Fix field ordering issues with #[reflect(skip_serializing)]

crates/bevy_reflect/bevy_reflect_derive/Cargo.toml

@@ -23,4 +23,3 @@ syn = { version = "2.0", features = ["full"] }
 proc-macro2 = "1.0"
 quote = "1.0"
 uuid = { version = "1.1", features = ["v4"] }
-bit-set = "0.5.2" 

crates/bevy_reflect/bevy_reflect_derive/src/associated_data.rs

@@ -0,0 +1,66 @@
+use crate::field_attributes::{DefaultBehavior, ReflectFieldAttr, ReflectIgnoreBehavior};
+use crate::fq_std::{FQBox, FQDefault};
+use crate::utility::ident_or_index;
+use proc_macro2::{Ident, TokenStream};
+use quote::{format_ident, ToTokens};
+use syn::{parse_quote, Field, ItemFn, Path};
+
+/// Associated data to generate alongside derived trait implementations.
+///
+/// It's important these are generated within the context of an [_unnamed const_]
+/// in order to avoid conflicts and keep the macro hygenic.
+///
+/// [_unnamed const_]: https://doc.rust-lang.org/stable/reference/items/constant-items.html#unnamed-constant
+pub(crate) struct AssociatedData {
+ default_fn: Option<ItemFn>,
+}
+
+impl AssociatedData {
+ /// Generates a new `AssociatedData` for a given field.
+ pub fn new(
+ field: &Field,
+ index: usize,
+ attrs: &ReflectFieldAttr,
+ qualifier: &Ident,
+ bevy_reflect_path: &Path,
+ ) -> Self {
+ let field_ident = ident_or_index(field.ident.as_ref(), index);
+ let field_ty = &field.ty;
+
+ let default_fn = match attrs.ignore {
+ ReflectIgnoreBehavior::IgnoreSerialization => {
+ let ident = format_ident!("get_default__{}__{}", qualifier, field_ident);
+ match &attrs.default {
+ DefaultBehavior::Required | DefaultBehavior::Default => Some(parse_quote! {
+ #[allow(non_snake_case)]
+ fn #ident() -> #FQBox<dyn #bevy_reflect_path::Reflect> {
+ #FQBox::new(<#field_ty as #FQDefault>::default())
+ }
+ }),
+ DefaultBehavior::Func(func) => Some(parse_quote! {
+ #[allow(non_snake_case)]
+ fn #ident() -> #FQBox<dyn #bevy_reflect_path::Reflect> {
+ #FQBox::new(#func() as #field_ty)
+ }
+ }),
+ }
+ }
+ _ => None,
+ };
+
+ Self { default_fn }
+ }
+
+ /// Returns the function used to generate a default instance of a field.
+ ///
+ /// Returns `None` if the field does not have or need such a function.
+ pub fn default_fn(&self) -> Option<&ItemFn> {
+ self.default_fn.as_ref()
+ }
+}
+
+impl ToTokens for AssociatedData {
+ fn to_tokens(&self, tokens: &mut TokenStream) {
+ self.default_fn.to_tokens(tokens);
+ }
+}

crates/bevy_reflect/bevy_reflect_derive/src/derive_data.rs

@@ -1,12 +1,13 @@
+use crate::associated_data::AssociatedData;
 use crate::container_attributes::ReflectTraits;
 use crate::field_attributes::{parse_field_attrs, ReflectFieldAttr};
 use crate::fq_std::{FQAny, FQDefault, FQSend, FQSync};
 use crate::type_path::parse_path_no_leading_colon;
-use crate::utility::{members_to_serialization_denylist, StringExpr, WhereClauseOptions};
-use bit_set::BitSet;
+use crate::utility::{StringExpr, WhereClauseOptions};
 use quote::{quote, ToTokens};
 use syn::token::Comma;
 
+use crate::serialization::SerializationDataDef;
 use crate::{
  utility, REFLECT_ATTRIBUTE_NAME, REFLECT_VALUE_ATTRIBUTE_NAME, TYPE_NAME_ATTRIBUTE_NAME,
  TYPE_PATH_ATTRIBUTE_NAME,
@@ -66,7 +67,7 @@ pub(crate) struct ReflectMeta<'a> {
 /// ```
 pub(crate) struct ReflectStruct<'a> {
  meta: ReflectMeta<'a>,
- serialization_denylist: BitSet<u32>,
+ serialization_data: Option<SerializationDataDef>,
  fields: Vec<StructField<'a>>,
 }
 
@@ -94,6 +95,8 @@ pub(crate) struct StructField<'a> {
  pub data: &'a Field,
  /// The reflection-based attributes on the field.
  pub attrs: ReflectFieldAttr,
+ /// The associated data to be generated on behalf of this field.
+ pub associated_data: AssociatedData,
  /// The index of this field within the struct.
  pub declaration_index: usize,
  /// The index of this field as seen by the reflection API.
@@ -269,12 +272,16 @@ impl<'a> ReflectDerive<'a> {
 
  return match &input.data {
  Data::Struct(data) => {
- let fields = Self::collect_struct_fields(&data.fields)?;
+ let fields = Self::collect_struct_fields(
+ &data.fields,
+ meta.type_path()
+ .get_ident()
+ .expect("structs should never be anonymous"),
+ meta.bevy_reflect_path(),
+ )?;
  let reflect_struct = ReflectStruct {
  meta,
- serialization_denylist: members_to_serialization_denylist(
- fields.iter().map(|v| v.attrs.ignore),
- ),
+ serialization_data: SerializationDataDef::new(&fields)?,
  fields,
  };
 
@@ -285,7 +292,8 @@ impl<'a> ReflectDerive<'a> {
  }
  }
  Data::Enum(data) => {
- let variants = Self::collect_enum_variants(&data.variants)?;
+ let variants =
+ Self::collect_enum_variants(&data.variants, meta.bevy_reflect_path())?;
 
  let reflect_enum = ReflectEnum { meta, variants };
  Ok(Self::Enum(reflect_enum))
@@ -307,14 +315,25 @@ impl<'a> ReflectDerive<'a> {
  }
  }
 
- fn collect_struct_fields(fields: &'a Fields) -> Result<Vec<StructField<'a>>, syn::Error> {
+ fn collect_struct_fields(
+ fields: &'a Fields,
+ qualifier: &Ident,
+ bevy_reflect_path: &Path,
+ ) -> Result<Vec<StructField<'a>>, syn::Error> {
  let mut active_index = 0;
  let sifter: utility::ResultSifter<StructField<'a>> = fields
  .iter()
  .enumerate()
  .map(
  |(declaration_index, field)| -> Result<StructField, syn::Error> {
  let attrs = parse_field_attrs(&field.attrs)?;
+ let associated_data = AssociatedData::new(
+ field,
+ declaration_index,
+ &attrs,
+ qualifier,
+ bevy_reflect_path,
+ );
 
  let reflection_index = if attrs.ignore.is_ignored() {
  None
@@ -327,6 +346,7 @@ impl<'a> ReflectDerive<'a> {
  declaration_index,
  reflection_index,
  attrs,
+ associated_data,
  data: field,
  #[cfg(feature = "documentation")]
  doc: crate::documentation::Documentation::from_attributes(&field.attrs),
@@ -343,12 +363,17 @@ impl<'a> ReflectDerive<'a> {
 
  fn collect_enum_variants(
  variants: &'a Punctuated<Variant, Comma>,
+ bevy_reflect_path: &Path,
  ) -> Result<Vec<EnumVariant<'a>>, syn::Error> {
  let sifter: utility::ResultSifter<EnumVariant<'a>> = variants
  .iter()
  .enumerate()
  .map(|(index, variant)| -> Result<EnumVariant, syn::Error> {
- let fields = Self::collect_struct_fields(&variant.fields)?;
+ let fields = Self::collect_struct_fields(
+ &variant.fields,
+ &variant.ident,
+ bevy_reflect_path,
+ )?;
 
  let fields = match variant.fields {
  Fields::Named(..) => EnumVariantFields::Named(fields),
@@ -371,6 +396,23 @@ impl<'a> ReflectDerive<'a> {
 
  sifter.finish()
  }
+
+ /// The complete set of fields in this item.
+ pub fn fields(&self) -> Box<dyn Iterator<Item = &StructField<'a>> + '_> {
+ match self {
+ ReflectDerive::Struct(reflect_struct)
+ | ReflectDerive::TupleStruct(reflect_struct)
+ | ReflectDerive::UnitStruct(reflect_struct) => Box::new(reflect_struct.fields.iter()),
+ ReflectDerive::Enum(reflect_enum) => Box::new(reflect_enum.fields()),
+ ReflectDerive::Value(_) => Box::new(core::iter::empty()),
+ }
+ }
+
+ /// Generate all [associated data](AssociatedData) into a `TokenStream`.
+ pub fn associated_data(&self) -> proc_macro2::TokenStream {
+ let associated_data = self.fields().map(|field| &field.associated_data);
+ quote!(#(#associated_data)*)
+ }
 }
 
 impl<'a> ReflectMeta<'a> {
@@ -426,12 +468,9 @@ impl<'a> ReflectStruct<'a> {
  &self.meta
  }
 
- /// Access the data about which fields should be ignored during serialization.
- ///
- /// The returned bitset is a collection of indices obtained from the [`members_to_serialization_denylist`](crate::utility::members_to_serialization_denylist) function.
- #[allow(dead_code)]
- pub fn serialization_denylist(&self) -> &BitSet<u32> {
- &self.serialization_denylist
+ /// Returns the [`SerializationDataDef`] for this struct.
+ pub fn serialization_data(&self) -> Option<&SerializationDataDef> {
+ self.serialization_data.as_ref()
  }
 
  /// Returns the `GetTypeRegistration` impl as a `TokenStream`.
@@ -444,7 +483,7 @@ impl<'a> ReflectStruct<'a> {
  crate::registration::impl_get_type_registration(
  self.meta(),
  where_clause_options,
- Some(&self.serialization_denylist),
+ self.serialization_data(),
  )
  }
 
@@ -513,6 +552,11 @@ impl<'a> ReflectEnum<'a> {
  &self.variants
  }
 
+ /// The complete set of fields in this enum.
+ pub fn fields(&self) -> impl Iterator<Item = &StructField<'a>> {
+ self.variants().iter().flat_map(|variant| variant.fields())
+ }
+
  /// Get an iterator of fields which are exposed to the reflection API
  pub fn active_fields(&self) -> impl Iterator<Item = &StructField<'a>> {
  self.variants()

crates/bevy_reflect/bevy_reflect_derive/src/impls/enums.rs

@@ -3,12 +3,11 @@ use crate::enum_utility::{get_variant_constructors, EnumVariantConstructors};
 use crate::fq_std::{FQAny, FQBox, FQOption, FQResult};
 use crate::impls::{impl_type_path, impl_typed};
 use crate::utility::extend_where_clause;
-use proc_macro::TokenStream;
 use proc_macro2::{Ident, Span};
 use quote::quote;
 use syn::Fields;
 
-pub(crate) fn impl_enum(reflect_enum: &ReflectEnum) -> TokenStream {
+pub(crate) fn impl_enum(reflect_enum: &ReflectEnum) -> proc_macro2::TokenStream {
  let bevy_reflect_path = reflect_enum.meta().bevy_reflect_path();
  let enum_path = reflect_enum.meta().type_path();
 
@@ -97,7 +96,7 @@ pub(crate) fn impl_enum(reflect_enum: &ReflectEnum) -> TokenStream {
 
  let where_reflect_clause = extend_where_clause(where_clause, &where_clause_options);
 
- TokenStream::from(quote! {
+ quote! {
  #get_type_registration_impl
 
  #typed_impl
@@ -291,7 +290,7 @@ pub(crate) fn impl_enum(reflect_enum: &ReflectEnum) -> TokenStream {
 
  #debug_fn
  }
- })
+ }
 }
 
 struct EnumImpls {
@@ -354,7 +353,11 @@ fn generate_impls(reflect_enum: &ReflectEnum, ref_index: &Ident, ref_name: &Iden
  // Ignored field
  continue;
  }
- constructor_argument.push(generate_for_field(reflect_idx, field.declaration_index, field));
+ constructor_argument.push(generate_for_field(
+ reflect_idx,
+ field.declaration_index,
+ field,
+ ));
  reflect_idx += 1;
  }
  constructor_argument

crates/bevy_reflect/bevy_reflect_derive/src/impls/structs.rs

@@ -2,11 +2,10 @@ use crate::fq_std::{FQAny, FQBox, FQDefault, FQOption, FQResult};
 use crate::impls::{impl_type_path, impl_typed};
 use crate::utility::{extend_where_clause, ident_or_index};
 use crate::ReflectStruct;
-use proc_macro::TokenStream;
 use quote::{quote, ToTokens};
 
 /// Implements `Struct`, `GetTypeRegistration`, and `Reflect` for the given derive data.
-pub(crate) fn impl_struct(reflect_struct: &ReflectStruct) -> TokenStream {
+pub(crate) fn impl_struct(reflect_struct: &ReflectStruct) -> proc_macro2::TokenStream {
  let fqoption = FQOption.into_token_stream();
 
  let bevy_reflect_path = reflect_struct.meta().bevy_reflect_path();
@@ -104,7 +103,7 @@ pub(crate) fn impl_struct(reflect_struct: &ReflectStruct) -> TokenStream {
 
  let where_reflect_clause = extend_where_clause(where_clause, &where_clause_options);
 
- TokenStream::from(quote! {
+ quote! {
  #get_type_registration_impl
 
  #typed_impl
@@ -245,5 +244,5 @@ pub(crate) fn impl_struct(reflect_struct: &ReflectStruct) -> TokenStream {
 
  #debug_fn
  }
- })
+ }
 }

crates/bevy_reflect/bevy_reflect_derive/src/impls/tuple_structs.rs

@@ -2,12 +2,11 @@ use crate::fq_std::{FQAny, FQBox, FQDefault, FQOption, FQResult};
 use crate::impls::{impl_type_path, impl_typed};
 use crate::utility::extend_where_clause;
 use crate::ReflectStruct;
-use proc_macro::TokenStream;
 use quote::{quote, ToTokens};
 use syn::{Index, Member};
 
 /// Implements `TupleStruct`, `GetTypeRegistration`, and `Reflect` for the given derive data.
-pub(crate) fn impl_tuple_struct(reflect_struct: &ReflectStruct) -> TokenStream {
+pub(crate) fn impl_tuple_struct(reflect_struct: &ReflectStruct) -> proc_macro2::TokenStream {
  let fqoption = FQOption.into_token_stream();
 
  let bevy_reflect_path = reflect_struct.meta().bevy_reflect_path();
@@ -95,7 +94,7 @@ pub(crate) fn impl_tuple_struct(reflect_struct: &ReflectStruct) -> TokenStream {
 
  let where_reflect_clause = extend_where_clause(where_clause, &where_clause_options);
 
- TokenStream::from(quote! {
+ quote! {
  #get_type_registration_impl
 
  #typed_impl
@@ -214,5 +213,5 @@ pub(crate) fn impl_tuple_struct(reflect_struct: &ReflectStruct) -> TokenStream {
 
  #debug_fn
  }
- })
+ }
 }

crates/bevy_reflect/bevy_reflect_derive/src/impls/values.rs

@@ -2,11 +2,10 @@ use crate::fq_std::{FQAny, FQBox, FQClone, FQOption, FQResult};
 use crate::impls::{impl_type_path, impl_typed};
 use crate::utility::{extend_where_clause, WhereClauseOptions};
 use crate::ReflectMeta;
-use proc_macro::TokenStream;
 use quote::quote;
 
 /// Implements `GetTypeRegistration` and `Reflect` for the given type data.
-pub(crate) fn impl_value(meta: &ReflectMeta) -> TokenStream {
+pub(crate) fn impl_value(meta: &ReflectMeta) -> proc_macro2::TokenStream {
  let bevy_reflect_path = meta.bevy_reflect_path();
  let type_path = meta.type_path();
 
@@ -38,7 +37,7 @@ pub(crate) fn impl_value(meta: &ReflectMeta) -> TokenStream {
  let where_reflect_clause = extend_where_clause(where_clause, &where_clause_options);
  let get_type_registration_impl = meta.get_type_registration(&where_clause_options);
 
- TokenStream::from(quote! {
+ quote! {
  #get_type_registration_impl
 
  #type_path_impl
@@ -125,5 +124,5 @@ pub(crate) fn impl_value(meta: &ReflectMeta) -> TokenStream {
 
  #debug_fn
  }
- })
+ }
 }