Release 1.0.87

Fixed #1468, flattened struct fields made structs ignore their tag

serde/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "serde"
-version = "1.0.86" # remember to update html_root_url
+version = "1.0.87" # remember to update html_root_url
 authors = ["Erick Tryzelaar <erick.tryzelaar@gmail.com>", "David Tolnay <dtolnay@gmail.com>"]
 license = "MIT/Apache-2.0"
 description = "A generic serialization/deserialization framework"

serde/src/lib.rs

@@ -75,7 +75,7 @@
 ////////////////////////////////////////////////////////////////////////////////
 
 // Serde types in rustdoc of other crates get linked to here.
-#![doc(html_root_url = "https://docs.rs/serde/1.0.86")]
+#![doc(html_root_url = "https://docs.rs/serde/1.0.87")]
 // 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

serde_derive/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "serde_derive"
-version = "1.0.86" # remember to update html_root_url
+version = "1.0.87" # remember to update html_root_url
 authors = ["Erick Tryzelaar <erick.tryzelaar@gmail.com>", "David Tolnay <dtolnay@gmail.com>"]
 license = "MIT/Apache-2.0"
 description = "Macros 1.1 implementation of #[derive(Serialize, Deserialize)]"

serde_derive/src/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/1.0.86")]
+#![doc(html_root_url = "https://docs.rs/serde_derive/1.0.87")]
 #![cfg_attr(feature = "cargo-clippy", allow(renamed_and_removed_lints))]
 #![cfg_attr(feature = "cargo-clippy", deny(clippy, clippy_pedantic))]
 // Ignored clippy lints

serde_derive/src/ser.rs

@@ -289,37 +289,38 @@ fn serialize_struct(params: &Parameters, fields: &[Field], cattrs: &attr::Contai
     }
 }
 
+fn serialize_struct_tag_field(cattrs: &attr::Container, struct_trait: &StructTrait) -> TokenStream {
+    match *cattrs.tag() {
+        attr::TagType::Internal { ref tag } => {
+            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));
+            }
+        }
+        _ => quote! {},
+    }
+}
+
 fn serialize_struct_as_struct(
     params: &Parameters,
     fields: &[Field],
     cattrs: &attr::Container,
 ) -> Fragment {
-    let mut serialize_fields =
+    let serialize_fields =
         serialize_struct_visitor(fields, params, false, &StructTrait::SerializeStruct);
 
     let type_name = cattrs.name().serialize_name();
 
-    let additional_field_count: usize = match *cattrs.tag() {
-        attr::TagType::Internal { ref tag } => {
-            let func = StructTrait::SerializeStruct.serialize_field(Span::call_site());
-            serialize_fields.insert(
-                0,
-                quote! {
-                    try!(#func(&mut __serde_state, #tag, #type_name));
-                },
-            );
-
-            1
-        }
-        _ => 0,
-    };
+    let tag_field = serialize_struct_tag_field(cattrs, &StructTrait::SerializeStruct);
+    let tag_field_exists = !tag_field.is_empty();
 
     let mut serialized_fields = fields
         .iter()
         .filter(|&field| !field.attrs.skip_serializing())
         .peekable();
 
-    let let_mut = mut_if(serialized_fields.peek().is_some() || additional_field_count > 0);
+    let let_mut = mut_if(serialized_fields.peek().is_some() || tag_field_exists);
 
     let len = serialized_fields
         .map(|field| match field.attrs.skip_serializing_if() {
@@ -330,12 +331,13 @@ fn serialize_struct_as_struct(
             }
         })
         .fold(
-            quote!(#additional_field_count),
+            quote!(#tag_field_exists as usize),
             |sum, expr| quote!(#sum + #expr),
         );
 
     quote_block! {
         let #let_mut __serde_state = try!(_serde::Serializer::serialize_struct(__serializer, #type_name, #len));
+        #tag_field
         #(#serialize_fields)*
         _serde::ser::SerializeStruct::end(__serde_state)
     }
@@ -349,12 +351,15 @@ fn serialize_struct_as_map(
     let serialize_fields =
         serialize_struct_visitor(fields, params, false, &StructTrait::SerializeMap);
 
+    let tag_field = serialize_struct_tag_field(cattrs, &StructTrait::SerializeMap);
+    let tag_field_exists = !tag_field.is_empty();
+
     let mut serialized_fields = fields
         .iter()
         .filter(|&field| !field.attrs.skip_serializing())
         .peekable();
 
-    let let_mut = mut_if(serialized_fields.peek().is_some());
+    let let_mut = mut_if(serialized_fields.peek().is_some() || tag_field_exists);
 
     let len = if cattrs.has_flatten() {
         quote!(_serde::export::None)
@@ -367,12 +372,16 @@ fn serialize_struct_as_map(
                     quote!(if #path(#field_expr) { 0 } else { 1 })
                 }
             })
-            .fold(quote!(0), |sum, expr| quote!(#sum + #expr));
+            .fold(
+                quote!(#tag_field_exists as usize),
+                |sum, expr| quote!(#sum + #expr),
+            );
         quote!(_serde::export::Some(#len))
     };
 
     quote_block! {
         let #let_mut __serde_state = try!(_serde::Serializer::serialize_map(__serializer, #len));
+        #tag_field
         #(#serialize_fields)*
         _serde::ser::SerializeMap::end(__serde_state)
     }

serde_test/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "serde_test"
-version = "1.0.86" # remember to update html_root_url
+version = "1.0.87" # remember to update html_root_url
 authors = ["Erick Tryzelaar <erick.tryzelaar@gmail.com>", "David Tolnay <dtolnay@gmail.com>"]
 license = "MIT/Apache-2.0"
 description = "Token De/Serializer for testing De/Serialize implementations"

serde_test/src/lib.rs

@@ -144,7 +144,7 @@
 //! # }
 //! ```
 
-#![doc(html_root_url = "https://docs.rs/serde_test/1.0.86")]
+#![doc(html_root_url = "https://docs.rs/serde_test/1.0.87")]
 #![cfg_attr(feature = "cargo-clippy", allow(renamed_and_removed_lints))]
 #![cfg_attr(feature = "cargo-clippy", deny(clippy, clippy_pedantic))]
 // Ignored clippy lints

test_suite/tests/test_macros.rs

@@ -1424,6 +1424,48 @@ fn test_internally_tagged_braced_struct_with_zero_fields() {
     );
 }
 
+#[test]
+fn test_internally_tagged_struct_with_flattened_field() {
+    #[derive(Debug, PartialEq, Serialize, Deserialize)]
+    #[serde(tag = "tag_struct")]
+    pub struct Struct {
+        #[serde(flatten)]
+        pub flat: Enum,
+    }
+
+    #[derive(Debug, PartialEq, Serialize, Deserialize)]
+    #[serde(tag = "tag_enum", content = "content")]
+    pub enum Enum {
+        A(u64),
+    }
+
+    assert_tokens(
+        &Struct { flat: Enum::A(0) },
+        &[
+            Token::Map { len: None },
+            Token::Str("tag_struct"),
+            Token::Str("Struct"),
+            Token::Str("tag_enum"),
+            Token::Str("A"),
+            Token::Str("content"),
+            Token::U64(0),
+            Token::MapEnd,
+        ],
+    );
+
+    assert_de_tokens(
+        &Struct { flat: Enum::A(0) },
+        &[
+            Token::Map { len: None },
+            Token::Str("tag_enum"),
+            Token::Str("A"),
+            Token::Str("content"),
+            Token::U64(0),
+            Token::MapEnd,
+        ],
+    );
+}
+
 #[test]
 fn test_enum_in_untagged_enum() {
     #[derive(Debug, PartialEq, Serialize, Deserialize)]