Release 1.0.149

Remove some Serialize trait bounds

.github/workflows/ci.yml

@@ -15,6 +15,7 @@ jobs:
   test:
     name: Test suite
     runs-on: ubuntu-latest
+    timeout-minutes: 45
     steps:
       - uses: actions/checkout@v3
       - uses: dtolnay/rust-toolchain@nightly
@@ -27,6 +28,7 @@ jobs:
   windows:
     name: Test suite (windows)
     runs-on: windows-latest
+    timeout-minutes: 45
     steps:
       - uses: actions/checkout@v3
       - uses: dtolnay/rust-toolchain@nightly
@@ -39,6 +41,7 @@ jobs:
       fail-fast: false
       matrix:
         rust: [stable, beta]
+    timeout-minutes: 45
     steps:
       - uses: actions/checkout@v3
       - uses: dtolnay/rust-toolchain@master
@@ -56,6 +59,7 @@ jobs:
       fail-fast: false
       matrix:
         os: [ubuntu, windows]
+    timeout-minutes: 45
     steps:
       - uses: actions/checkout@v3
       - uses: dtolnay/rust-toolchain@nightly
@@ -74,6 +78,7 @@ jobs:
   msrv:
     name: Rust 1.13.0
     runs-on: ubuntu-latest
+    timeout-minutes: 45
     steps:
       - uses: actions/checkout@v3
       - uses: dtolnay/rust-toolchain@1.13.0
@@ -95,6 +100,7 @@ jobs:
       fail-fast: false
       matrix:
         rust: [1.19.0, 1.20.0, 1.21.0, 1.25.0, 1.26.0, 1.34.0]
+    timeout-minutes: 45
     steps:
       - uses: actions/checkout@v3
       - uses: dtolnay/rust-toolchain@master
@@ -110,6 +116,7 @@ jobs:
       fail-fast: false
       matrix:
         rust: [1.27.0, 1.28.0]
+    timeout-minutes: 45
     steps:
       - uses: actions/checkout@v3
       - uses: dtolnay/rust-toolchain@master
@@ -123,6 +130,7 @@ jobs:
   derive:
     name: Rust 1.31.0
     runs-on: ubuntu-latest
+    timeout-minutes: 45
     steps:
       - uses: actions/checkout@v3
       - uses: dtolnay/rust-toolchain@1.31.0
@@ -133,6 +141,7 @@ jobs:
   alloc:
     name: Rust 1.36.0
     runs-on: ubuntu-latest
+    timeout-minutes: 45
     steps:
       - uses: actions/checkout@v3
       - uses: dtolnay/rust-toolchain@1.36.0
@@ -141,6 +150,7 @@ jobs:
   emscripten:
     name: Emscripten
     runs-on: ubuntu-latest
+    timeout-minutes: 45
     steps:
       - uses: actions/checkout@v3
       - uses: dtolnay/rust-toolchain@nightly
@@ -164,19 +174,21 @@ jobs:
     name: Clippy
     runs-on: ubuntu-latest
     if: github.event_name != 'pull_request'
+    timeout-minutes: 45
     steps:
       - uses: actions/checkout@v3
       - uses: dtolnay/rust-toolchain@clippy
-      - run: cd serde && cargo clippy --features rc,unstable -- -Dclippy::all -Dclippy::pedantic -Aclippy::let_underscore_drop
+      - run: cd serde && cargo clippy --features rc,unstable -- -Dclippy::all -Dclippy::pedantic
       - run: cd serde_derive && cargo clippy -- -Dclippy::all -Dclippy::pedantic
       - run: cd serde_derive_internals && cargo clippy -- -Dclippy::all -Dclippy::pedantic
-      - run: cd serde_test && cargo clippy -- -Dclippy::all -Dclippy::pedantic -Aclippy::let_underscore_drop
-      - run: cd test_suite && cargo clippy --tests --features unstable -- -Dclippy::all -Dclippy::pedantic -Aclippy::let_underscore_drop
+      - run: cd serde_test && cargo clippy -- -Dclippy::all -Dclippy::pedantic
+      - run: cd test_suite && cargo clippy --tests --features unstable -- -Dclippy::all -Dclippy::pedantic
       - run: cd test_suite/no_std && cargo clippy -- -Dclippy::all -Dclippy::pedantic
 
   miri:
     name: Miri
     runs-on: ubuntu-latest
+    timeout-minutes: 45
     steps:
       - uses: actions/checkout@v3
       - uses: dtolnay/rust-toolchain@miri
@@ -191,6 +203,7 @@ jobs:
     name: Outdated
     runs-on: ubuntu-latest
     if: github.event_name != 'pull_request'
+    timeout-minutes: 45
     steps:
       - uses: actions/checkout@v3
       - uses: dtolnay/install@cargo-outdated

serde/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "serde"
-version = "1.0.146" # remember to update html_root_url and serde_derive dependency
+version = "1.0.149" # remember to update html_root_url and serde_derive dependency
 authors = ["Erick Tryzelaar <erick.tryzelaar@gmail.com>", "David Tolnay <dtolnay@gmail.com>"]
 build = "build.rs"
 categories = ["encoding", "no-std"]
@@ -15,7 +15,7 @@ repository = "https://github.com/serde-rs/serde"
 rust-version = "1.13"
 
 [dependencies]
-serde_derive = { version = "=1.0.146", optional = true, path = "../serde_derive" }
+serde_derive = { version = "=1.0.149", optional = true, path = "../serde_derive" }
 
 [dev-dependencies]
 serde_derive = { version = "1.0", path = "../serde_derive" }

serde/build.rs

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

serde/src/de/format.rs

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

serde/src/de/value.rs

@@ -1510,6 +1510,41 @@ where
 
 ////////////////////////////////////////////////////////////////////////////////
 
+/// A deserializer holding an `EnumAccess`.
+#[derive(Clone, Debug)]
+pub struct EnumAccessDeserializer<A> {
+    access: A,
+}
+
+impl<A> EnumAccessDeserializer<A> {
+    /// Construct a new `EnumAccessDeserializer<A>`.
+    pub fn new(access: A) -> Self {
+        EnumAccessDeserializer { access: access }
+    }
+}
+
+impl<'de, A> de::Deserializer<'de> for EnumAccessDeserializer<A>
+where
+    A: de::EnumAccess<'de>,
+{
+    type Error = A::Error;
+
+    fn deserialize_any<V>(self, visitor: V) -> Result<V::Value, Self::Error>
+    where
+        V: de::Visitor<'de>,
+    {
+        visitor.visit_enum(self.access)
+    }
+
+    forward_to_deserialize_any! {
+        bool i8 i16 i32 i64 i128 u8 u16 u32 u64 u128 f32 f64 char str string
+        bytes byte_buf option unit unit_struct newtype_struct seq tuple
+        tuple_struct map struct enum identifier ignored_any
+    }
+}
+
+////////////////////////////////////////////////////////////////////////////////
+
 mod private {
     use lib::*;
 

serde/src/lib.rs

@@ -61,7 +61,7 @@
 //! [CBOR]: https://github.com/enarx/ciborium
 //! [YAML]: https://github.com/dtolnay/serde-yaml
 //! [MessagePack]: https://github.com/3Hren/msgpack-rust
-//! [TOML]: https://github.com/alexcrichton/toml-rs
+//! [TOML]: https://docs.rs/toml
 //! [Pickle]: https://github.com/birkenfeld/serde-pickle
 //! [RON]: https://github.com/ron-rs/ron
 //! [BSON]: https://github.com/mongodb/bson-rust
@@ -81,7 +81,7 @@
 ////////////////////////////////////////////////////////////////////////////////
 
 // Serde types in rustdoc of other crates get linked to here.
-#![doc(html_root_url = "https://docs.rs/serde/1.0.146")]
+#![doc(html_root_url = "https://docs.rs/serde/1.0.149")]
 // Support using Serde without the standard library!
 #![cfg_attr(not(feature = "std"), no_std)]
 // Unstable functionality only if the user asks for it. For tracking and
@@ -118,7 +118,6 @@
         derive_partial_eq_without_eq,
         enum_glob_use,
         explicit_auto_deref,
-        let_underscore_drop,
         map_err_ignore,
         new_without_default,
         result_unit_err,

serde/src/private/de.rs

@@ -1810,7 +1810,7 @@ mod content {
         V: Visitor<'de>,
         E: de::Error,
     {
-        let map = content.iter().map(|&(ref k, ref v)| {
+        let map = content.iter().map(|(k, v)| {
             (
                 ContentRefDeserializer::new(k),
                 ContentRefDeserializer::new(v),
@@ -2107,7 +2107,7 @@ mod content {
             let (variant, value) = match *self.content {
                 Content::Map(ref value) => {
                     let mut iter = value.iter();
-                    let &(ref variant, ref value) = match iter.next() {
+                    let (variant, value) = match iter.next() {
                         Some(v) => v,
                         None => {
                             return Err(de::Error::invalid_value(
@@ -2254,7 +2254,7 @@ mod content {
             V: de::Visitor<'de>,
         {
             match self.value {
-                Some(&Content::Seq(ref v)) => {
+                Some(Content::Seq(v)) => {
                     de::Deserializer::deserialize_any(SeqRefDeserializer::new(v), visitor)
                 }
                 Some(other) => Err(de::Error::invalid_type(
@@ -2277,10 +2277,10 @@ mod content {
             V: de::Visitor<'de>,
         {
             match self.value {
-                Some(&Content::Map(ref v)) => {
+                Some(Content::Map(v)) => {
                     de::Deserializer::deserialize_any(MapRefDeserializer::new(v), visitor)
                 }
-                Some(&Content::Seq(ref v)) => {
+                Some(Content::Seq(v)) => {
                     de::Deserializer::deserialize_any(SeqRefDeserializer::new(v), visitor)
                 }
                 Some(other) => Err(de::Error::invalid_type(
@@ -2403,7 +2403,7 @@ mod content {
             T: de::DeserializeSeed<'de>,
         {
             match self.iter.next() {
-                Some(&(ref key, ref value)) => {
+                Some((key, value)) => {
                     self.value = Some(value);
                     seed.deserialize(ContentRefDeserializer::new(key)).map(Some)
                 }

serde/src/private/ser.rs

@@ -525,7 +525,7 @@ mod content {
                 Content::Map(ref entries) => {
                     use ser::SerializeMap;
                     let mut map = try!(serializer.serialize_map(Some(entries.len())));
-                    for &(ref k, ref v) in entries {
+                    for (k, v) in entries {
                         try!(map.serialize_entry(k, v));
                     }
                     map.end()

serde/src/ser/impls.rs

@@ -182,7 +182,25 @@ where
     }
 }
 
-#[cfg(any(feature = "std", feature = "alloc"))]
+#[cfg(all(any(feature = "std", feature = "alloc"), not(no_relaxed_trait_bounds)))]
+macro_rules! seq_impl {
+    ($ty:ident < T $(: $tbound1:ident $(+ $tbound2:ident)*)* $(, $typaram:ident : $bound:ident)* >) => {
+        impl<T $(, $typaram)*> Serialize for $ty<T $(, $typaram)*>
+        where
+            T: Serialize,
+        {
+            #[inline]
+            fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
+            where
+                S: Serializer,
+            {
+                serializer.collect_seq(self)
+            }
+        }
+    }
+}
+
+#[cfg(all(any(feature = "std", feature = "alloc"), no_relaxed_trait_bounds))]
 macro_rules! seq_impl {
     ($ty:ident < T $(: $tbound1:ident $(+ $tbound2:ident)*)* $(, $typaram:ident : $bound:ident)* >) => {
         impl<T $(, $typaram)*> Serialize for $ty<T $(, $typaram)*>
@@ -736,8 +754,9 @@ impl Serialize for net::Ipv4Addr {
                 // Skip over delimiters that we initialized buf with
                 written += format_u8(*oct, &mut buf[written + 1..]) + 1;
             }
-            // We've only written ASCII bytes to the buffer, so it is valid UTF-8
-            serializer.serialize_str(unsafe { str::from_utf8_unchecked(&buf[..written]) })
+            // Safety: We've only written ASCII bytes to the buffer, so it is valid UTF-8
+            let buf = unsafe { str::from_utf8_unchecked(&buf[..written]) };
+            serializer.serialize_str(buf)
         } else {
             self.octets().serialize(serializer)
         }

serde_derive/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "serde_derive"
-version = "1.0.146" # remember to update html_root_url
+version = "1.0.149" # remember to update html_root_url
 authors = ["Erick Tryzelaar <erick.tryzelaar@gmail.com>", "David Tolnay <dtolnay@gmail.com>"]
 categories = ["no-std"]
 description = "Macros 1.1 implementation of #[derive(Serialize, Deserialize)]"
@@ -24,7 +24,7 @@ proc-macro = true
 [dependencies]
 proc-macro2 = "1.0"
 quote = "1.0"
-syn = "1.0.90"
+syn = "1.0.104"
 
 [dev-dependencies]
 serde = { version = "1.0", path = "../serde" }

serde_derive/src/de.rs

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

serde_derive/src/internals/check.rs

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

serde_derive/src/lib.rs

@@ -13,7 +13,7 @@
 //!
 //! [https://serde.rs/derive.html]: https://serde.rs/derive.html
 
-#![doc(html_root_url = "https://docs.rs/serde_derive/1.0.146")]
+#![doc(html_root_url = "https://docs.rs/serde_derive/1.0.149")]
 #![allow(unknown_lints, bare_trait_objects)]
 // Ignored clippy lints
 #![allow(
@@ -43,7 +43,6 @@
     clippy::enum_glob_use,
     clippy::indexing_slicing,
     clippy::items_after_statements,
-    clippy::let_underscore_drop,
     clippy::manual_assert,
     clippy::map_err_ignore,
     clippy::match_same_arms,
@@ -85,6 +84,7 @@ mod de;
 mod dummy;
 mod pretend;
 mod ser;
+mod this;
 mod try;
 
 #[proc_macro_derive(Serialize, attributes(serde))]

serde_derive/src/ser.rs

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

serde_derive/src/this.rs

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

serde_derive_internals/Cargo.toml

@@ -17,7 +17,7 @@ path = "lib.rs"
 [dependencies]
 proc-macro2 = "1.0"
 quote = "1.0"
-syn = { version = "1.0.90", default-features = false, features = ["derive", "parsing", "printing", "clone-impls"] }
+syn = { version = "1.0.104", default-features = false, features = ["derive", "parsing", "printing", "clone-impls"] }
 
 [package.metadata.docs.rs]
 targets = ["x86_64-unknown-linux-gnu"]

serde_derive_internals/lib.rs

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

serde_test/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "serde_test"
-version = "1.0.146" # remember to update html_root_url
+version = "1.0.149" # remember to update html_root_url
 authors = ["Erick Tryzelaar <erick.tryzelaar@gmail.com>", "David Tolnay <dtolnay@gmail.com>"]
 build = "build.rs"
 categories = ["development-tools::testing"]

serde_test/src/lib.rs

@@ -144,7 +144,7 @@
 //! # }
 //! ```
 
-#![doc(html_root_url = "https://docs.rs/serde_test/1.0.146")]
+#![doc(html_root_url = "https://docs.rs/serde_test/1.0.149")]
 #![cfg_attr(feature = "cargo-clippy", allow(renamed_and_removed_lints))]
 // Ignored clippy lints
 #![cfg_attr(feature = "cargo-clippy", allow(float_cmp, needless_doctest_main))]

test_suite/tests/test_annotations.rs

@@ -1244,22 +1244,17 @@ where
 {
     let s = String::deserialize(deserializer)?;
     let mut pieces = s.split(';');
-    let f1 = match pieces.next() {
-        Some(x) => x,
-        None => return Err(de::Error::invalid_length(0, &"2")),
+    let Some(f1) = pieces.next() else {
+        return Err(de::Error::invalid_length(0, &"2"));
     };
-    let f2 = match pieces.next() {
-        Some(x) => x,
-        None => return Err(de::Error::invalid_length(1, &"2")),
+    let Some(f2) = pieces.next() else {
+        return Err(de::Error::invalid_length(1, &"2"));
     };
-    let f2 = match f2.parse() {
-        Ok(n) => n,
-        Err(_) => {
-            return Err(de::Error::invalid_value(
-                Unexpected::Str(f2),
-                &"an 8-bit signed integer",
-            ));
-        }
+    let Ok(f2) = f2.parse() else {
+        return Err(de::Error::invalid_value(
+            Unexpected::Str(f2),
+            &"an 8-bit signed integer",
+        ));
     };
     Ok((f1.into(), f2))
 }

test_suite/tests/test_remote.rs

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

test_suite/tests/ui/remote/double_generic.rs

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

test_suite/tests/ui/remote/double_generic.stderr

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