
                             $(
-                                if try!(seq.next_element_seed(InPlaceSeed(&mut (self.0).$n))).is_none() {
+                                if tri!(seq.next_element_seed(InPlaceSeed(&mut (self.0).$n))).is_none() {
                                     return Err(Error::invalid_length($n, &self));
                                 }
                             )+
@@ -1395,7 +1389,7 @@ macro_rules! map_impl {
                     {
                         let mut values = $with_capacity;
 
-                        while let Some((key, value)) = try!($access.next_entry()) {
+                        while let Some((key, value)) = tri!($access.next_entry()) {
                             values.insert(key, value);
                         }
 
@@ -1541,7 +1535,7 @@ macro_rules! deserialize_enum {
             where
                 A: EnumAccess<'de>,
             {
-                match try!(data.variant()) {
+                match tri!(data.variant()) {
                     $(
                         ($name_kind :: $variant, v) => v.newtype_variant().map($name :: $variant),
                     )*
@@ -1561,7 +1555,7 @@ impl<'de> Deserialize<'de> for net::IpAddr {
         if deserializer.is_human_readable() {
             deserializer.deserialize_str(FromStrVisitor::new("IP address"))
         } else {
-            use lib::net::IpAddr;
+            use crate::lib::net::IpAddr;
             deserialize_enum! {
                 IpAddr IpAddrKind (V4; b"V4"; 0, V6; b"V6"; 1)
                 "`V4` or `V6`",
@@ -1604,7 +1598,7 @@ impl<'de> Deserialize<'de> for net::SocketAddr {
         if deserializer.is_human_readable() {
             deserializer.deserialize_str(FromStrVisitor::new("socket address"))
         } else {
-            use lib::net::SocketAddr;
+            use crate::lib::net::SocketAddr;
             deserialize_enum! {
                 SocketAddr SocketAddrKind (V4; b"V4"; 0, V6; b"V6"; 1)
                 "`V4` or `V6`",
@@ -1714,7 +1708,7 @@ impl<'de> Deserialize<'de> for PathBuf {
     }
 }
 
-#[cfg(all(feature = "std", not(no_de_boxed_path)))]
+#[cfg(feature = "std")]
 forwarded_impl!((), Box<Path>, PathBuf::into_boxed_path);
 
 ////////////////////////////////////////////////////////////////////////////////
@@ -1748,7 +1742,7 @@ impl<'de> Visitor<'de> for OsStringVisitor {
     {
         use std::os::unix::ffi::OsStringExt;
 
-        match try!(data.variant()) {
+        match tri!(data.variant()) {
             (OsStringKind::Unix, v) => v.newtype_variant().map(OsString::from_vec),
             (OsStringKind::Windows, _) => Err(Error::custom(
                 "cannot deserialize Windows OS string on Unix",
@@ -1763,7 +1757,7 @@ impl<'de> Visitor<'de> for OsStringVisitor {
     {
         use std::os::windows::ffi::OsStringExt;
 
-        match try!(data.variant()) {
+        match tri!(data.variant()) {
             (OsStringKind::Windows, v) => v
                 .newtype_variant::<Vec<u16>>()
                 .map(|vec| OsString::from_wide(&vec)),
@@ -1795,30 +1789,6 @@ forwarded_impl!((T), Box<[T]>, Vec::into_boxed_slice);
 #[cfg(any(feature = "std", feature = "alloc"))]
 forwarded_impl!((), Box<str>, String::into_boxed_str);
 
-#[cfg(all(no_de_rc_dst, feature = "rc", any(feature = "std", feature = "alloc")))]
-forwarded_impl! {
-    /// This impl requires the [`"rc"`] Cargo feature of Serde.
-    ///
-    /// Deserializing a data structure containing `Arc` will not attempt to
-    /// deduplicate `Arc` references to the same data. Every deserialized `Arc`
-    /// will end up with a strong count of 1.
-    ///
-    /// [`"rc"`]: https://serde.rs/feature-flags.html#-features-rc
-    (T), Arc<T>, Arc::new
-}
-
-#[cfg(all(no_de_rc_dst, feature = "rc", any(feature = "std", feature = "alloc")))]
-forwarded_impl! {
-    /// This impl requires the [`"rc"`] Cargo feature of Serde.
-    ///
-    /// Deserializing a data structure containing `Rc` will not attempt to
-    /// deduplicate `Rc` references to the same data. Every deserialized `Rc`
-    /// will end up with a strong count of 1.
-    ///
-    /// [`"rc"`]: https://serde.rs/feature-flags.html#-features-rc
-    (T), Rc<T>, Rc::new
-}
-
 #[cfg(any(feature = "std", feature = "alloc"))]
 impl<'de, 'a, T: ?Sized> Deserialize<'de> for Cow<'a, T>
 where
@@ -1849,7 +1819,7 @@ where
     where
         D: Deserializer<'de>,
     {
-        try!(Option::<T>::deserialize(deserializer));
+        tri!(Option::<T>::deserialize(deserializer));
         Ok(RcWeak::new())
     }
 }
@@ -1867,18 +1837,14 @@ where
     where
         D: Deserializer<'de>,
     {
-        try!(Option::<T>::deserialize(deserializer));
+        tri!(Option::<T>::deserialize(deserializer));
         Ok(ArcWeak::new())
     }
 }
 
 ////////////////////////////////////////////////////////////////////////////////
 
-#[cfg(all(
-    not(no_de_rc_dst),
-    feature = "rc",
-    any(feature = "std", feature = "alloc")
-))]
+#[cfg(all(feature = "rc", any(feature = "std", feature = "alloc")))]
 macro_rules! box_forwarded_impl {
     (
         $(#[doc = $doc:tt])*
@@ -1899,11 +1865,7 @@ macro_rules! box_forwarded_impl {
     };
 }
 
-#[cfg(all(
-    not(no_de_rc_dst),
-    feature = "rc",
-    any(feature = "std", feature = "alloc")
-))]
+#[cfg(all(feature = "rc", any(feature = "std", feature = "alloc")))]
 box_forwarded_impl! {
     /// This impl requires the [`"rc"`] Cargo feature of Serde.
     ///
@@ -1915,11 +1877,7 @@ box_forwarded_impl! {
     Rc
 }
 
-#[cfg(all(
-    not(no_de_rc_dst),
-    feature = "rc",
-    any(feature = "std", feature = "alloc")
-))]
+#[cfg(all(feature = "rc", any(feature = "std", feature = "alloc")))]
 box_forwarded_impl! {
     /// This impl requires the [`"rc"`] Cargo feature of Serde.
     ///
@@ -1963,7 +1921,6 @@ forwarded_impl!((T), RwLock<T>, RwLock::new);
 //         secs: u64,
 //         nanos: u32,
 //     }
-#[cfg(any(feature = "std", not(no_core_duration)))]
 impl<'de> Deserialize<'de> for Duration {
     fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
     where
@@ -2011,7 +1968,7 @@ impl<'de> Deserialize<'de> for Duration {
                             b"secs" => Ok(Field::Secs),
                             b"nanos" => Ok(Field::Nanos),
                             _ => {
-                                let value = ::__private::from_utf8_lossy(value);
+                                let value = crate::__private::from_utf8_lossy(value);
                                 Err(Error::unknown_field(&*value, FIELDS))
                             }
                         }
@@ -2046,19 +2003,19 @@ impl<'de> Deserialize<'de> for Duration {
             where
                 A: SeqAccess<'de>,
             {
-                let secs: u64 = match try!(seq.next_element()) {
+                let secs: u64 = match tri!(seq.next_element()) {
                     Some(value) => value,
                     None => {
                         return Err(Error::invalid_length(0, &self));
                     }
                 };
-                let nanos: u32 = match try!(seq.next_element()) {
+                let nanos: u32 = match tri!(seq.next_element()) {
                     Some(value) => value,
                     None => {
                         return Err(Error::invalid_length(1, &self));
                     }
                 };
-                try!(check_overflow(secs, nanos));
+                tri!(check_overflow(secs, nanos));
                 Ok(Duration::new(secs, nanos))
             }
 
@@ -2068,19 +2025,19 @@ impl<'de> Deserialize<'de> for Duration {
             {
                 let mut secs: Option<u64> = None;
                 let mut nanos: Option<u32> = None;
-                while let Some(key) = try!(map.next_key()) {
+                while let Some(key) = tri!(map.next_key()) {
                     match key {
                         Field::Secs => {
                             if secs.is_some() {
                                 return Err(<A::Error as Error>::duplicate_field("secs"));
                             }
-                            secs = Some(try!(map.next_value()));
+                            secs = Some(tri!(map.next_value()));
                         }
                         Field::Nanos => {
                             if nanos.is_some() {
                                 return Err(<A::Error as Error>::duplicate_field("nanos"));
                             }
-                            nanos = Some(try!(map.next_value()));
+                            nanos = Some(tri!(map.next_value()));
                         }
                     }
                 }
@@ -2092,7 +2049,7 @@ impl<'de> Deserialize<'de> for Duration {
                     Some(nanos) => nanos,
                     None => return Err(<A::Error as Error>::missing_field("nanos")),
                 };
-                try!(check_overflow(secs, nanos));
+                tri!(check_overflow(secs, nanos));
                 Ok(Duration::new(secs, nanos))
             }
         }
@@ -2184,19 +2141,19 @@ impl<'de> Deserialize<'de> for SystemTime {
             where
                 A: SeqAccess<'de>,
             {
-                let secs: u64 = match try!(seq.next_element()) {
+                let secs: u64 = match tri!(seq.next_element()) {
                     Some(value) => value,
                     None => {
                         return Err(Error::invalid_length(0, &self));
                     }
                 };
-                let nanos: u32 = match try!(seq.next_element()) {
+                let nanos: u32 = match tri!(seq.next_element()) {
                     Some(value) => value,
                     None => {
                         return Err(Error::invalid_length(1, &self));
                     }
                 };
-                try!(check_overflow(secs, nanos));
+                tri!(check_overflow(secs, nanos));
                 Ok(Duration::new(secs, nanos))
             }
 
@@ -2206,7 +2163,7 @@ impl<'de> Deserialize<'de> for SystemTime {
             {
                 let mut secs: Option<u64> = None;
                 let mut nanos: Option<u32> = None;
-                while let Some(key) = try!(map.next_key()) {
+                while let Some(key) = tri!(map.next_key()) {
                     match key {
                         Field::Secs => {
                             if secs.is_some() {
@@ -2214,7 +2171,7 @@ impl<'de> Deserialize<'de> for SystemTime {
                                     "secs_since_epoch",
                                 ));
                             }
-                            secs = Some(try!(map.next_value()));
+                            secs = Some(tri!(map.next_value()));
                         }
                         Field::Nanos => {
                             if nanos.is_some() {
@@ -2222,7 +2179,7 @@ impl<'de> Deserialize<'de> for SystemTime {
                                     "nanos_since_epoch",
                                 ));
                             }
-                            nanos = Some(try!(map.next_value()));
+                            nanos = Some(tri!(map.next_value()));
                         }
                     }
                 }
@@ -2234,13 +2191,13 @@ impl<'de> Deserialize<'de> for SystemTime {
                     Some(nanos) => nanos,
                     None => return Err(<A::Error as Error>::missing_field("nanos_since_epoch")),
                 };
-                try!(check_overflow(secs, nanos));
+                tri!(check_overflow(secs, nanos));
                 Ok(Duration::new(secs, nanos))
             }
         }
 
         const FIELDS: &[&str] = &["secs_since_epoch", "nanos_since_epoch"];
-        let duration = try!(deserializer.deserialize_struct("SystemTime", FIELDS, DurationVisitor));
+        let duration = tri!(deserializer.deserialize_struct("SystemTime", FIELDS, DurationVisitor));
         #[cfg(not(no_systemtime_checked_add))]
         let ret = UNIX_EPOCH
             .checked_add(duration)
@@ -2269,7 +2226,7 @@ where
     where
         D: Deserializer<'de>,
     {
-        let (start, end) = try!(deserializer.deserialize_struct(
+        let (start, end) = tri!(deserializer.deserialize_struct(
             "Range",
             range::FIELDS,
             range::RangeVisitor {
@@ -2281,7 +2238,6 @@ where
     }
 }
 
-#[cfg(not(no_range_inclusive))]
 impl<'de, Idx> Deserialize<'de> for RangeInclusive<Idx>
 where
     Idx: Deserialize<'de>,
@@ -2290,7 +2246,7 @@ where
     where
         D: Deserializer<'de>,
     {
-        let (start, end) = try!(deserializer.deserialize_struct(
+        let (start, end) = tri!(deserializer.deserialize_struct(
             "RangeInclusive",
             range::FIELDS,
             range::RangeVisitor {
@@ -2303,9 +2259,9 @@ where
 }
 
 mod range {
-    use lib::*;
+    use crate::lib::*;
 
-    use de::{Deserialize, Deserializer, Error, MapAccess, SeqAccess, Visitor};
+    use crate::de::{Deserialize, Deserializer, Error, MapAccess, SeqAccess, Visitor};
 
     pub const FIELDS: &[&str] = &["start", "end"];
 
@@ -2351,7 +2307,7 @@ mod range {
                         b"start" => Ok(Field::Start),
                         b"end" => Ok(Field::End),
                         _ => {
-                            let value = ::__private::from_utf8_lossy(value);
+                            let value = crate::__private::from_utf8_lossy(value);
                             Err(Error::unknown_field(&*value, FIELDS))
                         }
                     }
@@ -2381,13 +2337,13 @@ mod range {
         where
             A: SeqAccess<'de>,
         {
-            let start: Idx = match try!(seq.next_element()) {
+            let start: Idx = match tri!(seq.next_element()) {
                 Some(value) => value,
                 None => {
                     return Err(Error::invalid_length(0, &self));
                 }
             };
-            let end: Idx = match try!(seq.next_element()) {
+            let end: Idx = match tri!(seq.next_element()) {
                 Some(value) => value,
                 None => {
                     return Err(Error::invalid_length(1, &self));
@@ -2402,19 +2358,19 @@ mod range {
         {
             let mut start: Option<Idx> = None;
             let mut end: Option<Idx> = None;
-            while let Some(key) = try!(map.next_key()) {
+            while let Some(key) = tri!(map.next_key()) {
                 match key {
                     Field::Start => {
                         if start.is_some() {
                             return Err(<A::Error as Error>::duplicate_field("start"));
                         }
-                        start = Some(try!(map.next_value()));
+                        start = Some(tri!(map.next_value()));
                     }
                     Field::End => {
                         if end.is_some() {
                             return Err(<A::Error as Error>::duplicate_field("end"));
                         }
-                        end = Some(try!(map.next_value()));
+                        end = Some(tri!(map.next_value()));
                     }
                 }
             }
@@ -2448,7 +2404,7 @@ where
     where
         D: Deserializer<'de>,
     {
-        let start = try!(deserializer.deserialize_struct(
+        let start = tri!(deserializer.deserialize_struct(
             "RangeFrom",
             range_from::FIELDS,
             range_from::RangeFromVisitor {
@@ -2461,9 +2417,9 @@ where
 }
 
 mod range_from {
-    use lib::*;
+    use crate::lib::*;
 
-    use de::{Deserialize, Deserializer, Error, MapAccess, SeqAccess, Visitor};
+    use crate::de::{Deserialize, Deserializer, Error, MapAccess, SeqAccess, Visitor};
 
     pub const FIELDS: &[&str] = &["end"];
 
@@ -2506,7 +2462,7 @@ mod range_from {
                     match value {
                         b"end" => Ok(Field::End),
                         _ => {
-                            let value = ::__private::from_utf8_lossy(value);
+                            let value = crate::__private::from_utf8_lossy(value);
                             Err(Error::unknown_field(&*value, FIELDS))
                         }
                     }
@@ -2536,7 +2492,7 @@ mod range_from {
         where
             A: SeqAccess<'de>,
         {
-            let end: Idx = match try!(seq.next_element()) {
+            let end: Idx = match tri!(seq.next_element()) {
                 Some(value) => value,
                 None => {
                     return Err(Error::invalid_length(0, &self));
@@ -2550,13 +2506,13 @@ mod range_from {
             A: MapAccess<'de>,
         {
             let mut end: Option<Idx> = None;
-            while let Some(key) = try!(map.next_key()) {
+            while let Some(key) = tri!(map.next_key()) {
                 match key {
                     Field::End => {
                         if end.is_some() {
                             return Err(<A::Error as Error>::duplicate_field("end"));
                         }
-                        end = Some(try!(map.next_value()));
+                        end = Some(tri!(map.next_value()));
                     }
                 }
             }
@@ -2586,7 +2542,7 @@ where
     where
         D: Deserializer<'de>,
     {
-        let end = try!(deserializer.deserialize_struct(
+        let end = tri!(deserializer.deserialize_struct(
             "RangeTo",
             range_to::FIELDS,
             range_to::RangeToVisitor {
@@ -2599,9 +2555,9 @@ where
 }
 
 mod range_to {
-    use lib::*;
+    use crate::lib::*;
 
-    use de::{Deserialize, Deserializer, Error, MapAccess, SeqAccess, Visitor};
+    use crate::de::{Deserialize, Deserializer, Error, MapAccess, SeqAccess, Visitor};
 
     pub const FIELDS: &[&str] = &["start"];
 
@@ -2644,7 +2600,7 @@ mod range_to {
                     match value {
                         b"start" => Ok(Field::Start),
                         _ => {
-                            let value = ::__private::from_utf8_lossy(value);
+                            let value = crate::__private::from_utf8_lossy(value);
                             Err(Error::unknown_field(&*value, FIELDS))
                         }
                     }
@@ -2674,7 +2630,7 @@ mod range_to {
         where
             A: SeqAccess<'de>,
         {
-            let start: Idx = match try!(seq.next_element()) {
+            let start: Idx = match tri!(seq.next_element()) {
                 Some(value) => value,
                 None => {
                     return Err(Error::invalid_length(0, &self));
@@ -2688,13 +2644,13 @@ mod range_to {
             A: MapAccess<'de>,
         {
             let mut start: Option<Idx> = None;
-            while let Some(key) = try!(map.next_key()) {
+            while let Some(key) = tri!(map.next_key()) {
                 match key {
                     Field::Start => {
                         if start.is_some() {
                             return Err(<A::Error as Error>::duplicate_field("start"));
                         }
-                        start = Some(try!(map.next_value()));
+                        start = Some(tri!(map.next_value()));
                     }
                 }
             }
@@ -2709,7 +2665,6 @@ mod range_to {
 
 ////////////////////////////////////////////////////////////////////////////////
 
-#[cfg(any(not(no_ops_bound), all(feature = "std", not(no_collections_bound))))]
 impl<'de, T> Deserialize<'de> for Bound<T>
 where
     T: Deserialize<'de>,
@@ -2801,7 +2756,7 @@ where
             where
                 A: EnumAccess<'de>,
             {
-                match try!(data.variant()) {
+                match tri!(data.variant()) {
                     (Field::Unbounded, v) => v.unit_variant().map(|()| Bound::Unbounded),
                     (Field::Included, v) => v.newtype_variant().map(Bound::Included),
                     (Field::Excluded, v) => v.newtype_variant().map(Bound::Excluded),
@@ -2910,7 +2865,7 @@ where
             where
                 A: EnumAccess<'de>,
             {
-                match try!(data.variant()) {
+                match tri!(data.variant()) {
                     (Field::Ok, v) => v.newtype_variant().map(Ok),
                     (Field::Err, v) => v.newtype_variant().map(Err),
                 }

serde/src/de/mod.rs

@@ -112,7 +112,7 @@
 //! [derive section of the manual]: https://serde.rs/derive.html
 //! [data formats]: https://serde.rs/#data-formats
 
-use lib::*;
+use crate::lib::*;
 
 ////////////////////////////////////////////////////////////////////////////////
 
@@ -126,12 +126,15 @@ mod utf8;
 
 pub use self::ignored_any::IgnoredAny;
 
+#[cfg(not(any(feature = "std", feature = "unstable")))]
+#[doc(no_inline)]
+pub use crate::std_error::Error as StdError;
+#[cfg(all(feature = "unstable", not(feature = "std")))]
+#[doc(no_inline)]
+pub use core::error::Error as StdError;
 #[cfg(feature = "std")]
 #[doc(no_inline)]
 pub use std::error::Error as StdError;
-#[cfg(not(feature = "std"))]
-#[doc(no_inline)]
-pub use std_error::Error as StdError;
 
 ////////////////////////////////////////////////////////////////////////////////
 
@@ -566,7 +569,7 @@ pub trait Deserialize<'de>: Sized {
         D: Deserializer<'de>,
     {
         // Default implementation just delegates to `deserialize` impl.
-        *place = try!(Deserialize::deserialize(deserializer));
+        *place = tri!(Deserialize::deserialize(deserializer));
         Ok(())
     }
 }
@@ -1226,11 +1229,11 @@ pub trait Deserializer<'de>: Sized {
     #[doc(hidden)]
     fn __deserialize_content<V>(
         self,
-        _: ::actually_private::T,
+        _: crate::actually_private::T,
         visitor: V,
-    ) -> Result<::private::de::Content<'de>, Self::Error>
+    ) -> Result<crate::__private::de::Content<'de>, Self::Error>
     where
-        V: Visitor<'de, Value = ::private::de::Content<'de>>,
+        V: Visitor<'de, Value = crate::__private::de::Content<'de>>,
     {
         self.deserialize_any(visitor)
     }
@@ -1831,9 +1834,9 @@ pub trait MapAccess<'de> {
         K: DeserializeSeed<'de>,
         V: DeserializeSeed<'de>,
     {
-        match try!(self.next_key_seed(kseed)) {
+        match tri!(self.next_key_seed(kseed)) {
             Some(key) => {
-                let value = try!(self.next_value_seed(vseed));
+                let value = tri!(self.next_value_seed(vseed));
                 Ok(Some((key, value)))
             }
             None => Ok(None),
@@ -2281,12 +2284,12 @@ impl Display for OneOf {
             1 => write!(formatter, "`{}`", self.names[0]),
             2 => write!(formatter, "`{}` or `{}`", self.names[0], self.names[1]),
             _ => {
-                try!(write!(formatter, "one of "));
+                tri!(write!(formatter, "one of "));
                 for (i, alt) in self.names.iter().enumerate() {
                     if i > 0 {
-                        try!(write!(formatter, ", "));
+                        tri!(write!(formatter, ", "));
                     }
-                    try!(write!(formatter, "`{}`", alt));
+                    tri!(write!(formatter, "`{}`", alt));
                 }
                 Ok(())
             }

serde/src/de/seed.rs

@@ -1,4 +1,4 @@
-use de::{Deserialize, DeserializeSeed, Deserializer};
+use crate::de::{Deserialize, DeserializeSeed, Deserializer};
 
 /// A DeserializeSeed helper for implementing deserialize_in_place Visitors.
 ///

serde/src/de/utf8.rs

@@ -1,4 +1,4 @@
-use lib::*;
+use crate::lib::*;
 
 const TAG_CONT: u8 = 0b1000_0000;
 const TAG_TWO_B: u8 = 0b1100_0000;

serde/src/de/value.rs

@@ -21,12 +21,12 @@
 //! }
 //! ```
 
-use lib::*;
+use crate::lib::*;
 
 use self::private::{First, Second};
-use __private::size_hint;
-use de::{self, Deserializer, Expected, IntoDeserializer, SeqAccess, Visitor};
-use ser;
+use crate::__private::size_hint;
+use crate::de::{self, Deserializer, Expected, IntoDeserializer, SeqAccess, Visitor};
+use crate::ser;
 
 ////////////////////////////////////////////////////////////////////////////////
 
@@ -937,8 +937,8 @@ where
     where
         V: de::Visitor<'de>,
     {
-        let v = try!(visitor.visit_seq(&mut self));
-        try!(self.end());
+        let v = tri!(visitor.visit_seq(&mut self));
+        tri!(self.end());
         Ok(v)
     }
 
@@ -1162,8 +1162,8 @@ where
     where
         V: de::Visitor<'de>,
     {
-        let value = try!(visitor.visit_map(&mut self));
-        try!(self.end());
+        let value = tri!(visitor.visit_map(&mut self));
+        tri!(self.end());
         Ok(value)
     }
 
@@ -1171,8 +1171,8 @@ where
     where
         V: de::Visitor<'de>,
     {
-        let value = try!(visitor.visit_seq(&mut self));
-        try!(self.end());
+        let value = tri!(visitor.visit_seq(&mut self));
+        tri!(self.end());
         Ok(value)
     }
 
@@ -1236,8 +1236,8 @@ where
     {
         match self.next_pair() {
             Some((key, value)) => {
-                let key = try!(kseed.deserialize(key.into_deserializer()));
-                let value = try!(vseed.deserialize(value.into_deserializer()));
+                let key = tri!(kseed.deserialize(key.into_deserializer()));
+                let value = tri!(vseed.deserialize(value.into_deserializer()));
                 Ok(Some((key, value)))
             }
             None => Ok(None),
@@ -1341,7 +1341,7 @@ where
         V: de::Visitor<'de>,
     {
         let mut pair_visitor = PairVisitor(Some(self.0), Some(self.1), PhantomData);
-        let pair = try!(visitor.visit_seq(&mut pair_visitor));
+        let pair = tri!(visitor.visit_seq(&mut pair_visitor));
         if pair_visitor.1.is_none() {
             Ok(pair)
         } else {
@@ -1501,7 +1501,7 @@ where
     where
         T: de::DeserializeSeed<'de>,
     {
-        match try!(self.map.next_key_seed(seed)) {
+        match tri!(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")),
         }
@@ -1546,9 +1546,11 @@ where
 ////////////////////////////////////////////////////////////////////////////////
 
 mod private {
-    use lib::*;
+    use crate::lib::*;
 
-    use de::{self, DeserializeSeed, Deserializer, MapAccess, Unexpected, VariantAccess, Visitor};
+    use crate::de::{
+        self, DeserializeSeed, Deserializer, MapAccess, Unexpected, VariantAccess, Visitor,
+    };
 
     pub struct UnitOnly<E> {
         marker: PhantomData<E>,

serde/src/lib.rs

@@ -93,7 +93,7 @@
 ////////////////////////////////////////////////////////////////////////////////
 
 // Serde types in rustdoc of other crates get linked to here.
-#![doc(html_root_url = "https://docs.rs/serde/1.0.176")]
+#![doc(html_root_url = "https://docs.rs/serde/1.0.180")]
 // 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
@@ -149,6 +149,8 @@
         must_use_candidate,
     )
 )]
+// Restrictions
+#![cfg_attr(feature = "cargo-clippy", deny(question_mark_used))]
 // Rustc lints.
 #![deny(missing_docs, unused_imports)]
 
@@ -175,14 +177,16 @@ mod lib {
 
     pub use self::core::cell::{Cell, RefCell};
     pub use self::core::clone::{self, Clone};
+    pub use self::core::cmp::Reverse;
     pub use self::core::convert::{self, From, Into};
     pub use self::core::default::{self, Default};
     pub use self::core::fmt::{self, Debug, Display};
     pub use self::core::marker::{self, PhantomData};
     pub use self::core::num::Wrapping;
-    pub use self::core::ops::{Range, RangeFrom, RangeTo};
+    pub use self::core::ops::{Bound, Range, RangeFrom, RangeInclusive, RangeTo};
     pub use self::core::option::{self, Option};
     pub use self::core::result::{self, Result};
+    pub use self::core::time::Duration;
 
     #[cfg(all(feature = "alloc", not(feature = "std")))]
     pub use alloc::borrow::{Cow, ToOwned};
@@ -220,7 +224,7 @@ mod lib {
     pub use std::collections::{BTreeMap, BTreeSet, BinaryHeap, LinkedList, VecDeque};
 
     #[cfg(all(not(no_core_cstr), not(feature = "std")))]
-    pub use core::ffi::CStr;
+    pub use self::core::ffi::CStr;
     #[cfg(feature = "std")]
     pub use std::ffi::CStr;
 
@@ -247,18 +251,6 @@ mod lib {
     #[cfg(feature = "std")]
     pub use std::time::{SystemTime, UNIX_EPOCH};
 
-    #[cfg(all(feature = "std", not(no_collections_bound), no_ops_bound))]
-    pub use std::collections::Bound;
-
-    #[cfg(not(no_core_reverse))]
-    pub use self::core::cmp::Reverse;
-
-    #[cfg(not(no_ops_bound))]
-    pub use self::core::ops::Bound;
-
-    #[cfg(not(no_range_inclusive))]
-    pub use self::core::ops::RangeInclusive;
-
     #[cfg(all(feature = "std", no_target_has_atomic, not(no_std_atomic)))]
     pub use std::sync::atomic::{
         AtomicBool, AtomicI16, AtomicI32, AtomicI8, AtomicIsize, AtomicU16, AtomicU32, AtomicU8,
@@ -279,16 +271,13 @@ mod lib {
     pub use std::sync::atomic::{AtomicI64, AtomicU64};
     #[cfg(all(feature = "std", not(no_target_has_atomic), target_has_atomic = "ptr"))]
     pub use std::sync::atomic::{AtomicIsize, AtomicUsize};
-
-    #[cfg(any(feature = "std", not(no_core_duration)))]
-    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 {
+macro_rules! tri {
     ($expr:expr) => {
         match $expr {
             Ok(val) => val,
@@ -309,20 +298,15 @@ pub mod de;
 pub mod ser;
 
 #[doc(inline)]
-pub use de::{Deserialize, Deserializer};
+pub use crate::de::{Deserialize, Deserializer};
 #[doc(inline)]
-pub use ser::{Serialize, Serializer};
+pub use crate::ser::{Serialize, Serializer};
 
 // Used by generated code and doc tests. Not public API.
 #[doc(hidden)]
 #[path = "private/mod.rs"]
 pub mod __private;
 
-#[allow(unused_imports)]
-use self::__private as export;
-#[allow(unused_imports)]
-use self::__private as private;
-
 #[path = "de/seed.rs"]
 mod seed;
 

serde/src/private/de.rs

@@ -1,10 +1,10 @@
-use lib::*;
+use crate::lib::*;
 
-use de::value::{BorrowedBytesDeserializer, BytesDeserializer};
-use de::{Deserialize, Deserializer, Error, IntoDeserializer, Visitor};
+use crate::de::value::{BorrowedBytesDeserializer, BytesDeserializer};
+use crate::de::{Deserialize, Deserializer, Error, IntoDeserializer, Visitor};
 
 #[cfg(any(feature = "std", feature = "alloc"))]
-use de::{DeserializeSeed, MapAccess, Unexpected};
+use crate::de::{DeserializeSeed, MapAccess, Unexpected};
 
 #[cfg(any(feature = "std", feature = "alloc"))]
 pub use self::content::{
@@ -13,7 +13,7 @@ pub use self::content::{
     TagOrContentField, TagOrContentFieldVisitor, TaggedContentVisitor, UntaggedUnitVisitor,
 };
 
-pub use seed::InPlaceSeed;
+pub use crate::seed::InPlaceSeed;
 
 /// If the missing field is of type `Option<T>` then treat is as `None`,
 /// otherwise it is an error.
@@ -203,11 +203,12 @@ mod content {
     // This issue is tracking making some of this stuff public:
     // https://github.com/serde-rs/serde/issues/741
 
-    use lib::*;
+    use crate::lib::*;
 
-    use __private::size_hint;
-    use actually_private;
-    use de::{
+    use crate::__private::size_hint;
+    use crate::actually_private;
+    use crate::de::value::{MapDeserializer, SeqDeserializer};
+    use crate::de::{
         self, Deserialize, DeserializeSeed, Deserializer, EnumAccess, Expected, IgnoredAny,
         MapAccess, SeqAccess, Unexpected, Visitor,
     };
@@ -299,6 +300,17 @@ mod content {
         }
     }
 
+    impl<'de, E> de::IntoDeserializer<'de, E> for Content<'de>
+    where
+        E: de::Error,
+    {
+        type Deserializer = ContentDeserializer<'de, E>;
+
+        fn into_deserializer(self) -> Self::Deserializer {
+            ContentDeserializer::new(self)
+        }
+    }
+
     struct ContentVisitor<'de> {
         value: PhantomData<Content<'de>>,
     }
@@ -476,7 +488,7 @@ mod content {
         {
             let mut vec =
                 Vec::<Content>::with_capacity(size_hint::cautious::<Content>(visitor.size_hint()));
-            while let Some(e) = try!(visitor.next_element()) {
+            while let Some(e) = tri!(visitor.next_element()) {
                 vec.push(e);
             }
             Ok(Content::Seq(vec))
@@ -490,7 +502,7 @@ mod content {
                 Vec::<(Content, Content)>::with_capacity(
                     size_hint::cautious::<(Content, Content)>(visitor.size_hint()),
                 );
-            while let Some(kv) = try!(visitor.next_entry()) {
+            while let Some(kv) = tri!(visitor.next_entry()) {
                 vec.push(kv);
             }
             Ok(Content::Map(vec))
@@ -833,14 +845,14 @@ mod content {
         where
             S: SeqAccess<'de>,
         {
-            let tag = match try!(seq.next_element()) {
+            let tag = match tri!(seq.next_element()) {
                 Some(tag) => tag,
                 None => {
                     return Err(de::Error::missing_field(self.tag_name));
                 }
             };
             let rest = de::value::SeqAccessDeserializer::new(seq);
-            Ok((tag, try!(Content::deserialize(rest))))
+            Ok((tag, tri!(Content::deserialize(rest))))
         }
 
         fn visit_map<M>(self, mut map: M) -> Result<Self::Value, M::Error>
@@ -852,16 +864,16 @@ mod content {
                 Content,
                 Content,
             )>(map.size_hint()));
-            while let Some(k) = try!(map.next_key_seed(TagOrContentVisitor::new(self.tag_name))) {
+            while let Some(k) = tri!(map.next_key_seed(TagOrContentVisitor::new(self.tag_name))) {
                 match k {
                     TagOrContent::Tag => {
                         if tag.is_some() {
                             return Err(de::Error::duplicate_field(self.tag_name));
                         }
-                        tag = Some(try!(map.next_value()));
+                        tag = Some(tri!(map.next_value()));
                     }
                     TagOrContent::Content(k) => {
-                        let v = try!(map.next_value());
+                        let v = tri!(map.next_value());
                         vec.push((k, v));
                     }
                 }
@@ -1074,9 +1086,9 @@ mod content {
         E: de::Error,
     {
         let seq = content.into_iter().map(ContentDeserializer::new);
-        let mut seq_visitor = de::value::SeqDeserializer::new(seq);
-        let value = try!(visitor.visit_seq(&mut seq_visitor));
-        try!(seq_visitor.end());
+        let mut seq_visitor = SeqDeserializer::new(seq);
+        let value = tri!(visitor.visit_seq(&mut seq_visitor));
+        tri!(seq_visitor.end());
         Ok(value)
     }
 
@@ -1091,9 +1103,9 @@ mod content {
         let map = content
             .into_iter()
             .map(|(k, v)| (ContentDeserializer::new(k), ContentDeserializer::new(v)));
-        let mut map_visitor = de::value::MapDeserializer::new(map);
-        let value = try!(visitor.visit_map(&mut map_visitor));
-        try!(map_visitor.end());
+        let mut map_visitor = MapDeserializer::new(map);
+        let value = tri!(visitor.visit_map(&mut map_visitor));
+        tri!(map_visitor.end());
         Ok(value)
     }
 
@@ -1569,7 +1581,7 @@ mod content {
         {
             match self.value {
                 Some(Content::Seq(v)) => {
-                    de::Deserializer::deserialize_any(SeqDeserializer::new(v), visitor)
+                    de::Deserializer::deserialize_any(SeqDeserializer::new(v.into_iter()), visitor)
                 }
                 Some(other) => Err(de::Error::invalid_type(
                     other.unexpected(),
@@ -1592,10 +1604,10 @@ mod content {
         {
             match self.value {
                 Some(Content::Map(v)) => {
-                    de::Deserializer::deserialize_any(MapDeserializer::new(v), visitor)
+                    de::Deserializer::deserialize_any(MapDeserializer::new(v.into_iter()), visitor)
                 }
                 Some(Content::Seq(v)) => {
-                    de::Deserializer::deserialize_any(SeqDeserializer::new(v), visitor)
+                    de::Deserializer::deserialize_any(SeqDeserializer::new(v.into_iter()), visitor)
                 }
                 Some(other) => Err(de::Error::invalid_type(
                     other.unexpected(),
@@ -1609,156 +1621,6 @@ mod content {
         }
     }
 
-    struct SeqDeserializer<'de, E>
-    where
-        E: de::Error,
-    {
-        iter: <Vec<Content<'de>> as IntoIterator>::IntoIter,
-        err: PhantomData<E>,
-    }
-
-    impl<'de, E> SeqDeserializer<'de, E>
-    where
-        E: de::Error,
-    {
-        fn new(vec: Vec<Content<'de>>) -> Self {
-            SeqDeserializer {
-                iter: vec.into_iter(),
-                err: PhantomData,
-            }
-        }
-    }
-
-    impl<'de, E> de::Deserializer<'de> for SeqDeserializer<'de, E>
-    where
-        E: de::Error,
-    {
-        type Error = E;
-
-        #[inline]
-        fn deserialize_any<V>(mut self, visitor: V) -> Result<V::Value, Self::Error>
-        where
-            V: de::Visitor<'de>,
-        {
-            let len = self.iter.len();
-            if len == 0 {
-                visitor.visit_unit()
-            } else {
-                let ret = try!(visitor.visit_seq(&mut self));
-                let remaining = self.iter.len();
-                if remaining == 0 {
-                    Ok(ret)
-                } else {
-                    Err(de::Error::invalid_length(len, &"fewer elements in array"))
-                }
-            }
-        }
-
-        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
-        }
-    }
-
-    impl<'de, E> de::SeqAccess<'de> for SeqDeserializer<'de, E>
-    where
-        E: de::Error,
-    {
-        type Error = E;
-
-        fn next_element_seed<T>(&mut self, seed: T) -> Result<Option<T::Value>, Self::Error>
-        where
-            T: de::DeserializeSeed<'de>,
-        {
-            match self.iter.next() {
-                Some(value) => seed.deserialize(ContentDeserializer::new(value)).map(Some),
-                None => Ok(None),
-            }
-        }
-
-        fn size_hint(&self) -> Option<usize> {
-            size_hint::from_bounds(&self.iter)
-        }
-    }
-
-    struct MapDeserializer<'de, E>
-    where
-        E: de::Error,
-    {
-        iter: <Vec<(Content<'de>, Content<'de>)> as IntoIterator>::IntoIter,
-        value: Option<Content<'de>>,
-        err: PhantomData<E>,
-    }
-
-    impl<'de, E> MapDeserializer<'de, E>
-    where
-        E: de::Error,
-    {
-        fn new(map: Vec<(Content<'de>, Content<'de>)>) -> Self {
-            MapDeserializer {
-                iter: map.into_iter(),
-                value: None,
-                err: PhantomData,
-            }
-        }
-    }
-
-    impl<'de, E> de::MapAccess<'de> for MapDeserializer<'de, E>
-    where
-        E: de::Error,
-    {
-        type Error = E;
-
-        fn next_key_seed<T>(&mut self, seed: T) -> Result<Option<T::Value>, Self::Error>
-        where
-            T: de::DeserializeSeed<'de>,
-        {
-            match self.iter.next() {
-                Some((key, value)) => {
-                    self.value = Some(value);
-                    seed.deserialize(ContentDeserializer::new(key)).map(Some)
-                }
-                None => Ok(None),
-            }
-        }
-
-        fn next_value_seed<T>(&mut self, seed: T) -> Result<T::Value, Self::Error>
-        where
-            T: de::DeserializeSeed<'de>,
-        {
-            match self.value.take() {
-                Some(value) => seed.deserialize(ContentDeserializer::new(value)),
-                None => Err(de::Error::custom("value is missing")),
-            }
-        }
-
-        fn size_hint(&self) -> Option<usize> {
-            size_hint::from_bounds(&self.iter)
-        }
-    }
-
-    impl<'de, E> de::Deserializer<'de> for MapDeserializer<'de, E>
-    where
-        E: de::Error,
-    {
-        type Error = E;
-
-        #[inline]
-        fn deserialize_any<V>(self, visitor: V) -> Result<V::Value, Self::Error>
-        where
-            V: de::Visitor<'de>,
-        {
-            visitor.visit_map(self)
-        }
-
-        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
-        }
-    }
-
     /// Not public API.
     pub struct ContentRefDeserializer<'a, 'de: 'a, E> {
         content: &'a Content<'de>,
@@ -1820,9 +1682,9 @@ mod content {
         E: de::Error,
     {
         let seq = content.iter().map(ContentRefDeserializer::new);
-        let mut seq_visitor = de::value::SeqDeserializer::new(seq);
-        let value = try!(visitor.visit_seq(&mut seq_visitor));
-        try!(seq_visitor.end());
+        let mut seq_visitor = SeqDeserializer::new(seq);
+        let value = tri!(visitor.visit_seq(&mut seq_visitor));
+        tri!(seq_visitor.end());
         Ok(value)
     }
 
@@ -1840,9 +1702,9 @@ mod content {
                 ContentRefDeserializer::new(v),
             )
         });
-        let mut map_visitor = de::value::MapDeserializer::new(map);
-        let value = try!(visitor.visit_map(&mut map_visitor));
-        try!(map_visitor.end());
+        let mut map_visitor = MapDeserializer::new(map);
+        let value = tri!(visitor.visit_map(&mut map_visitor));
+        tri!(map_visitor.end());
         Ok(value)
     }
 
@@ -2362,7 +2224,7 @@ mod content {
             if len == 0 {
                 visitor.visit_unit()
             } else {
-                let ret = try!(visitor.visit_seq(&mut self));
+                let ret = tri!(visitor.visit_seq(&mut self));
                 let remaining = self.iter.len();
                 if remaining == 0 {
                     Ok(ret)
@@ -2541,7 +2403,7 @@ mod content {
         where
             M: MapAccess<'de>,
         {
-            while try!(access.next_entry::<IgnoredAny, IgnoredAny>()).is_some() {}
+            while tri!(access.next_entry::<IgnoredAny, IgnoredAny>()).is_some() {}
             Ok(())
         }
     }

serde/src/private/doc.rs

@@ -1,8 +1,8 @@
 // Used only by Serde doc tests. Not public API.
 
-use lib::*;
+use crate::lib::*;
 
-use ser;
+use crate::ser;
 
 #[doc(hidden)]
 #[derive(Debug)]

serde/src/private/mod.rs

@@ -8,25 +8,25 @@ pub mod size_hint;
 // FIXME: #[cfg(doctest)] once https://github.com/rust-lang/rust/issues/67295 is fixed.
 pub mod doc;
 
-pub use lib::clone::Clone;
-pub use lib::convert::{From, Into};
-pub use lib::default::Default;
-pub use lib::fmt::{self, Formatter};
-pub use lib::marker::PhantomData;
-pub use lib::option::Option::{self, None, Some};
-pub use lib::ptr;
-pub use lib::result::Result::{self, Err, Ok};
+pub use crate::lib::clone::Clone;
+pub use crate::lib::convert::{From, Into};
+pub use crate::lib::default::Default;
+pub use crate::lib::fmt::{self, Formatter};
+pub use crate::lib::marker::PhantomData;
+pub use crate::lib::option::Option::{self, None, Some};
+pub use crate::lib::ptr;
+pub use crate::lib::result::Result::{self, Err, Ok};
 
 pub use self::string::from_utf8_lossy;
 
 #[cfg(any(feature = "alloc", feature = "std"))]
-pub use lib::{ToString, Vec};
+pub use crate::lib::{ToString, Vec};
 
 #[cfg(not(no_core_try_from))]
-pub use lib::convert::TryFrom;
+pub use crate::lib::convert::TryFrom;
 
 mod string {
-    use lib::*;
+    use crate::lib::*;
 
     #[cfg(any(feature = "std", feature = "alloc"))]
     pub fn from_utf8_lossy(bytes: &[u8]) -> Cow<str> {

serde/src/private/ser.rs

@@ -1,6 +1,6 @@
-use lib::*;
+use crate::lib::*;
 
-use ser::{self, Impossible, Serialize, SerializeMap, SerializeStruct, Serializer};
+use crate::ser::{self, Impossible, Serialize, SerializeMap, SerializeStruct, Serializer};
 
 #[cfg(any(feature = "std", feature = "alloc"))]
 use self::content::{
@@ -182,14 +182,14 @@ where
     }
 
     fn serialize_unit(self) -> Result<Self::Ok, Self::Error> {
-        let mut map = try!(self.delegate.serialize_map(Some(1)));
-        try!(map.serialize_entry(self.tag, self.variant_name));
+        let mut map = tri!(self.delegate.serialize_map(Some(1)));
+        tri!(map.serialize_entry(self.tag, self.variant_name));
         map.end()
     }
 
     fn serialize_unit_struct(self, _: &'static str) -> Result<Self::Ok, Self::Error> {
-        let mut map = try!(self.delegate.serialize_map(Some(1)));
-        try!(map.serialize_entry(self.tag, self.variant_name));
+        let mut map = tri!(self.delegate.serialize_map(Some(1)));
+        tri!(map.serialize_entry(self.tag, self.variant_name));
         map.end()
     }
 
@@ -199,9 +199,9 @@ where
         _: u32,
         inner_variant: &'static str,
     ) -> Result<Self::Ok, Self::Error> {
-        let mut map = try!(self.delegate.serialize_map(Some(2)));
-        try!(map.serialize_entry(self.tag, self.variant_name));
-        try!(map.serialize_entry(inner_variant, &()));
+        let mut map = tri!(self.delegate.serialize_map(Some(2)));
+        tri!(map.serialize_entry(self.tag, self.variant_name));
+        tri!(map.serialize_entry(inner_variant, &()));
         map.end()
     }
 
@@ -226,9 +226,9 @@ where
     where
         T: Serialize,
     {
-        let mut map = try!(self.delegate.serialize_map(Some(2)));
-        try!(map.serialize_entry(self.tag, self.variant_name));
-        try!(map.serialize_entry(inner_variant, inner_value));
+        let mut map = tri!(self.delegate.serialize_map(Some(2)));
+        tri!(map.serialize_entry(self.tag, self.variant_name));
+        tri!(map.serialize_entry(inner_variant, inner_value));
         map.end()
     }
 
@@ -269,9 +269,9 @@ where
         inner_variant: &'static str,
         len: usize,
     ) -> Result<Self::SerializeTupleVariant, Self::Error> {
-        let mut map = try!(self.delegate.serialize_map(Some(2)));
-        try!(map.serialize_entry(self.tag, self.variant_name));
-        try!(map.serialize_key(inner_variant));
+        let mut map = tri!(self.delegate.serialize_map(Some(2)));
+        tri!(map.serialize_entry(self.tag, self.variant_name));
+        tri!(map.serialize_key(inner_variant));
         Ok(SerializeTupleVariantAsMapValue::new(
             map,
             inner_variant,
@@ -280,8 +280,8 @@ where
     }
 
     fn serialize_map(self, len: Option<usize>) -> Result<Self::SerializeMap, Self::Error> {
-        let mut map = try!(self.delegate.serialize_map(len.map(|len| len + 1)));
-        try!(map.serialize_entry(self.tag, self.variant_name));
+        let mut map = tri!(self.delegate.serialize_map(len.map(|len| len + 1)));
+        tri!(map.serialize_entry(self.tag, self.variant_name));
         Ok(map)
     }
 
@@ -290,8 +290,8 @@ where
         name: &'static str,
         len: usize,
     ) -> Result<Self::SerializeStruct, Self::Error> {
-        let mut state = try!(self.delegate.serialize_struct(name, len + 1));
-        try!(state.serialize_field(self.tag, self.variant_name));
+        let mut state = tri!(self.delegate.serialize_struct(name, len + 1));
+        tri!(state.serialize_field(self.tag, self.variant_name));
         Ok(state)
     }
 
@@ -316,9 +316,9 @@ where
         inner_variant: &'static str,
         len: usize,
     ) -> Result<Self::SerializeStructVariant, Self::Error> {
-        let mut map = try!(self.delegate.serialize_map(Some(2)));
-        try!(map.serialize_entry(self.tag, self.variant_name));
-        try!(map.serialize_key(inner_variant));
+        let mut map = tri!(self.delegate.serialize_map(Some(2)));
+        tri!(map.serialize_entry(self.tag, self.variant_name));
+        tri!(map.serialize_key(inner_variant));
         Ok(SerializeStructVariantAsMapValue::new(
             map,
             inner_variant,
@@ -337,9 +337,9 @@ where
 
 #[cfg(any(feature = "std", feature = "alloc"))]
 mod content {
-    use lib::*;
+    use crate::lib::*;
 
-    use ser::{self, Serialize, Serializer};
+    use crate::ser::{self, Serialize, Serializer};
 
     pub struct SerializeTupleVariantAsMapValue<M> {
         map: M,
@@ -368,13 +368,13 @@ mod content {
         where
             T: Serialize,
         {
-            let value = try!(value.serialize(ContentSerializer::<M::Error>::new()));
+            let value = tri!(value.serialize(ContentSerializer::<M::Error>::new()));
             self.fields.push(value);
             Ok(())
         }
 
         fn end(mut self) -> Result<M::Ok, M::Error> {
-            try!(self
+            tri!(self
                 .map
                 .serialize_value(&Content::TupleStruct(self.name, self.fields)));
             self.map.end()
@@ -412,13 +412,13 @@ mod content {
         where
             T: Serialize,
         {
-            let value = try!(value.serialize(ContentSerializer::<M::Error>::new()));
+            let value = tri!(value.serialize(ContentSerializer::<M::Error>::new()));
             self.fields.push((key, value));
             Ok(())
         }
 
         fn end(mut self) -> Result<M::Ok, M::Error> {
-            try!(self
+            tri!(self
                 .map
                 .serialize_value(&Content::Struct(self.name, self.fields)));
             self.map.end()
@@ -499,50 +499,50 @@ mod content {
                 }
                 Content::Seq(ref elements) => elements.serialize(serializer),
                 Content::Tuple(ref elements) => {
-                    use ser::SerializeTuple;
-                    let mut tuple = try!(serializer.serialize_tuple(elements.len()));
+                    use crate::ser::SerializeTuple;
+                    let mut tuple = tri!(serializer.serialize_tuple(elements.len()));
                     for e in elements {
-                        try!(tuple.serialize_element(e));
+                        tri!(tuple.serialize_element(e));
                     }
                     tuple.end()
                 }
                 Content::TupleStruct(n, ref fields) => {
-                    use ser::SerializeTupleStruct;
-                    let mut ts = try!(serializer.serialize_tuple_struct(n, fields.len()));
+                    use crate::ser::SerializeTupleStruct;
+                    let mut ts = tri!(serializer.serialize_tuple_struct(n, fields.len()));
                     for f in fields {
-                        try!(ts.serialize_field(f));
+                        tri!(ts.serialize_field(f));
                     }
                     ts.end()
                 }
                 Content::TupleVariant(n, i, v, ref fields) => {
-                    use ser::SerializeTupleVariant;
-                    let mut tv = try!(serializer.serialize_tuple_variant(n, i, v, fields.len()));
+                    use crate::ser::SerializeTupleVariant;
+                    let mut tv = tri!(serializer.serialize_tuple_variant(n, i, v, fields.len()));
                     for f in fields {
-                        try!(tv.serialize_field(f));
+                        tri!(tv.serialize_field(f));
                     }
                     tv.end()
                 }
                 Content::Map(ref entries) => {
-                    use ser::SerializeMap;
-                    let mut map = try!(serializer.serialize_map(Some(entries.len())));
+                    use crate::ser::SerializeMap;
+                    let mut map = tri!(serializer.serialize_map(Some(entries.len())));
                     for (k, v) in entries {
-                        try!(map.serialize_entry(k, v));
+                        tri!(map.serialize_entry(k, v));
                     }
                     map.end()
                 }
                 Content::Struct(n, ref fields) => {
-                    use ser::SerializeStruct;
-                    let mut s = try!(serializer.serialize_struct(n, fields.len()));
+                    use crate::ser::SerializeStruct;
+                    let mut s = tri!(serializer.serialize_struct(n, fields.len()));
                     for &(k, ref v) in fields {
-                        try!(s.serialize_field(k, v));
+                        tri!(s.serialize_field(k, v));
                     }
                     s.end()
                 }
                 Content::StructVariant(n, i, v, ref fields) => {
-                    use ser::SerializeStructVariant;
-                    let mut sv = try!(serializer.serialize_struct_variant(n, i, v, fields.len()));
+                    use crate::ser::SerializeStructVariant;
+                    let mut sv = tri!(serializer.serialize_struct_variant(n, i, v, fields.len()));
                     for &(k, ref v) in fields {
-                        try!(sv.serialize_field(k, v));
+                        tri!(sv.serialize_field(k, v));
                     }
                     sv.end()
                 }
@@ -639,7 +639,7 @@ mod content {
         where
             T: Serialize,
         {
-            Ok(Content::Some(Box::new(try!(value.serialize(self)))))
+            Ok(Content::Some(Box::new(tri!(value.serialize(self)))))
         }
 
         fn serialize_unit(self) -> Result<Content, E> {
@@ -669,7 +669,7 @@ mod content {
         {
             Ok(Content::NewtypeStruct(
                 name,
-                Box::new(try!(value.serialize(self))),
+                Box::new(tri!(value.serialize(self))),
             ))
         }
 
@@ -687,7 +687,7 @@ mod content {
                 name,
                 variant_index,
                 variant,
-                Box::new(try!(value.serialize(self))),
+                Box::new(tri!(value.serialize(self))),
             ))
         }
 
@@ -786,7 +786,7 @@ mod content {
         where
             T: Serialize,
         {
-            let value = try!(value.serialize(ContentSerializer::<E>::new()));
+            let value = tri!(value.serialize(ContentSerializer::<E>::new()));
             self.elements.push(value);
             Ok(())
         }
@@ -812,7 +812,7 @@ mod content {
         where
             T: Serialize,
         {
-            let value = try!(value.serialize(ContentSerializer::<E>::new()));
+            let value = tri!(value.serialize(ContentSerializer::<E>::new()));
             self.elements.push(value);
             Ok(())
         }
@@ -839,7 +839,7 @@ mod content {
         where
             T: Serialize,
         {
-            let value = try!(value.serialize(ContentSerializer::<E>::new()));
+            let value = tri!(value.serialize(ContentSerializer::<E>::new()));
             self.fields.push(value);
             Ok(())
         }
@@ -868,7 +868,7 @@ mod content {
         where
             T: Serialize,
         {
-            let value = try!(value.serialize(ContentSerializer::<E>::new()));
+            let value = tri!(value.serialize(ContentSerializer::<E>::new()));
             self.fields.push(value);
             Ok(())
         }
@@ -900,7 +900,7 @@ mod content {
         where
             T: Serialize,
         {
-            let key = try!(key.serialize(ContentSerializer::<E>::new()));
+            let key = tri!(key.serialize(ContentSerializer::<E>::new()));
             self.key = Some(key);
             Ok(())
         }
@@ -913,7 +913,7 @@ mod content {
                 .key
                 .take()
                 .expect("serialize_value called before serialize_key");
-            let value = try!(value.serialize(ContentSerializer::<E>::new()));
+            let value = tri!(value.serialize(ContentSerializer::<E>::new()));
             self.entries.push((key, value));
             Ok(())
         }
@@ -927,8 +927,8 @@ mod content {
             K: Serialize,
             V: Serialize,
         {
-            let key = try!(key.serialize(ContentSerializer::<E>::new()));
-            let value = try!(value.serialize(ContentSerializer::<E>::new()));
+            let key = tri!(key.serialize(ContentSerializer::<E>::new()));
+            let value = tri!(value.serialize(ContentSerializer::<E>::new()));
             self.entries.push((key, value));
             Ok(())
         }
@@ -951,7 +951,7 @@ mod content {
         where
             T: Serialize,
         {
-            let value = try!(value.serialize(ContentSerializer::<E>::new()));
+            let value = tri!(value.serialize(ContentSerializer::<E>::new()));
             self.fields.push((key, value));
             Ok(())
         }
@@ -980,7 +980,7 @@ mod content {
         where
             T: Serialize,
         {
-            let value = try!(value.serialize(ContentSerializer::<E>::new()));
+            let value = tri!(value.serialize(ContentSerializer::<E>::new()));
             self.fields.push((key, value));
             Ok(())
         }
@@ -1025,7 +1025,7 @@ where
     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 SerializeTupleVariant = FlatMapSerializeTupleVariantAsMapValue<'a, M>;
     type SerializeStructVariant = FlatMapSerializeStructVariantAsMapValue<'a, M>;
 
     fn serialize_bool(self, _: bool) -> Result<Self::Ok, Self::Error> {
@@ -1133,7 +1133,7 @@ where
     where
         T: Serialize,
     {
-        try!(self.0.serialize_key(variant));
+        tri!(self.0.serialize_key(variant));
         self.0.serialize_value(value)
     }
 
@@ -1157,10 +1157,11 @@ where
         self,
         _: &'static str,
         _: u32,
-        _: &'static str,
+        variant: &'static str,
         _: usize,
     ) -> Result<Self::SerializeTupleVariant, Self::Error> {
-        Err(Self::bad_type(Unsupported::Enum))
+        tri!(self.0.serialize_key(variant));
+        Ok(FlatMapSerializeTupleVariantAsMapValue::new(self.0))
     }
 
     fn serialize_map(self, _: Option<usize>) -> Result<Self::SerializeMap, Self::Error> {
@@ -1182,7 +1183,7 @@ where
         inner_variant: &'static str,
         _: usize,
     ) -> Result<Self::SerializeStructVariant, Self::Error> {
-        try!(self.0.serialize_key(inner_variant));
+        tri!(self.0.serialize_key(inner_variant));
         Ok(FlatMapSerializeStructVariantAsMapValue::new(
             self.0,
             inner_variant,
@@ -1259,6 +1260,52 @@ where
     }
 }
 
+////////////////////////////////////////////////////////////////////////////////////////////////////
+
+#[cfg(any(feature = "std", feature = "alloc"))]
+pub struct FlatMapSerializeTupleVariantAsMapValue<'a, M: 'a> {
+    map: &'a mut M,
+    fields: Vec<Content>,
+}
+
+#[cfg(any(feature = "std", feature = "alloc"))]
+impl<'a, M> FlatMapSerializeTupleVariantAsMapValue<'a, M>
+where
+    M: SerializeMap + 'a,
+{
+    fn new(map: &'a mut M) -> Self {
+        FlatMapSerializeTupleVariantAsMapValue {
+            map,
+            fields: Vec::new(),
+        }
+    }
+}
+
+#[cfg(any(feature = "std", feature = "alloc"))]
+impl<'a, M> ser::SerializeTupleVariant for FlatMapSerializeTupleVariantAsMapValue<'a, M>
+where
+    M: SerializeMap + 'a,
+{
+    type Ok = ();
+    type Error = M::Error;
+
+    fn serialize_field<T: ?Sized>(&mut self, value: &T) -> Result<(), Self::Error>
+    where
+        T: Serialize,
+    {
+        let value = tri!(value.serialize(ContentSerializer::<M::Error>::new()));
+        self.fields.push(value);
+        Ok(())
+    }
+
+    fn end(self) -> Result<(), Self::Error> {
+        tri!(self.map.serialize_value(&Content::Seq(self.fields)));
+        Ok(())
+    }
+}
+
+////////////////////////////////////////////////////////////////////////////////////////////////////
+
 #[cfg(any(feature = "std", feature = "alloc"))]
 pub struct FlatMapSerializeStructVariantAsMapValue<'a, M: 'a> {
     map: &'a mut M,
@@ -1296,13 +1343,13 @@ where
     where
         T: Serialize,
     {
-        let value = try!(value.serialize(ContentSerializer::<M::Error>::new()));
+        let value = tri!(value.serialize(ContentSerializer::<M::Error>::new()));
         self.fields.push((key, value));
         Ok(())
     }
 
     fn end(self) -> Result<(), Self::Error> {
-        try!(self
+        tri!(self
             .map
             .serialize_value(&Content::Struct(self.name, self.fields)));
         Ok(())

serde/src/private/size_hint.rs

@@ -1,4 +1,4 @@
-use lib::*;
+use crate::lib::*;
 
 pub fn from_bounds<I>(iter: &I) -> Option<usize>
 where

serde/src/ser/fmt.rs

@@ -1,5 +1,5 @@
-use lib::*;
-use ser::{Error, Impossible, Serialize, Serializer};
+use crate::lib::*;
+use crate::ser::{Error, Impossible, Serialize, Serializer};
 
 impl Error for fmt::Error {
     fn custom<T: Display>(_msg: T) -> Self {

serde/src/ser/impls.rs

@@ -1,6 +1,6 @@
-use lib::*;
+use crate::lib::*;
 
-use ser::{Error, Serialize, SerializeTuple, Serializer};
+use crate::ser::{Error, Serialize, SerializeTuple, Serializer};
 
 ////////////////////////////////////////////////////////////////////////////////
 
@@ -133,7 +133,7 @@ impl<T> Serialize for [T; 0] {
     where
         S: Serializer,
     {
-        try!(serializer.serialize_tuple(0)).end()
+        tri!(serializer.serialize_tuple(0)).end()
     }
 }
 
@@ -149,9 +149,9 @@ macro_rules! array_impls {
                 where
                     S: Serializer,
                 {
-                    let mut seq = try!(serializer.serialize_tuple($len));
+                    let mut seq = tri!(serializer.serialize_tuple($len));
                     for e in self {
-                        try!(seq.serialize_element(e));
+                        tri!(seq.serialize_element(e));
                     }
                     seq.end()
                 }
@@ -248,9 +248,9 @@ where
         S: Serializer,
     {
         use super::SerializeStruct;
-        let mut state = try!(serializer.serialize_struct("Range", 2));
-        try!(state.serialize_field("start", &self.start));
-        try!(state.serialize_field("end", &self.end));
+        let mut state = tri!(serializer.serialize_struct("Range", 2));
+        tri!(state.serialize_field("start", &self.start));
+        tri!(state.serialize_field("end", &self.end));
         state.end()
     }
 }
@@ -266,15 +266,14 @@ where
         S: Serializer,
     {
         use super::SerializeStruct;
-        let mut state = try!(serializer.serialize_struct("RangeFrom", 1));
-        try!(state.serialize_field("start", &self.start));
+        let mut state = tri!(serializer.serialize_struct("RangeFrom", 1));
+        tri!(state.serialize_field("start", &self.start));
         state.end()
     }
 }
 
 ////////////////////////////////////////////////////////////////////////////////
 
-#[cfg(not(no_range_inclusive))]
 impl<Idx> Serialize for RangeInclusive<Idx>
 where
     Idx: Serialize,
@@ -284,9 +283,9 @@ where
         S: Serializer,
     {
         use super::SerializeStruct;
-        let mut state = try!(serializer.serialize_struct("RangeInclusive", 2));
-        try!(state.serialize_field("start", &self.start()));
-        try!(state.serialize_field("end", &self.end()));
+        let mut state = tri!(serializer.serialize_struct("RangeInclusive", 2));
+        tri!(state.serialize_field("start", &self.start()));
+        tri!(state.serialize_field("end", &self.end()));
         state.end()
     }
 }
@@ -302,15 +301,14 @@ where
         S: Serializer,
     {
         use super::SerializeStruct;
-        let mut state = try!(serializer.serialize_struct("RangeTo", 1));
-        try!(state.serialize_field("end", &self.end));
+        let mut state = tri!(serializer.serialize_struct("RangeTo", 1));
+        tri!(state.serialize_field("end", &self.end));
         state.end()
     }
 }
 
 ////////////////////////////////////////////////////////////////////////////////
 
-#[cfg(any(not(no_ops_bound), all(feature = "std", not(no_collections_bound))))]
 impl<T> Serialize for Bound<T>
 where
     T: Serialize,
@@ -367,9 +365,9 @@ macro_rules! tuple_impls {
                 where
                     S: Serializer,
                 {
-                    let mut tuple = try!(serializer.serialize_tuple($len));
+                    let mut tuple = tri!(serializer.serialize_tuple($len));
                     $(
-                        try!(tuple.serialize_element(&self.$n));
+                        tri!(tuple.serialize_element(&self.$n));
                     )+
                     tuple.end()
                 }
@@ -538,7 +536,6 @@ where
 macro_rules! nonzero_integers {
     ($($T:ident,)+) => {
         $(
-            #[cfg(not(no_num_nonzero))]
             impl Serialize for num::$T {
                 fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
                 where
@@ -662,16 +659,15 @@ where
 
 ////////////////////////////////////////////////////////////////////////////////
 
-#[cfg(any(feature = "std", not(no_core_duration)))]
 impl Serialize for Duration {
     fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
     where
         S: Serializer,
     {
         use super::SerializeStruct;
-        let mut state = try!(serializer.serialize_struct("Duration", 2));
-        try!(state.serialize_field("secs", &self.as_secs()));
-        try!(state.serialize_field("nanos", &self.subsec_nanos()));
+        let mut state = tri!(serializer.serialize_struct("Duration", 2));
+        tri!(state.serialize_field("secs", &self.as_secs()));
+        tri!(state.serialize_field("nanos", &self.subsec_nanos()));
         state.end()
     }
 }
@@ -689,9 +685,9 @@ impl Serialize for SystemTime {
             Ok(duration_since_epoch) => duration_since_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()));
+        let mut state = tri!(serializer.serialize_struct("SystemTime", 2));
+        tri!(state.serialize_field("secs_since_epoch", &duration_since_epoch.as_secs()));
+        tri!(state.serialize_field("nanos_since_epoch", &duration_since_epoch.subsec_nanos()));
         state.end()
     }
 }
@@ -963,7 +959,6 @@ where
     }
 }
 
-#[cfg(not(no_core_reverse))]
 impl<T> Serialize for Reverse<T>
 where
     T: Serialize,

serde/src/ser/impossible.rs

@@ -1,8 +1,8 @@
 //! This module contains `Impossible` serializer and its implementations.
 
-use lib::*;
+use crate::lib::*;
 
-use ser::{
+use crate::ser::{
     self, Serialize, SerializeMap, SerializeSeq, SerializeStruct, SerializeStructVariant,
     SerializeTuple, SerializeTupleStruct, SerializeTupleVariant,
 };

serde/src/ser/mod.rs

@@ -107,7 +107,7 @@
 //! [derive section of the manual]: https://serde.rs/derive.html
 //! [data formats]: https://serde.rs/#data-formats
 
-use lib::*;
+use crate::lib::*;
 
 mod fmt;
 mod impls;
@@ -115,15 +115,15 @@ mod impossible;
 
 pub use self::impossible::Impossible;
 
+#[cfg(not(any(feature = "std", feature = "unstable")))]
+#[doc(no_inline)]
+pub use crate::std_error::Error as StdError;
 #[cfg(all(feature = "unstable", not(feature = "std")))]
-#[doc(inline)]
+#[doc(no_inline)]
 pub use core::error::Error as StdError;
 #[cfg(feature = "std")]
 #[doc(no_inline)]
 pub use std::error::Error as StdError;
-#[cfg(not(any(feature = "std", feature = "unstable")))]
-#[doc(no_inline)]
-pub use std_error::Error as StdError;
 
 ////////////////////////////////////////////////////////////////////////////////
 
@@ -1279,22 +1279,9 @@ pub trait Serializer: Sized {
         I: IntoIterator,
         <I as IntoIterator>::Item: Serialize,
     {
-        let iter = iter.into_iter();
-        let mut serializer = try!(self.serialize_seq(iterator_len_hint(&iter)));
-
-        #[cfg(not(no_iterator_try_fold))]
-        {
-            let mut iter = iter;
-            try!(iter.try_for_each(|item| serializer.serialize_element(&item)));
-        }
-
-        #[cfg(no_iterator_try_fold)]
-        {
-            for item in iter {
-                try!(serializer.serialize_element(&item));
-            }
-        }
-
+        let mut iter = iter.into_iter();
+        let mut serializer = tri!(self.serialize_seq(iterator_len_hint(&iter)));
+        tri!(iter.try_for_each(|item| serializer.serialize_element(&item)));
         serializer.end()
     }
 
@@ -1330,22 +1317,9 @@ pub trait Serializer: Sized {
         V: Serialize,
         I: IntoIterator<Item = (K, V)>,
     {
-        let iter = iter.into_iter();
-        let mut serializer = try!(self.serialize_map(iterator_len_hint(&iter)));
-
-        #[cfg(not(no_iterator_try_fold))]
-        {
-            let mut iter = iter;
-            try!(iter.try_for_each(|(key, value)| serializer.serialize_entry(&key, &value)));
-        }
-
-        #[cfg(no_iterator_try_fold)]
-        {
-            for (key, value) in iter {
-                try!(serializer.serialize_entry(&key, &value));
-            }
-        }
-
+        let mut iter = iter.into_iter();
+        let mut serializer = tri!(self.serialize_map(iterator_len_hint(&iter)));
+        tri!(iter.try_for_each(|(key, value)| serializer.serialize_entry(&key, &value)));
         serializer.end()
     }
 
@@ -1839,7 +1813,7 @@ pub trait SerializeMap {
         K: Serialize,
         V: Serialize,
     {
-        try!(self.serialize_key(key));
+        tri!(self.serialize_key(key));
         self.serialize_value(value)
     }
 

serde/src/std_error.rs

@@ -1,4 +1,4 @@
-use lib::{Debug, Display};
+use crate::lib::{Debug, Display};
 
 /// Either a re-export of std::error::Error or a new identical trait, depending
 /// on whether Serde's "std" feature is enabled.

serde_derive/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "serde_derive"
-version = "1.0.176" # remember to update html_root_url
+version = "1.0.180" # remember to update html_root_url
 authors = ["Erick Tryzelaar <erick.tryzelaar@gmail.com>", "David Tolnay <dtolnay@gmail.com>"]
 categories = ["no-std", "no-std::no-alloc"]
 description = "Macros 1.1 implementation of #[derive(Serialize, Deserialize)]"
@@ -23,7 +23,7 @@ proc-macro = true
 [dependencies]
 proc-macro2 = "1.0"
 quote = "1.0"
-syn = "2.0.25"
+syn = "2.0.28"
 
 [dev-dependencies]
 serde = { version = "1", path = "../serde" }

serde_derive/src/de.rs

@@ -710,14 +710,14 @@ fn deserialize_seq(
                     let span = field.original.span();
                     let func =
                         quote_spanned!(span=> _serde::de::SeqAccess::next_element::<#field_ty>);
-                    quote!(try!(#func(&mut __seq)))
+                    quote!(#func(&mut __seq)?)
                 }
                 Some(path) => {
                     let (wrapper, wrapper_ty) = wrap_deserialize_field_with(params, field.ty, path);
                     quote!({
                         #wrapper
                         _serde::__private::Option::map(
-                            try!(_serde::de::SeqAccess::next_element::<#wrapper_ty>(&mut __seq)),
+                            _serde::de::SeqAccess::next_element::<#wrapper_ty>(&mut __seq)?,
                             |__wrap| __wrap.value)
                     })
                 }
@@ -824,8 +824,8 @@ fn deserialize_seq_in_place(
             let write = match field.attrs.deserialize_with() {
                 None => {
                     quote! {
-                        if let _serde::__private::None = try!(_serde::de::SeqAccess::next_element_seed(&mut __seq,
-                            _serde::__private::de::InPlaceSeed(&mut self.place.#member)))
+                        if let _serde::__private::None = _serde::de::SeqAccess::next_element_seed(&mut __seq,
+                            _serde::__private::de::InPlaceSeed(&mut self.place.#member))?
                         {
                             #value_if_none
                         }
@@ -835,7 +835,7 @@ fn deserialize_seq_in_place(
                     let (wrapper, wrapper_ty) = wrap_deserialize_field_with(params, field.ty, path);
                     quote!({
                         #wrapper
-                        match try!(_serde::de::SeqAccess::next_element::<#wrapper_ty>(&mut __seq)) {
+                        match _serde::de::SeqAccess::next_element::<#wrapper_ty>(&mut __seq)? {
                             _serde::__private::Some(__wrap) => {
                                 self.place.#member = __wrap.value;
                             }
@@ -887,12 +887,12 @@ fn deserialize_newtype_struct(
             let span = field.original.span();
             let func = quote_spanned!(span=> <#field_ty as _serde::Deserialize>::deserialize);
             quote! {
-                try!(#func(__e))
+                #func(__e)?
             }
         }
         Some(path) => {
             quote! {
-                try!(#path(__e))
+                #path(__e)?
             }
         }
     };
@@ -1364,7 +1364,7 @@ fn deserialize_externally_tagged_enum(
         }
     } else {
         quote! {
-            match try!(_serde::de::EnumAccess::variant(__data)) {
+            match _serde::de::EnumAccess::variant(__data)? {
                 #(#variant_arms)*
             }
         }
@@ -1444,9 +1444,9 @@ fn deserialize_internally_tagged_enum(
 
         #variants_stmt
 
-        let (__tag, __content) = try!(_serde::Deserializer::deserialize_any(
+        let (__tag, __content) = _serde::Deserializer::deserialize_any(
             __deserializer,
-            _serde::__private::de::TaggedContentVisitor::<__Field>::new(#tag, #expecting)));
+            _serde::__private::de::TaggedContentVisitor::<__Field>::new(#tag, #expecting))?;
         let __deserializer = _serde::__private::de::ContentDeserializer::<__D::Error>::new(__content);
 
         match __tag {
@@ -1554,7 +1554,7 @@ fn deserialize_adjacently_tagged_enum(
 
     // Advance the map by one key, returning early in case of error.
     let next_key = quote! {
-        try!(_serde::de::MapAccess::next_key_seed(&mut __map, #tag_or_content))
+        _serde::de::MapAccess::next_key_seed(&mut __map, #tag_or_content)?
     };
 
     // When allowing unknown fields, we want to transparently step through keys
@@ -1567,7 +1567,7 @@ fn deserialize_adjacently_tagged_enum(
             while let _serde::__private::Some(__k) = #next_key {
                 match __k {
                     _serde::__private::de::TagContentOtherField::Other => {
-                        let _ = try!(_serde::de::MapAccess::next_value::<_serde::de::IgnoredAny>(&mut __map));
+                        let _ = _serde::de::MapAccess::next_value::<_serde::de::IgnoredAny>(&mut __map)?;
                         continue;
                     },
                     _serde::__private::de::TagContentOtherField::Tag => {
@@ -1602,14 +1602,14 @@ fn deserialize_adjacently_tagged_enum(
 
     let finish_content_then_tag = if variant_arms.is_empty() {
         quote! {
-            match try!(_serde::de::MapAccess::next_value::<__Field>(&mut __map)) {}
+            match _serde::de::MapAccess::next_value::<__Field>(&mut __map)? {}
         }
     } else {
         quote! {
-            let __ret = try!(match try!(_serde::de::MapAccess::next_value(&mut __map)) {
+            let __ret = match _serde::de::MapAccess::next_value(&mut __map)? {
                 // Deserialize the buffered content now that we know the variant.
                 #(#variant_arms)*
-            });
+            }?;
             // Visit remaining keys, looking for duplicates.
             #visit_remaining_keys
         }
@@ -1662,7 +1662,7 @@ fn deserialize_adjacently_tagged_enum(
                     // First key is the tag.
                     _serde::__private::Some(_serde::__private::de::TagOrContentField::Tag) => {
                         // Parse the tag.
-                        let __field = try!(_serde::de::MapAccess::next_value(&mut __map));
+                        let __field = _serde::de::MapAccess::next_value(&mut __map)?;
                         // Visit the second key.
                         match #next_relevant_key {
                             // Second key is a duplicate of the tag.
@@ -1671,12 +1671,12 @@ fn deserialize_adjacently_tagged_enum(
                             }
                             // Second key is the content.
                             _serde::__private::Some(_serde::__private::de::TagOrContentField::Content) => {
-                                let __ret = try!(_serde::de::MapAccess::next_value_seed(&mut __map,
+                                let __ret = _serde::de::MapAccess::next_value_seed(&mut __map,
                                     __Seed {
                                         field: __field,
                                         marker: _serde::__private::PhantomData,
                                         lifetime: _serde::__private::PhantomData,
-                                    }));
+                                    })?;
                                 // Visit remaining keys, looking for duplicates.
                                 #visit_remaining_keys
                             }
@@ -1687,7 +1687,7 @@ fn deserialize_adjacently_tagged_enum(
                     // First key is the content.
                     _serde::__private::Some(_serde::__private::de::TagOrContentField::Content) => {
                         // Buffer up the content.
-                        let __content = try!(_serde::de::MapAccess::next_value::<_serde::__private::de::Content>(&mut __map));
+                        let __content = _serde::de::MapAccess::next_value::<_serde::__private::de::Content>(&mut __map)?;
                         // Visit the second key.
                         match #next_relevant_key {
                             // Second key is the tag.
@@ -1717,17 +1717,17 @@ fn deserialize_adjacently_tagged_enum(
                 __A: _serde::de::SeqAccess<#delife>,
             {
                 // Visit the first element - the tag.
-                match try!(_serde::de::SeqAccess::next_element(&mut __seq)) {
+                match _serde::de::SeqAccess::next_element(&mut __seq)? {
                     _serde::__private::Some(__field) => {
                         // Visit the second element - the content.
-                        match try!(_serde::de::SeqAccess::next_element_seed(
+                        match _serde::de::SeqAccess::next_element_seed(
                             &mut __seq,
                             __Seed {
                                 field: __field,
                                 marker: _serde::__private::PhantomData,
                                 lifetime: _serde::__private::PhantomData,
                             },
-                        )) {
+                        )? {
                             _serde::__private::Some(__ret) => _serde::__private::Ok(__ret),
                             // There is no second element.
                             _serde::__private::None => {
@@ -1797,7 +1797,7 @@ fn deserialize_untagged_enum_after(
     let fallthrough_msg = cattrs.expecting().unwrap_or(&fallthrough_msg);
 
     quote_block! {
-        let __content = try!(<_serde::__private::de::Content as _serde::Deserialize>::deserialize(__deserializer));
+        let __content = <_serde::__private::de::Content as _serde::Deserialize>::deserialize(__deserializer)?;
         let __deserializer = _serde::__private::de::ContentRefDeserializer::<__D::Error>::new(&__content);
 
         #(
@@ -1830,7 +1830,7 @@ fn deserialize_externally_tagged_variant(
         Style::Unit => {
             let this_value = &params.this_value;
             quote_block! {
-                try!(_serde::de::VariantAccess::unit_variant(__variant));
+                _serde::de::VariantAccess::unit_variant(__variant)?;
                 _serde::__private::Ok(#this_value::#variant_ident)
             }
         }
@@ -1879,7 +1879,7 @@ fn deserialize_internally_tagged_variant(
                 quote!((#default))
             });
             quote_block! {
-                try!(_serde::Deserializer::deserialize_any(#deserializer, _serde::__private::de::InternallyTaggedUnitVisitor::new(#type_name, #variant_name)));
+                _serde::Deserializer::deserialize_any(#deserializer, _serde::__private::de::InternallyTaggedUnitVisitor::new(#type_name, #variant_name))?;
                 _serde::__private::Ok(#this_value::#variant_ident #default)
             }
         }
@@ -1965,7 +1965,7 @@ fn deserialize_externally_tagged_newtype_variant(
     if field.attrs.skip_deserializing() {
         let default = Expr(expr_is_missing(field, cattrs));
         return quote_block! {
-            try!(_serde::de::VariantAccess::unit_variant(__variant));
+            _serde::de::VariantAccess::unit_variant(__variant)?;
             _serde::__private::Ok(#this_value::#variant_ident(#default))
         };
     }
@@ -2540,7 +2540,7 @@ fn deserialize_map(
                     let func =
                         quote_spanned!(span=> _serde::de::MapAccess::next_value::<#field_ty>);
                     quote! {
-                        try!(#func(&mut __map))
+                        #func(&mut __map)?
                     }
                 }
                 Some(path) => {
@@ -2572,14 +2572,14 @@ fn deserialize_map(
             __Field::__other(__name) => {
                 __collect.push(_serde::__private::Some((
                     __name,
-                    try!(_serde::de::MapAccess::next_value(&mut __map)))));
+                    _serde::de::MapAccess::next_value(&mut __map)?)));
             }
         })
     } else if cattrs.deny_unknown_fields() {
         None
     } else {
         Some(quote! {
-            _ => { let _ = try!(_serde::de::MapAccess::next_value::<_serde::de::IgnoredAny>(&mut __map)); }
+            _ => { let _ = _serde::de::MapAccess::next_value::<_serde::de::IgnoredAny>(&mut __map)?; }
         })
     };
 
@@ -2587,14 +2587,14 @@ fn deserialize_map(
     let match_keys = if cattrs.deny_unknown_fields() && all_skipped {
         quote! {
             // FIXME: Once feature(exhaustive_patterns) is stable:
-            // let _serde::__private::None::<__Field> = try!(_serde::de::MapAccess::next_key(&mut __map));
+            // let _serde::__private::None::<__Field> = _serde::de::MapAccess::next_key(&mut __map)?;
             _serde::__private::Option::map(
-                try!(_serde::de::MapAccess::next_key::<__Field>(&mut __map)),
+                _serde::de::MapAccess::next_key::<__Field>(&mut __map)?,
                 |__impossible| match __impossible {});
         }
     } else {
         quote! {
-            while let _serde::__private::Some(__key) = try!(_serde::de::MapAccess::next_key::<__Field>(&mut __map)) {
+            while let _serde::__private::Some(__key) = _serde::de::MapAccess::next_key::<__Field>(&mut __map)? {
                 match __key {
                     #(#value_arms)*
                     #ignored_arm
@@ -2630,10 +2630,10 @@ fn deserialize_map(
                 Some(path) => quote!(#path),
             };
             quote! {
-                let #name: #field_ty = try!(#func(
+                let #name: #field_ty = #func(
                     _serde::__private::de::FlatMapDeserializer(
                         &mut __collect,
-                        _serde::__private::PhantomData)));
+                        _serde::__private::PhantomData))?;
             }
         });
 
@@ -2780,7 +2780,7 @@ fn deserialize_map_in_place(
             let visit = match field.attrs.deserialize_with() {
                 None => {
                     quote! {
-                        try!(_serde::de::MapAccess::next_value_seed(&mut __map, _serde::__private::de::InPlaceSeed(&mut self.place.#member)))
+                        _serde::de::MapAccess::next_value_seed(&mut __map, _serde::__private::de::InPlaceSeed(&mut self.place.#member))?
                     }
                 }
                 Some(path) => {
@@ -2812,7 +2812,7 @@ fn deserialize_map_in_place(
         None
     } else {
         Some(quote! {
-            _ => { let _ = try!(_serde::de::MapAccess::next_value::<_serde::de::IgnoredAny>(&mut __map)); }
+            _ => { let _ = _serde::de::MapAccess::next_value::<_serde::de::IgnoredAny>(&mut __map)?; }
         })
     };
 
@@ -2821,14 +2821,14 @@ fn deserialize_map_in_place(
     let match_keys = if cattrs.deny_unknown_fields() && all_skipped {
         quote! {
             // FIXME: Once feature(exhaustive_patterns) is stable:
-            // let _serde::__private::None::<__Field> = try!(_serde::de::MapAccess::next_key(&mut __map));
+            // let _serde::__private::None::<__Field> = _serde::de::MapAccess::next_key(&mut __map)?;
             _serde::__private::Option::map(
-                try!(_serde::de::MapAccess::next_key::<__Field>(&mut __map)),
+                _serde::de::MapAccess::next_key::<__Field>(&mut __map)?,
                 |__impossible| match __impossible {});
         }
     } else {
         quote! {
-            while let _serde::__private::Some(__key) = try!(_serde::de::MapAccess::next_key::<__Field>(&mut __map)) {
+            while let _serde::__private::Some(__key) = _serde::de::MapAccess::next_key::<__Field>(&mut __map)? {
                 match __key {
                     #(#value_arms_from)*
                     #ignored_arm
@@ -2925,7 +2925,7 @@ fn wrap_deserialize_with(
                 __D: _serde::Deserializer<#delife>,
             {
                 _serde::__private::Ok(__DeserializeWith {
-                    value: try!(#deserialize_with(__deserializer)),
+                    value: #deserialize_with(__deserializer)?,
                     phantom: _serde::__private::PhantomData,
                     lifetime: _serde::__private::PhantomData,
                 })
@@ -3035,7 +3035,7 @@ fn expr_is_missing(field: &Field, cattrs: &attr::Container) -> Fragment {
             let span = field.original.span();
             let func = quote_spanned!(span=> _serde::__private::de::missing_field);
             quote_expr! {
-                try!(#func(#name))
+                #func(#name)?
             }
         }
         Some(_) => {

serde_derive/src/dummy.rs

@@ -1,10 +1,7 @@
-use crate::try;
 use proc_macro2::TokenStream;
 use quote::quote;
 
 pub fn wrap_in_const(serde_path: Option<&syn::Path>, code: TokenStream) -> TokenStream {
-    let try_replacement = try::replacement();
-
     let use_serde = match serde_path {
         Some(path) => quote! {
             use #path as _serde;
@@ -20,7 +17,6 @@ pub fn wrap_in_const(serde_path: Option<&syn::Path>, code: TokenStream) -> Token
         #[allow(non_upper_case_globals, unused_attributes, unused_qualifications)]
         const _: () = {
             #use_serde
-            #try_replacement
             #code
         };
     }

serde_derive/src/internals/ast.rs

@@ -86,9 +86,12 @@ impl<'a> Container<'a> {
                         if field.attrs.flatten() {
                             has_flatten = true;
                         }
-                        field
-                            .attrs
-                            .rename_by_rules(variant.attrs.rename_all_rules());
+                        field.attrs.rename_by_rules(
+                            variant
+                                .attrs
+                                .rename_all_rules()
+                                .or(attrs.rename_all_fields_rules()),
+                        );
                     }
                 }
             }
@@ -119,7 +122,7 @@ impl<'a> Container<'a> {
 }
 
 impl<'a> Data<'a> {
-    pub fn all_fields(&'a self) -> Box<Iterator<Item = &'a Field<'a>> + 'a> {
+    pub fn all_fields(&'a self) -> Box<dyn Iterator<Item = &'a Field<'a>> + 'a> {
         match self {
             Data::Enum(variants) => {
                 Box::new(variants.iter().flat_map(|variant| variant.fields.iter()))

serde_derive/src/internals/attr.rs

@@ -192,11 +192,23 @@ impl Name {
     }
 }
 
+#[derive(Copy, Clone)]
 pub struct RenameAllRules {
     serialize: RenameRule,
     deserialize: RenameRule,
 }
 
+impl RenameAllRules {
+    /// Returns a new `RenameAllRules` with the individual rules of `self` and
+    /// `other_rules` joined by `RenameRules::or`.
+    pub fn or(self, other_rules: Self) -> Self {
+        Self {
+            serialize: self.serialize.or(other_rules.serialize),
+            deserialize: self.deserialize.or(other_rules.deserialize),
+        }
+    }
+}
+
 /// Represents struct or enum attribute information.
 pub struct Container {
     name: Name,
@@ -204,6 +216,7 @@ pub struct Container {
     deny_unknown_fields: bool,
     default: Default,
     rename_all_rules: RenameAllRules,
+    rename_all_fields_rules: RenameAllRules,
     ser_bound: Option<Vec<syn::WherePredicate>>,
     de_bound: Option<Vec<syn::WherePredicate>>,
     tag: TagType,
@@ -287,6 +300,8 @@ impl Container {
         let mut default = Attr::none(cx, DEFAULT);
         let mut rename_all_ser_rule = Attr::none(cx, RENAME_ALL);
         let mut rename_all_de_rule = Attr::none(cx, RENAME_ALL);
+        let mut rename_all_fields_ser_rule = Attr::none(cx, RENAME_ALL_FIELDS);
+        let mut rename_all_fields_de_rule = Attr::none(cx, RENAME_ALL_FIELDS);
         let mut ser_bound = Attr::none(cx, BOUND);
         let mut de_bound = Attr::none(cx, BOUND);
         let mut untagged = BoolAttr::none(cx, UNTAGGED);
@@ -340,6 +355,44 @@ impl Container {
                             }
                         }
                     }
+                } else if meta.path == RENAME_ALL_FIELDS {
+                    // #[serde(rename_all_fields = "foo")]
+                    // #[serde(rename_all_fields(serialize = "foo", deserialize = "bar"))]
+                    let one_name = meta.input.peek(Token![=]);
+                    let (ser, de) = get_renames(cx, RENAME_ALL_FIELDS, &meta)?;
+
+                    match item.data {
+                        syn::Data::Enum(_) => {
+                            if let Some(ser) = ser {
+                                match RenameRule::from_str(&ser.value()) {
+                                    Ok(rename_rule) => {
+                                        rename_all_fields_ser_rule.set(&meta.path, rename_rule);
+                                    }
+                                    Err(err) => cx.error_spanned_by(ser, err),
+                                }
+                            }
+                            if let Some(de) = de {
+                                match RenameRule::from_str(&de.value()) {
+                                    Ok(rename_rule) => {
+                                        rename_all_fields_de_rule.set(&meta.path, rename_rule);
+                                    }
+                                    Err(err) => {
+                                        if !one_name {
+                                            cx.error_spanned_by(de, err);
+                                        }
+                                    }
+                                }
+                            }
+                        }
+                        syn::Data::Struct(_) => {
+                            let msg = "#[serde(rename_all_fields)] can only be used on enums";
+                            cx.syn_error(meta.error(msg));
+                        }
+                        syn::Data::Union(_) => {
+                            let msg = "#[serde(rename_all_fields)] can only be used on enums";
+                            cx.syn_error(meta.error(msg));
+                        }
+                    }
                 } else if meta.path == TRANSPARENT {
                     // #[serde(transparent)]
                     transparent.set_true(meta.path);
@@ -357,16 +410,16 @@ impl Container {
                                     }
                                     syn::Fields::Unnamed(_) | syn::Fields::Unit => {
                                         let msg = "#[serde(default = \"...\")] can only be used on structs with named fields";
-                                        cx.error_spanned_by(fields, msg);
+                                        cx.syn_error(meta.error(msg));
                                     }
                                 },
-                                syn::Data::Enum(syn::DataEnum { enum_token, .. }) => {
+                                syn::Data::Enum(_) => {
                                     let msg = "#[serde(default = \"...\")] can only be used on structs with named fields";
-                                    cx.error_spanned_by(enum_token, msg);
+                                    cx.syn_error(meta.error(msg));
                                 }
-                                syn::Data::Union(syn::DataUnion { union_token, .. }) => {
+                                syn::Data::Union(_) => {
                                     let msg = "#[serde(default = \"...\")] can only be used on structs with named fields";
-                                    cx.error_spanned_by(union_token, msg);
+                                    cx.syn_error(meta.error(msg));
                                 }
                             }
                         }
@@ -382,13 +435,13 @@ impl Container {
                                     cx.error_spanned_by(fields, msg);
                                 }
                             },
-                            syn::Data::Enum(syn::DataEnum { enum_token, .. }) => {
+                            syn::Data::Enum(_) => {
                                 let msg = "#[serde(default)] can only be used on structs with named fields";
-                                cx.error_spanned_by(enum_token, msg);
+                                cx.syn_error(meta.error(msg));
                             }
-                            syn::Data::Union(syn::DataUnion { union_token, .. }) => {
+                            syn::Data::Union(_) => {
                                 let msg = "#[serde(default)] can only be used on structs with named fields";
-                                cx.error_spanned_by(union_token, msg);
+                                cx.syn_error(meta.error(msg));
                             }
                         }
                     }
@@ -404,13 +457,13 @@ impl Container {
                         syn::Data::Enum(_) => {
                             untagged.set_true(&meta.path);
                         }
-                        syn::Data::Struct(syn::DataStruct { struct_token, .. }) => {
+                        syn::Data::Struct(_) => {
                             let msg = "#[serde(untagged)] can only be used on enums";
-                            cx.error_spanned_by(struct_token, msg);
+                            cx.syn_error(meta.error(msg));
                         }
-                        syn::Data::Union(syn::DataUnion { union_token, .. }) => {
+                        syn::Data::Union(_) => {
                             let msg = "#[serde(untagged)] can only be used on enums";
-                            cx.error_spanned_by(union_token, msg);
+                            cx.syn_error(meta.error(msg));
                         }
                     }
                 } else if meta.path == TAG {
@@ -426,12 +479,12 @@ impl Container {
                                 }
                                 syn::Fields::Unnamed(_) | syn::Fields::Unit => {
                                     let msg = "#[serde(tag = \"...\")] can only be used on enums and structs with named fields";
-                                    cx.error_spanned_by(fields, msg);
+                                    cx.syn_error(meta.error(msg));
                                 }
                             },
-                            syn::Data::Union(syn::DataUnion { union_token, .. }) => {
+                            syn::Data::Union(_) => {
                                 let msg = "#[serde(tag = \"...\")] can only be used on enums and structs with named fields";
-                                cx.error_spanned_by(union_token, msg);
+                                cx.syn_error(meta.error(msg));
                             }
                         }
                     }
@@ -442,13 +495,13 @@ impl Container {
                             syn::Data::Enum(_) => {
                                 content.set(&meta.path, s.value());
                             }
-                            syn::Data::Struct(syn::DataStruct { struct_token, .. }) => {
+                            syn::Data::Struct(_) => {
                                 let msg = "#[serde(content = \"...\")] can only be used on enums";
-                                cx.error_spanned_by(struct_token, msg);
+                                cx.syn_error(meta.error(msg));
                             }
-                            syn::Data::Union(syn::DataUnion { union_token, .. }) => {
+                            syn::Data::Union(_) => {
                                 let msg = "#[serde(content = \"...\")] can only be used on enums";
-                                cx.error_spanned_by(union_token, msg);
+                                cx.syn_error(meta.error(msg));
                             }
                         }
                     }
@@ -527,6 +580,10 @@ impl Container {
                 serialize: rename_all_ser_rule.get().unwrap_or(RenameRule::None),
                 deserialize: rename_all_de_rule.get().unwrap_or(RenameRule::None),
             },
+            rename_all_fields_rules: RenameAllRules {
+                serialize: rename_all_fields_ser_rule.get().unwrap_or(RenameRule::None),
+                deserialize: rename_all_fields_de_rule.get().unwrap_or(RenameRule::None),
+            },
             ser_bound: ser_bound.get(),
             de_bound: de_bound.get(),
             tag: decide_tag(cx, item, untagged, internal_tag, content),
@@ -546,8 +603,12 @@ impl Container {
         &self.name
     }
 
-    pub fn rename_all_rules(&self) -> &RenameAllRules {
-        &self.rename_all_rules
+    pub fn rename_all_rules(&self) -> RenameAllRules {
+        self.rename_all_rules
+    }
+
+    pub fn rename_all_fields_rules(&self) -> RenameAllRules {
+        self.rename_all_fields_rules
     }
 
     pub fn transparent(&self) -> bool {
@@ -920,7 +981,7 @@ impl Variant {
         self.name.deserialize_aliases()
     }
 
-    pub fn rename_by_rules(&mut self, rules: &RenameAllRules) {
+    pub fn rename_by_rules(&mut self, rules: RenameAllRules) {
         if !self.name.serialize_renamed {
             self.name.serialize = rules.serialize.apply_to_variant(&self.name.serialize);
         }
@@ -929,8 +990,8 @@ impl Variant {
         }
     }
 
-    pub fn rename_all_rules(&self) -> &RenameAllRules {
-        &self.rename_all_rules
+    pub fn rename_all_rules(&self) -> RenameAllRules {
+        self.rename_all_rules
     }
 
     pub fn ser_bound(&self) -> Option<&[syn::WherePredicate]> {
@@ -1259,7 +1320,7 @@ impl Field {
         self.name.deserialize_aliases()
     }
 
-    pub fn rename_by_rules(&mut self, rules: &RenameAllRules) {
+    pub fn rename_by_rules(&mut self, rules: RenameAllRules) {
         if !self.name.serialize_renamed {
             self.name.serialize = rules.serialize.apply_to_field(&self.name.serialize);
         }

serde_derive/src/internals/case.rs

@@ -54,8 +54,8 @@ impl RenameRule {
     }
 
     /// Apply a renaming rule to an enum variant, returning the version expected in the source.
-    pub fn apply_to_variant(&self, variant: &str) -> String {
-        match *self {
+    pub fn apply_to_variant(self, variant: &str) -> String {
+        match self {
             None | PascalCase => variant.to_owned(),
             LowerCase => variant.to_ascii_lowercase(),
             UpperCase => variant.to_ascii_uppercase(),
@@ -79,8 +79,8 @@ impl RenameRule {
     }
 
     /// Apply a renaming rule to a struct field, returning the version expected in the source.
-    pub fn apply_to_field(&self, field: &str) -> String {
-        match *self {
+    pub fn apply_to_field(self, field: &str) -> String {
+        match self {
             None | LowerCase | SnakeCase => field.to_owned(),
             UpperCase => field.to_ascii_uppercase(),
             PascalCase => {
@@ -107,6 +107,14 @@ impl RenameRule {
             ScreamingKebabCase => ScreamingSnakeCase.apply_to_field(field).replace('_', "-"),
         }
     }
+
+    /// Returns the `RenameRule` if it is not `None`, `rule_b` otherwise.
+    pub fn or(self, rule_b: Self) -> Self {
+        match self {
+            None => rule_b,
+            _ => self,
+        }
+    }
 }
 
 pub struct ParseError<'a> {

serde_derive/src/internals/symbol.rs

@@ -23,6 +23,7 @@ pub const OTHER: Symbol = Symbol("other");
 pub const REMOTE: Symbol = Symbol("remote");
 pub const RENAME: Symbol = Symbol("rename");
 pub const RENAME_ALL: Symbol = Symbol("rename_all");
+pub const RENAME_ALL_FIELDS: Symbol = Symbol("rename_all_fields");
 pub const REPR: Symbol = Symbol("repr");
 pub const SERDE: Symbol = Symbol("serde");
 pub const SERIALIZE: Symbol = Symbol("serialize");

serde_derive/src/lib.rs

@@ -13,8 +13,7 @@
 //!
 //! [https://serde.rs/derive.html]: https://serde.rs/derive.html
 
-#![doc(html_root_url = "https://docs.rs/serde_derive/1.0.176")]
-#![allow(unknown_lints, bare_trait_objects)]
+#![doc(html_root_url = "https://docs.rs/serde_derive/1.0.180")]
 // Ignored clippy lints
 #![allow(
     // clippy false positive: https://github.com/rust-lang/rust-clippy/issues/7054
@@ -91,7 +90,6 @@ mod dummy;
 mod pretend;
 mod ser;
 mod this;
-mod try;
 
 #[cfg(precompiled)]
 macro_rules! parse_macro_input {

serde_derive/src/ser.rs

@@ -282,7 +282,7 @@ fn serialize_tuple_struct(
         .fold(quote!(0), |sum, expr| quote!(#sum + #expr));
 
     quote_block! {
-        let #let_mut __serde_state = try!(_serde::Serializer::serialize_tuple_struct(__serializer, #type_name, #len));
+        let #let_mut __serde_state = _serde::Serializer::serialize_tuple_struct(__serializer, #type_name, #len)?;
         #(#serialize_stmts)*
         _serde::ser::SerializeTupleStruct::end(__serde_state)
     }
@@ -304,7 +304,7 @@ fn serialize_struct_tag_field(cattrs: &attr::Container, struct_trait: &StructTra
             let type_name = cattrs.name().serialize_name();
             let func = struct_trait.serialize_field(Span::call_site());
             quote! {
-                try!(#func(&mut __serde_state, #tag, #type_name));
+                #func(&mut __serde_state, #tag, #type_name)?;
             }
         }
         _ => quote! {},
@@ -345,7 +345,7 @@ fn serialize_struct_as_struct(
         );
 
     quote_block! {
-        let #let_mut __serde_state = try!(_serde::Serializer::serialize_struct(__serializer, #type_name, #len));
+        let #let_mut __serde_state = _serde::Serializer::serialize_struct(__serializer, #type_name, #len)?;
         #tag_field
         #(#serialize_fields)*
         _serde::ser::SerializeStruct::end(__serde_state)
@@ -389,7 +389,7 @@ fn serialize_struct_as_map(
     };
 
     quote_block! {
-        let #let_mut __serde_state = try!(_serde::Serializer::serialize_map(__serializer, #len));
+        let #let_mut __serde_state = _serde::Serializer::serialize_map(__serializer, #len)?;
         #tag_field
         #(#serialize_fields)*
         _serde::ser::SerializeMap::end(__serde_state)
@@ -593,10 +593,10 @@ fn serialize_internally_tagged_variant(
     match effective_style(variant) {
         Style::Unit => {
             quote_block! {
-                let mut __struct = try!(_serde::Serializer::serialize_struct(
-                    __serializer, #type_name, 1));
-                try!(_serde::ser::SerializeStruct::serialize_field(
-                    &mut __struct, #tag, #variant_name));
+                let mut __struct = _serde::Serializer::serialize_struct(
+                    __serializer, #type_name, 1)?;
+                _serde::ser::SerializeStruct::serialize_field(
+                    &mut __struct, #tag, #variant_name)?;
                 _serde::ser::SerializeStruct::end(__struct)
             }
         }
@@ -650,10 +650,10 @@ fn serialize_adjacently_tagged_variant(
         match effective_style(variant) {
             Style::Unit => {
                 return quote_block! {
-                    let mut __struct = try!(_serde::Serializer::serialize_struct(
-                        __serializer, #type_name, 1));
-                    try!(_serde::ser::SerializeStruct::serialize_field(
-                        &mut __struct, #tag, #variant_name));
+                    let mut __struct = _serde::Serializer::serialize_struct(
+                        __serializer, #type_name, 1)?;
+                    _serde::ser::SerializeStruct::serialize_field(
+                        &mut __struct, #tag, #variant_name)?;
                     _serde::ser::SerializeStruct::end(__struct)
                 };
             }
@@ -667,12 +667,12 @@ fn serialize_adjacently_tagged_variant(
                 let span = field.original.span();
                 let func = quote_spanned!(span=> _serde::ser::SerializeStruct::serialize_field);
                 return quote_block! {
-                    let mut __struct = try!(_serde::Serializer::serialize_struct(
-                        __serializer, #type_name, 2));
-                    try!(_serde::ser::SerializeStruct::serialize_field(
-                        &mut __struct, #tag, #variant_name));
-                    try!(#func(
-                        &mut __struct, #content, #field_expr));
+                    let mut __struct = _serde::Serializer::serialize_struct(
+                        __serializer, #type_name, 2)?;
+                    _serde::ser::SerializeStruct::serialize_field(
+                        &mut __struct, #tag, #variant_name)?;
+                    #func(
+                        &mut __struct, #content, #field_expr)?;
                     _serde::ser::SerializeStruct::end(__struct)
                 };
             }
@@ -732,15 +732,15 @@ fn serialize_adjacently_tagged_variant(
             }
         }
 
-        let mut __struct = try!(_serde::Serializer::serialize_struct(
-            __serializer, #type_name, 2));
-        try!(_serde::ser::SerializeStruct::serialize_field(
-            &mut __struct, #tag, #variant_name));
-        try!(_serde::ser::SerializeStruct::serialize_field(
+        let mut __struct = _serde::Serializer::serialize_struct(
+            __serializer, #type_name, 2)?;
+        _serde::ser::SerializeStruct::serialize_field(
+            &mut __struct, #tag, #variant_name)?;
+        _serde::ser::SerializeStruct::serialize_field(
             &mut __struct, #content, &__AdjacentlyTagged {
                 data: (#(#fields_ident,)*),
                 phantom: _serde::__private::PhantomData::<#this_type #ty_generics>,
-            }));
+            })?;
         _serde::ser::SerializeStruct::end(__struct)
     }
 }
@@ -830,21 +830,21 @@ fn serialize_tuple_variant(
             variant_name,
         } => {
             quote_block! {
-                let #let_mut __serde_state = try!(_serde::Serializer::serialize_tuple_variant(
+                let #let_mut __serde_state = _serde::Serializer::serialize_tuple_variant(
                     __serializer,
                     #type_name,
                     #variant_index,
                     #variant_name,
-                    #len));
+                    #len)?;
                 #(#serialize_stmts)*
                 _serde::ser::SerializeTupleVariant::end(__serde_state)
             }
         }
         TupleVariant::Untagged => {
             quote_block! {
-                let #let_mut __serde_state = try!(_serde::Serializer::serialize_tuple(
+                let #let_mut __serde_state = _serde::Serializer::serialize_tuple(
                     __serializer,
-                    #len));
+                    #len)?;
                 #(#serialize_stmts)*
                 _serde::ser::SerializeTuple::end(__serde_state)
             }
@@ -907,40 +907,40 @@ fn serialize_struct_variant(
             variant_name,
         } => {
             quote_block! {
-                let #let_mut __serde_state = try!(_serde::Serializer::serialize_struct_variant(
+                let #let_mut __serde_state = _serde::Serializer::serialize_struct_variant(
                     __serializer,
                     #name,
                     #variant_index,
                     #variant_name,
                     #len,
-                ));
+                )?;
                 #(#serialize_fields)*
                 _serde::ser::SerializeStructVariant::end(__serde_state)
             }
         }
         StructVariant::InternallyTagged { tag, variant_name } => {
             quote_block! {
-                let mut __serde_state = try!(_serde::Serializer::serialize_struct(
+                let mut __serde_state = _serde::Serializer::serialize_struct(
                     __serializer,
                     #name,
                     #len + 1,
-                ));
-                try!(_serde::ser::SerializeStruct::serialize_field(
+                )?;
+                _serde::ser::SerializeStruct::serialize_field(
                     &mut __serde_state,
                     #tag,
                     #variant_name,
-                ));
+                )?;
                 #(#serialize_fields)*
                 _serde::ser::SerializeStruct::end(__serde_state)
             }
         }
         StructVariant::Untagged => {
             quote_block! {
-                let #let_mut __serde_state = try!(_serde::Serializer::serialize_struct(
+                let #let_mut __serde_state = _serde::Serializer::serialize_struct(
                     __serializer,
                     #name,
                     #len,
-                ));
+                )?;
                 #(#serialize_fields)*
                 _serde::ser::SerializeStruct::end(__serde_state)
             }
@@ -990,9 +990,9 @@ fn serialize_struct_variant_with_flatten(
                         __S: _serde::Serializer,
                     {
                         let (#(#members,)*) = self.data;
-                        let #let_mut __serde_state = try!(_serde::Serializer::serialize_map(
+                        let #let_mut __serde_state = _serde::Serializer::serialize_map(
                             __serializer,
-                            _serde::__private::None));
+                            _serde::__private::None)?;
                         #(#serialize_fields)*
                         _serde::ser::SerializeMap::end(__serde_state)
                     }
@@ -1011,23 +1011,23 @@ fn serialize_struct_variant_with_flatten(
         }
         StructVariant::InternallyTagged { tag, variant_name } => {
             quote_block! {
-                let #let_mut __serde_state = try!(_serde::Serializer::serialize_map(
+                let #let_mut __serde_state = _serde::Serializer::serialize_map(
                     __serializer,
-                    _serde::__private::None));
-                try!(_serde::ser::SerializeMap::serialize_entry(
+                    _serde::__private::None)?;
+                _serde::ser::SerializeMap::serialize_entry(
                     &mut __serde_state,
                     #tag,
                     #variant_name,
-                ));
+                )?;
                 #(#serialize_fields)*
                 _serde::ser::SerializeMap::end(__serde_state)
             }
         }
         StructVariant::Untagged => {
             quote_block! {
-                let #let_mut __serde_state = try!(_serde::Serializer::serialize_map(
+                let #let_mut __serde_state = _serde::Serializer::serialize_map(
                     __serializer,
-                    _serde::__private::None));
+                    _serde::__private::None)?;
                 #(#serialize_fields)*
                 _serde::ser::SerializeMap::end(__serde_state)
             }
@@ -1072,7 +1072,7 @@ fn serialize_tuple_struct_visitor(
             let span = field.original.span();
             let func = tuple_trait.serialize_element(span);
             let ser = quote! {
-                try!(#func(&mut __serde_state, #field_expr));
+                #func(&mut __serde_state, #field_expr)?;
             };
 
             match skip {
@@ -1116,12 +1116,12 @@ fn serialize_struct_visitor(
             let ser = if field.attrs.flatten() {
                 let func = quote_spanned!(span=> _serde::Serialize::serialize);
                 quote! {
-                    try!(#func(&#field_expr, _serde::__private::ser::FlatMapSerializer(&mut __serde_state)));
+                    #func(&#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));
+                    #func(&mut __serde_state, #key_expr, #field_expr)?;
                 }
             };
 
@@ -1133,7 +1133,7 @@ fn serialize_struct_visitor(
                             if !#skip {
                                 #ser
                             } else {
-                                try!(#skip_func(&mut __serde_state, #key_expr));
+                                #skip_func(&mut __serde_state, #key_expr)?;
                             }
                         }
                     } else {
@@ -1233,7 +1233,7 @@ fn wrap_serialize_with(
 
 // Serialization of an empty struct results in code like:
 //
-//     let mut __serde_state = try!(serializer.serialize_struct("S", 0));
+//     let mut __serde_state = serializer.serialize_struct("S", 0)?;
 //     _serde::ser::SerializeStruct::end(__serde_state)
 //
 // where we want to omit the `mut` to avoid a warning.

serde_derive/src/try.rs

@@ -1,25 +0,0 @@
-use proc_macro2::{Punct, Spacing, TokenStream};
-use quote::quote;
-
-// None of our generated code requires the `From::from` error conversion
-// performed by the standard library's `try!` macro. With this simplified macro
-// we see a significant improvement in type checking and borrow checking time of
-// the generated code and a slight improvement in binary size.
-pub fn replacement() -> TokenStream {
-    // Cannot pass `$expr` to `quote!` prior to Rust 1.17.0 so interpolate it.
-    let dollar = Punct::new('$', Spacing::Alone);
-
-    quote! {
-        #[allow(unused_macros)]
-        macro_rules! try {
-            (#dollar __expr:expr) => {
-                match #dollar __expr {
-                    _serde::__private::Ok(__val) => __val,
-                    _serde::__private::Err(__err) => {
-                        return _serde::__private::Err(__err);
-                    }
-                }
-            }
-        }
-    }
-}

serde_derive_internals/Cargo.toml

@@ -17,7 +17,7 @@ path = "lib.rs"
 [dependencies]
 proc-macro2 = "1.0"
 quote = "1.0"
-syn = { version = "2.0.25", default-features = false, features = ["clone-impls", "derive", "parsing", "printing"] }
+syn = { version = "2.0.28", default-features = false, features = ["clone-impls", "derive", "parsing", "printing"] }
 
 [package.metadata.docs.rs]
 targets = ["x86_64-unknown-linux-gnu"]

serde_derive_internals/lib.rs

@@ -1,5 +1,4 @@
 #![doc(html_root_url = "https://docs.rs/serde_derive_internals/0.28.0")]
-#![allow(unknown_lints, bare_trait_objects)]
 // Ignored clippy lints
 #![allow(
     clippy::cognitive_complexity,
@@ -30,6 +29,7 @@
     clippy::missing_errors_doc,
     clippy::module_name_repetitions,
     clippy::must_use_candidate,
+    clippy::return_self_not_must_use,
     clippy::similar_names,
     clippy::single_match_else,
     clippy::struct_excessive_bools,

test_suite/tests/test_annotations.rs

@@ -114,42 +114,6 @@ struct CollectOther {
     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(
@@ -1643,149 +1607,6 @@ fn test_collect_other() {
     );
 }
 
-#[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)]
@@ -2142,86 +1963,6 @@ fn test_lifetime_propagation_for_flatten() {
     );
 }
 
-#[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]
-fn test_flatten_internally_tagged() {
-    #[derive(Serialize, Deserialize, PartialEq, Debug)]
-    struct S {
-        #[serde(flatten)]
-        x: X,
-        #[serde(flatten)]
-        y: Y,
-    }
-
-    #[derive(Serialize, Deserialize, PartialEq, Debug)]
-    #[serde(tag = "typeX")]
-    enum X {
-        A { a: i32 },
-        B { b: i32 },
-    }
-
-    #[derive(Serialize, Deserialize, PartialEq, Debug)]
-    #[serde(tag = "typeY")]
-    enum Y {
-        C { c: i32 },
-        D { d: i32 },
-    }
-
-    let s = S {
-        x: X::B { b: 1 },
-        y: Y::D { d: 2 },
-    };
-
-    assert_tokens(
-        &s,
-        &[
-            Token::Map { len: None },
-            Token::Str("typeX"),
-            Token::Str("B"),
-            Token::Str("b"),
-            Token::I32(1),
-            Token::Str("typeY"),
-            Token::Str("D"),
-            Token::Str("d"),
-            Token::I32(2),
-            Token::MapEnd,
-        ],
-    );
-}
-
 #[test]
 fn test_externally_tagged_enum_containing_flatten() {
     #[derive(Serialize, Deserialize, PartialEq, Debug)]
@@ -2266,24 +2007,26 @@ fn test_internally_tagged_enum_with_skipped_conflict() {
     #[serde(tag = "t")]
     enum Data {
         A,
-	#[serde(skip)]
-	B {
-	    t: String
-	},
-	C {
-	    #[serde(default, skip)]
-	    t: String
-	},
+        #[serde(skip)]
+        #[allow(dead_code)]
+        B {
+            t: String,
+        },
+        C {
+            #[serde(default, skip)]
+            t: String,
+        },
     }
 
-    let _data = Data::B { t: "".to_string() };
-
-    let data = Data::C { t: "".to_string() };
+    let data = Data::C { t: String::new() };
 
     assert_tokens(
         &data,
         &[
-            Token::Struct { name: "Data", len: 1 },
+            Token::Struct {
+                name: "Data",
+                len: 1,
+            },
             Token::Str("t"),
             Token::Str("C"),
             Token::StructEnd,
@@ -2628,35 +2371,6 @@ fn test_partially_untagged_enum_desugared() {
     );
 }
 
-#[test]
-fn test_flatten_untagged_enum() {
-    #[derive(Serialize, Deserialize, PartialEq, Debug)]
-    struct Outer {
-        #[serde(flatten)]
-        inner: Inner,
-    }
-
-    #[derive(Serialize, Deserialize, PartialEq, Debug)]
-    #[serde(untagged)]
-    enum Inner {
-        Variant { a: i32 },
-    }
-
-    let data = Outer {
-        inner: Inner::Variant { a: 0 },
-    };
-
-    assert_tokens(
-        &data,
-        &[
-            Token::Map { len: None },
-            Token::Str("a"),
-            Token::I32(0),
-            Token::MapEnd,
-        ],
-    );
-}
-
 #[test]
 fn test_flatten_option() {
     #[derive(Serialize, Deserialize, PartialEq, Debug)]
@@ -2813,48 +2527,6 @@ fn test_internally_tagged_unit_enum_with_unknown_fields() {
     );
 }
 
-#[test]
-fn test_flattened_internally_tagged_unit_enum_with_unknown_fields() {
-    #[derive(Deserialize, PartialEq, Debug)]
-    struct S {
-        #[serde(flatten)]
-        x: X,
-        #[serde(flatten)]
-        y: Y,
-    }
-
-    #[derive(Deserialize, PartialEq, Debug)]
-    #[serde(tag = "typeX")]
-    enum X {
-        A,
-    }
-
-    #[derive(Deserialize, PartialEq, Debug)]
-    #[serde(tag = "typeY")]
-    enum Y {
-        B { c: u32 },
-    }
-
-    let s = S {
-        x: X::A,
-        y: Y::B { c: 0 },
-    };
-
-    assert_de_tokens(
-        &s,
-        &[
-            Token::Map { len: None },
-            Token::Str("typeX"),
-            Token::Str("A"),
-            Token::Str("typeY"),
-            Token::Str("B"),
-            Token::Str("c"),
-            Token::I32(0),
-            Token::MapEnd,
-        ],
-    );
-}
-
 #[test]
 fn test_flatten_any_after_flatten_struct() {
     #[derive(PartialEq, Debug)]
@@ -3147,3 +2819,339 @@ fn test_expecting_message_identifier_enum() {
         r#"invalid type: map, expected something strange..."#,
     );
 }
+
+mod flatten {
+    use super::*;
+
+    mod enum_ {
+        use super::*;
+
+        mod externally_tagged {
+            use super::*;
+            use std::iter::FromIterator;
+
+            #[derive(Debug, PartialEq, Serialize, Deserialize)]
+            struct Flatten {
+                #[serde(flatten)]
+                data: Enum,
+
+                #[serde(flatten)]
+                extra: HashMap<String, String>,
+            }
+
+            #[derive(Debug, PartialEq, Serialize, Deserialize)]
+            enum Enum {
+                Newtype(HashMap<String, String>),
+                Tuple(u32, u32),
+                Struct { index: u32, value: u32 },
+            }
+
+            #[test]
+            fn newtype() {
+                assert_tokens(
+                    &Flatten {
+                        data: Enum::Newtype(HashMap::from_iter([("key".into(), "value".into())])),
+                        extra: HashMap::from_iter([("extra_key".into(), "extra value".into())]),
+                    },
+                    &[
+                        Token::Map { len: None },
+                        Token::Str("Newtype"), // variant
+                        Token::Map { len: Some(1) },
+                        Token::Str("key"),
+                        Token::Str("value"),
+                        Token::MapEnd,
+                        Token::Str("extra_key"),
+                        Token::Str("extra value"),
+                        Token::MapEnd,
+                    ],
+                );
+            }
+
+            // Reaches crate::private::de::content::VariantDeserializer::tuple_variant
+            // Content::Seq case
+            // via FlatMapDeserializer::deserialize_enum
+            #[test]
+            fn tuple() {
+                assert_tokens(
+                    &Flatten {
+                        data: Enum::Tuple(0, 42),
+                        extra: HashMap::from_iter([("extra_key".into(), "extra value".into())]),
+                    },
+                    &[
+                        Token::Map { len: None },
+                        Token::Str("Tuple"), // variant
+                        Token::Seq { len: Some(2) },
+                        Token::U32(0),
+                        Token::U32(42),
+                        Token::SeqEnd,
+                        Token::Str("extra_key"),
+                        Token::Str("extra value"),
+                        Token::MapEnd,
+                    ],
+                );
+            }
+
+            // Reaches crate::private::de::content::VariantDeserializer::struct_variant
+            // Content::Seq case
+            // via FlatMapDeserializer::deserialize_enum
+            #[test]
+            fn struct_from_seq() {
+                assert_de_tokens(
+                    &Flatten {
+                        data: Enum::Struct {
+                            index: 0,
+                            value: 42,
+                        },
+                        extra: HashMap::from_iter([("extra_key".into(), "extra value".into())]),
+                    },
+                    &[
+                        Token::Map { len: None },
+                        Token::Str("Struct"), // variant
+                        Token::Seq { len: Some(2) },
+                        Token::U32(0),  // index
+                        Token::U32(42), // value
+                        Token::SeqEnd,
+                        Token::Str("extra_key"),
+                        Token::Str("extra value"),
+                        Token::MapEnd,
+                    ],
+                );
+            }
+
+            // Reaches crate::private::de::content::VariantDeserializer::struct_variant
+            // Content::Map case
+            // via FlatMapDeserializer::deserialize_enum
+            #[test]
+            fn struct_from_map() {
+                assert_tokens(
+                    &Flatten {
+                        data: Enum::Struct {
+                            index: 0,
+                            value: 42,
+                        },
+                        extra: HashMap::from_iter([("extra_key".into(), "extra value".into())]),
+                    },
+                    &[
+                        Token::Map { len: None },
+                        Token::Str("Struct"), // variant
+                        Token::Struct {
+                            len: 2,
+                            name: "Struct",
+                        },
+                        Token::Str("index"),
+                        Token::U32(0),
+                        Token::Str("value"),
+                        Token::U32(42),
+                        Token::StructEnd,
+                        Token::Str("extra_key"),
+                        Token::Str("extra value"),
+                        Token::MapEnd,
+                    ],
+                );
+            }
+        }
+
+        mod adjacently_tagged {
+            use super::*;
+
+            #[derive(Debug, PartialEq, Serialize, Deserialize)]
+            struct Flatten {
+                outer: u32,
+
+                #[serde(flatten)]
+                data: NewtypeWrapper,
+            }
+
+            #[derive(Debug, PartialEq, Serialize, Deserialize)]
+            struct NewtypeWrapper(pub Enum);
+
+            #[derive(Debug, PartialEq, Serialize, Deserialize)]
+            #[serde(tag = "tag", content = "content")]
+            enum Enum {
+                Newtype(NewtypeVariant),
+                Struct { index: u32, value: u32 },
+            }
+
+            #[derive(Debug, PartialEq, Serialize, Deserialize)]
+            struct NewtypeVariant {
+                value: u32,
+            }
+
+            #[test]
+            fn struct_() {
+                assert_tokens(
+                    &Flatten {
+                        outer: 42,
+                        data: NewtypeWrapper(Enum::Struct {
+                            index: 0,
+                            value: 42,
+                        }),
+                    },
+                    &[
+                        Token::Map { len: None },
+                        Token::Str("outer"),
+                        Token::U32(42),
+                        Token::Str("tag"),
+                        Token::Str("Struct"),
+                        Token::Str("content"),
+                        Token::Struct {
+                            len: 2,
+                            name: "Struct",
+                        },
+                        Token::Str("index"),
+                        Token::U32(0),
+                        Token::Str("value"),
+                        Token::U32(42),
+                        Token::StructEnd,
+                        Token::MapEnd,
+                    ],
+                );
+            }
+
+            #[test]
+            fn newtype() {
+                assert_tokens(
+                    &Flatten {
+                        outer: 42,
+                        data: NewtypeWrapper(Enum::Newtype(NewtypeVariant { value: 23 })),
+                    },
+                    &[
+                        Token::Map { len: None },
+                        Token::Str("outer"),
+                        Token::U32(42),
+                        Token::Str("tag"),
+                        Token::Str("Newtype"),
+                        Token::Str("content"),
+                        Token::Struct {
+                            len: 1,
+                            name: "NewtypeVariant",
+                        },
+                        Token::Str("value"),
+                        Token::U32(23),
+                        Token::StructEnd,
+                        Token::MapEnd,
+                    ],
+                );
+            }
+        }
+
+        mod internally_tagged {
+            use super::*;
+
+            #[test]
+            fn structs() {
+                #[derive(Debug, PartialEq, Serialize, Deserialize)]
+                struct Flatten {
+                    #[serde(flatten)]
+                    x: X,
+                    #[serde(flatten)]
+                    y: Y,
+                }
+
+                #[derive(Debug, PartialEq, Serialize, Deserialize)]
+                #[serde(tag = "typeX")]
+                enum X {
+                    A { a: i32 },
+                    B { b: i32 },
+                }
+
+                #[derive(Debug, PartialEq, Serialize, Deserialize)]
+                #[serde(tag = "typeY")]
+                enum Y {
+                    C { c: i32 },
+                    D { d: i32 },
+                }
+
+                assert_tokens(
+                    &Flatten {
+                        x: X::B { b: 1 },
+                        y: Y::D { d: 2 },
+                    },
+                    &[
+                        Token::Map { len: None },
+                        Token::Str("typeX"),
+                        Token::Str("B"),
+                        Token::Str("b"),
+                        Token::I32(1),
+                        Token::Str("typeY"),
+                        Token::Str("D"),
+                        Token::Str("d"),
+                        Token::I32(2),
+                        Token::MapEnd,
+                    ],
+                );
+            }
+
+            #[test]
+            fn unit_enum_with_unknown_fields() {
+                #[derive(Debug, PartialEq, Deserialize)]
+                struct Flatten {
+                    #[serde(flatten)]
+                    x: X,
+                    #[serde(flatten)]
+                    y: Y,
+                }
+
+                #[derive(Debug, PartialEq, Deserialize)]
+                #[serde(tag = "typeX")]
+                enum X {
+                    A,
+                }
+
+                #[derive(Debug, PartialEq, Deserialize)]
+                #[serde(tag = "typeY")]
+                enum Y {
+                    B { c: u32 },
+                }
+
+                assert_de_tokens(
+                    &Flatten {
+                        x: X::A,
+                        y: Y::B { c: 0 },
+                    },
+                    &[
+                        Token::Map { len: None },
+                        Token::Str("typeX"),
+                        Token::Str("A"),
+                        Token::Str("typeY"),
+                        Token::Str("B"),
+                        Token::Str("c"),
+                        Token::I32(0),
+                        Token::MapEnd,
+                    ],
+                );
+            }
+        }
+
+        mod untagged {
+            use super::*;
+
+            #[derive(Debug, PartialEq, Serialize, Deserialize)]
+            struct Flatten {
+                #[serde(flatten)]
+                data: Enum,
+            }
+
+            #[derive(Debug, PartialEq, Serialize, Deserialize)]
+            #[serde(untagged)]
+            enum Enum {
+                Struct { a: i32 },
+            }
+
+            #[test]
+            fn struct_() {
+                assert_tokens(
+                    &Flatten {
+                        data: Enum::Struct { a: 0 },
+                    },
+                    &[
+                        Token::Map { len: None },
+                        Token::Str("a"),
+                        Token::I32(0),
+                        Token::MapEnd,
+                    ],
+                );
+            }
+        }
+    }
+}

test_suite/tests/test_macros.rs

@@ -1429,6 +1429,9 @@ fn test_enum_in_internally_tagged_enum() {
         ],
     );
 
+    // Reaches crate::private::de::content::VariantDeserializer::tuple_variant
+    // Content::Seq case
+    // via ContentDeserializer::deserialize_enum
     assert_tokens(
         &Outer::Inner(Inner::Tuple(1, 1)),
         &[
@@ -1447,6 +1450,9 @@ fn test_enum_in_internally_tagged_enum() {
         ],
     );
 
+    // Reaches crate::private::de::content::VariantDeserializer::struct_variant
+    // Content::Map case
+    // via ContentDeserializer::deserialize_enum
     assert_tokens(
         &Outer::Inner(Inner::Struct { f: 1 }),
         &[
@@ -1464,6 +1470,23 @@ fn test_enum_in_internally_tagged_enum() {
             Token::MapEnd,
         ],
     );
+
+    // Reaches crate::private::de::content::VariantDeserializer::struct_variant
+    // Content::Seq case
+    // via ContentDeserializer::deserialize_enum
+    assert_de_tokens(
+        &Outer::Inner(Inner::Struct { f: 1 }),
+        &[
+            Token::Map { len: Some(2) },
+            Token::Str("type"),
+            Token::Str("Inner"),
+            Token::Str("Struct"),
+            Token::Seq { len: Some(1) },
+            Token::U8(1), // f
+            Token::SeqEnd,
+            Token::MapEnd,
+        ],
+    );
 }
 
 #[test]
@@ -1923,6 +1946,62 @@ fn test_rename_all() {
     );
 }
 
+#[test]
+fn test_rename_all_fields() {
+    #[derive(Serialize, Deserialize, Debug, PartialEq)]
+    #[serde(rename_all_fields = "kebab-case")]
+    enum E {
+        V1,
+        V2(bool),
+        V3 {
+            a_field: bool,
+            another_field: bool,
+            #[serde(rename = "last-field")]
+            yet_another_field: bool,
+        },
+        #[serde(rename_all = "snake_case")]
+        V4 {
+            a_field: bool,
+        },
+    }
+
+    assert_tokens(
+        &E::V3 {
+            a_field: true,
+            another_field: true,
+            yet_another_field: true,
+        },
+        &[
+            Token::StructVariant {
+                name: "E",
+                variant: "V3",
+                len: 3,
+            },
+            Token::Str("a-field"),
+            Token::Bool(true),
+            Token::Str("another-field"),
+            Token::Bool(true),
+            Token::Str("last-field"),
+            Token::Bool(true),
+            Token::StructVariantEnd,
+        ],
+    );
+
+    assert_tokens(
+        &E::V4 { a_field: true },
+        &[
+            Token::StructVariant {
+                name: "E",
+                variant: "V4",
+                len: 1,
+            },
+            Token::Str("a_field"),
+            Token::Bool(true),
+            Token::StructVariantEnd,
+        ],
+    );
+}
+
 #[test]
 fn test_untagged_newtype_variant_containing_unit_struct_not_map() {
     #[derive(Debug, PartialEq, Serialize, Deserialize)]

test_suite/tests/ui/default-attribute/enum.stderr

@@ -1,5 +1,5 @@
 error: #[serde(default)] can only be used on structs with named fields
- --> tests/ui/default-attribute/enum.rs:5:1
+ --> tests/ui/default-attribute/enum.rs:4:9
   |
-5 | enum E {
-  | ^^^^
+4 | #[serde(default)]
+  |         ^^^^^^^

test_suite/tests/ui/default-attribute/enum_path.stderr

@@ -1,5 +1,5 @@
 error: #[serde(default = "...")] can only be used on structs with named fields
- --> tests/ui/default-attribute/enum_path.rs:5:1
+ --> tests/ui/default-attribute/enum_path.rs:4:9
   |
-5 | enum E {
-  | ^^^^
+4 | #[serde(default = "default_e")]
+  |         ^^^^^^^^^^^^^^^^^^^^^

test_suite/tests/ui/default-attribute/nameless_struct_fields_path.stderr

@@ -1,5 +1,5 @@
 error: #[serde(default = "...")] can only be used on structs with named fields
- --> tests/ui/default-attribute/nameless_struct_fields_path.rs:5:9
+ --> tests/ui/default-attribute/nameless_struct_fields_path.rs:4:9
   |
-5 | struct T(u8, u8);
-  |         ^^^^^^^^
+4 | #[serde(default = "default_t")]
+  |         ^^^^^^^^^^^^^^^^^^^^^

test_suite/tests/ui/enum-representation/untagged-struct.stderr

@@ -1,5 +1,5 @@
 error: #[serde(untagged)] can only be used on enums
- --> tests/ui/enum-representation/untagged-struct.rs:5:1
+ --> tests/ui/enum-representation/untagged-struct.rs:4:9
   |
-5 | struct S;
-  | ^^^^^^
+4 | #[serde(untagged)]
+  |         ^^^^^^^^

test_suite/tests/ui/struct-representation/internally-tagged-tuple.stderr

@@ -1,5 +1,5 @@
 error: #[serde(tag = "...")] can only be used on enums and structs with named fields
- --> tests/ui/struct-representation/internally-tagged-tuple.rs:5:9
+ --> tests/ui/struct-representation/internally-tagged-tuple.rs:4:9
   |
-5 | struct S(u8, u8);
-  |         ^^^^^^^^
+4 | #[serde(tag = "type")]
+  |         ^^^^^^^^^^^^

test_suite/tests/ui/struct-representation/internally-tagged-unit.stderr

@@ -1,7 +1,5 @@
 error: #[serde(tag = "...")] can only be used on enums and structs with named fields
- --> tests/ui/struct-representation/internally-tagged-unit.rs:3:10
+ --> tests/ui/struct-representation/internally-tagged-unit.rs:4:9
   |
-3 | #[derive(Serialize)]
-  |          ^^^^^^^^^
-  |
-  = note: this error originates in the derive macro `Serialize` (in Nightly builds, run with -Z macro-backtrace for more info)
+4 | #[serde(tag = "type")]
+  |         ^^^^^^^^^^^^