darkfi-derive-internal: Add support for Async{Encodable,Decodable} derive.

src/serial/derive-internal/Cargo.toml

@@ -12,3 +12,7 @@ edition = "2021"
 proc-macro2 = "1.0.66"
 quote = "1.0.33"
 syn = {version = "2.0.29", features = ["full", "fold"]}
+
+[features]
+default = []
+async = []

src/serial/derive-internal/src/async_derive.rs

@@ -0,0 +1,412 @@
+/* This file is part of DarkFi (https://dark.fi)
+ *
+ * Copyright (C) 2020-2023 Dyne.org foundation
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+//! Derive (de)serialization for enums and structs, see src/serial/derive
+use proc_macro2::{Ident, Span, TokenStream};
+use quote::quote;
+use syn::{
+    Fields, FieldsNamed, FieldsUnnamed, Index, ItemEnum, ItemStruct, WhereClause, WherePredicate,
+};
+
+use super::{contains_initialize_with, contains_skip, discriminant_map, VariantParts};
+
+fn named_fields(
+    cratename: &Ident,
+    enum_ident: &Ident,
+    variant_ident: &Ident,
+    discriminant_value: &TokenStream,
+    fields: &FieldsNamed,
+) -> syn::Result<VariantParts> {
+    let mut where_predicates: Vec<WherePredicate> = vec![];
+    let mut variant_header = TokenStream::new();
+    let mut variant_body = TokenStream::new();
+
+    for field in &fields.named {
+        if !contains_skip(&field.attrs) {
+            let field_ident = field.ident.clone().unwrap();
+
+            variant_header.extend(quote! { #field_ident, });
+
+            let field_type = &field.ty;
+            where_predicates.push(
+                syn::parse2(quote! {
+                    #field_type: #cratename::AsyncEncodable
+                })
+                .unwrap(),
+            );
+
+            variant_body.extend(quote! {
+                len += #field_ident.encode_async(s).await?;
+            })
+        }
+    }
+
+    // `..` pattern matching works even if all fields were specified
+    variant_header = quote! { { #variant_header .. }};
+    let variant_idx_body = quote!(
+        #enum_ident::#variant_ident { .. } => #discriminant_value,
+    );
+
+    Ok(VariantParts { where_predicates, variant_header, variant_body, variant_idx_body })
+}
+
+fn unnamed_fields(
+    cratename: &Ident,
+    enum_ident: &Ident,
+    variant_ident: &Ident,
+    discriminant_value: &TokenStream,
+    fields: &FieldsUnnamed,
+) -> syn::Result<VariantParts> {
+    let mut where_predicates: Vec<WherePredicate> = vec![];
+    let mut variant_header = TokenStream::new();
+    let mut variant_body = TokenStream::new();
+
+    for (field_idx, field) in fields.unnamed.iter().enumerate() {
+        let field_idx = u32::try_from(field_idx).expect("up to 2^32 fields are supported");
+        if contains_skip(&field.attrs) {
+            let field_ident = Ident::new(format!("_id{}", field_idx).as_str(), Span::mixed_site());
+            variant_header.extend(quote! { #field_ident, });
+        } else {
+            let field_ident = Ident::new(format!("id{}", field_idx).as_str(), Span::mixed_site());
+            variant_header.extend(quote! { #field_ident, });
+
+            let field_type = &field.ty;
+            where_predicates.push(
+                syn::parse2(quote! {
+                    #field_type: #cratename::AsyncEncodable
+                })
+                .unwrap(),
+            );
+
+            variant_body.extend(quote! {
+                len += #field_ident.encode_async(s).await?;
+            })
+        }
+    }
+
+    variant_header = quote! { ( #variant_header )};
+    let variant_idx_body = quote!(
+        #enum_ident::#variant_ident(..) => #discriminant_value,
+    );
+
+    Ok(VariantParts { where_predicates, variant_header, variant_body, variant_idx_body })
+}
+
+pub fn async_enum_ser(input: &ItemEnum, cratename: Ident) -> syn::Result<TokenStream> {
+    let enum_ident = &input.ident;
+    let (impl_generics, ty_generics, where_clause) = input.generics.split_for_impl();
+    let mut where_clause = where_clause.map_or_else(
+        || WhereClause { where_token: Default::default(), predicates: Default::default() },
+        Clone::clone,
+    );
+    let mut all_variants_idx_body = TokenStream::new();
+    let mut fields_body = TokenStream::new();
+    let discriminants = discriminant_map(&input.variants);
+
+    for variant in input.variants.iter() {
+        let variant_ident = &variant.ident;
+        let discriminant_value = discriminants.get(variant_ident).unwrap();
+        let VariantParts { where_predicates, variant_header, variant_body, variant_idx_body } =
+            match &variant.fields {
+                Fields::Named(fields) => {
+                    named_fields(&cratename, enum_ident, variant_ident, discriminant_value, fields)?
+                }
+                Fields::Unnamed(fields) => unnamed_fields(
+                    &cratename,
+                    enum_ident,
+                    variant_ident,
+                    discriminant_value,
+                    fields,
+                )?,
+                Fields::Unit => {
+                    let variant_idx_body = quote!(
+                        #enum_ident::#variant_ident => #discriminant_value,
+                    );
+                    VariantParts {
+                        where_predicates: vec![],
+                        variant_header: TokenStream::new(),
+                        variant_body: TokenStream::new(),
+                        variant_idx_body,
+                    }
+                }
+            };
+        where_predicates.into_iter().for_each(|predicate| where_clause.predicates.push(predicate));
+        all_variants_idx_body.extend(variant_idx_body);
+        fields_body.extend(quote!(
+            #enum_ident::#variant_ident #variant_header => {
+                #variant_body
+            }
+        ))
+    }
+
+    Ok(quote! {
+    #[async_trait]
+    impl #impl_generics #cratename::AsyncEncodable for #enum_ident #ty_generics #where_clause {
+        async fn encode_async<S: AsyncWrite + Unpin + Send>(&self, s: &mut S) -> ::std::io::Result<usize> {
+            let variant_idx: u8 = match self {
+                #all_variants_idx_body
+            };
+
+            let mut len = 0;
+            let bytes = variant_idx.to_le_bytes();
+            s.write_all(&bytes).await?;
+            len += bytes.len();
+
+            match self {
+                #fields_body
+            }
+
+            Ok(len)
+        }
+    }
+    })
+}
+
+pub fn async_enum_de(input: &ItemEnum, cratename: Ident) -> syn::Result<TokenStream> {
+    let name = &input.ident;
+    let (impl_generics, ty_generics, where_clause) = input.generics.split_for_impl();
+    let mut where_clause = where_clause.map_or_else(
+        || WhereClause { where_token: Default::default(), predicates: Default::default() },
+        Clone::clone,
+    );
+
+    let init_method = contains_initialize_with(&input.attrs);
+    let mut variant_arms = TokenStream::new();
+    let discriminants = discriminant_map(&input.variants);
+
+    for variant in input.variants.iter() {
+        let variant_ident = &variant.ident;
+        let discriminant = discriminants.get(variant_ident).unwrap();
+        let mut variant_header = TokenStream::new();
+        match &variant.fields {
+            Fields::Named(fields) => {
+                for field in &fields.named {
+                    let field_name = field.ident.as_ref().unwrap();
+                    if contains_skip(&field.attrs) {
+                        variant_header.extend(quote! {
+                            #field_name: Default::default(),
+                        });
+                    } else {
+                        let field_type = &field.ty;
+                        where_clause.predicates.push(
+                            syn::parse2(quote! {
+                                #field_type: #cratename::AsyncDecodable
+                            })
+                            .unwrap(),
+                        );
+
+                        variant_header.extend(quote! {
+                            #field_name: #cratename::AsyncDecodable::decode_async(d).await?,
+                        });
+                    }
+                }
+                variant_header = quote! { { #variant_header }};
+            }
+            Fields::Unnamed(fields) => {
+                for field in fields.unnamed.iter() {
+                    if contains_skip(&field.attrs) {
+                        variant_header.extend(quote! { Default::default(), });
+                    } else {
+                        let field_type = &field.ty;
+                        where_clause.predicates.push(
+                            syn::parse2(quote! {
+                                #field_type: #cratename::AsyncDecodable
+                            })
+                            .unwrap(),
+                        );
+
+                        variant_header.extend(quote! {
+                            #cratename::AsyncDecodable::decode_async(d).await?,
+                        });
+                    }
+                }
+                variant_header = quote! { ( #variant_header )};
+            }
+            Fields::Unit => {}
+        }
+        variant_arms.extend(quote! {
+            if variant_tag == #discriminant { #name::#variant_ident #variant_header } else
+        });
+    }
+
+    let init = if let Some(method_ident) = init_method {
+        quote! {
+            return_value.#method_ident();
+        }
+    } else {
+        quote! {}
+    };
+
+    Ok(quote! {
+    #[async_trait]
+    impl #impl_generics #cratename::AsyncDecodable for #name #ty_generics #where_clause {
+        async fn decode_async<D: AsyncRead + Unpin + Send>(d: &mut D) -> ::std::io::Result<Self> {
+            let variant_tag: u8 = #cratename::AsyncDecodable::decode_async(d).await?;
+
+            let mut return_value =
+                #variant_arms {
+                    return Err(std::io::Error::new(
+                        std::io::ErrorKind::InvalidData,
+                        format!("Unexpected variant tag: {:?}", variant_tag),
+                    ))
+                };
+                #init
+                Ok(return_value)
+            }
+        }
+    })
+}
+
+pub fn async_struct_ser(input: &ItemStruct, cratename: Ident) -> syn::Result<TokenStream> {
+    let name = &input.ident;
+    let (impl_generics, ty_generics, where_clause) = input.generics.split_for_impl();
+    let mut where_clause = where_clause.map_or_else(
+        || WhereClause { where_token: Default::default(), predicates: Default::default() },
+        Clone::clone,
+    );
+
+    let mut body = TokenStream::new();
+
+    match &input.fields {
+        Fields::Named(fields) => {
+            for field in &fields.named {
+                if contains_skip(&field.attrs) {
+                    continue
+                }
+
+                let field_name = field.ident.as_ref().unwrap();
+                let delta = quote! {
+                    len += self.#field_name.encode_async(s).await?;
+                };
+                body.extend(delta);
+
+                let field_type = &field.ty;
+                where_clause.predicates.push(
+                    syn::parse2(quote! {
+                        #field_type: #cratename::AsyncEncodable
+                    })
+                    .unwrap(),
+                );
+            }
+        }
+        Fields::Unnamed(fields) => {
+            for field_idx in 0..fields.unnamed.len() {
+                let field_idx = Index {
+                    index: u32::try_from(field_idx).expect("up to 2^32 fields are supported"),
+                    span: Span::call_site(),
+                };
+                let delta = quote! {
+                    len += self.#field_idx.encode_async(s).await?;
+                };
+                body.extend(delta);
+            }
+        }
+        Fields::Unit => {}
+    }
+
+    Ok(quote! {
+    #[async_trait]
+    impl #impl_generics #cratename::AsyncEncodable for #name #ty_generics #where_clause {
+        async fn encode_async<S: AsyncWrite + Unpin + Send>(&self, s: &mut S) -> ::std::io::Result<usize> {
+            let mut len = 0;
+            #body
+            Ok(len)
+        }
+    }
+    })
+}
+
+pub fn async_struct_de(input: &ItemStruct, cratename: Ident) -> syn::Result<TokenStream> {
+    let name = &input.ident;
+    let (impl_generics, ty_generics, where_clause) = input.generics.split_for_impl();
+    let mut where_clause = where_clause.map_or_else(
+        || WhereClause { where_token: Default::default(), predicates: Default::default() },
+        Clone::clone,
+    );
+
+    let init_method = contains_initialize_with(&input.attrs);
+    let return_value = match &input.fields {
+        Fields::Named(fields) => {
+            let mut body = TokenStream::new();
+            for field in &fields.named {
+                let field_name = field.ident.as_ref().unwrap();
+
+                let delta = if contains_skip(&field.attrs) {
+                    quote! {
+                        #field_name: Default::default(),
+                    }
+                } else {
+                    let field_type = &field.ty;
+                    where_clause.predicates.push(
+                        syn::parse2(quote! {
+                            #field_type: #cratename::AsyncDecodable
+                        })
+                        .unwrap(),
+                    );
+
+                    quote! {
+                        #field_name: #cratename::AsyncDecodable::decode_async(d).await?,
+                    }
+                };
+                body.extend(delta);
+            }
+            quote! {
+                Self { #body }
+            }
+        }
+        Fields::Unnamed(fields) => {
+            let mut body = TokenStream::new();
+            for _ in 0..fields.unnamed.len() {
+                let delta = quote! {
+                    #cratename::AsyncDecodable::decode_async(d).await?,
+                };
+                body.extend(delta);
+            }
+            quote! {
+                Self( #body )
+            }
+        }
+        Fields::Unit => {
+            quote! {
+                Self {}
+            }
+        }
+    };
+
+    if let Some(method_ident) = init_method {
+        Ok(quote! {
+        #[async_trait]
+        impl #impl_generics #cratename::AsyncDecodable for #name #ty_generics #where_clause {
+            async fn decode_async<D: AsyncRead + Unpin + Send>(d: &mut D) -> ::std::io::Result<Self> {
+                let mut return_value = #return_value;
+                return_value.#method_ident();
+                Ok(return_value)
+            }
+        }
+        })
+    } else {
+        Ok(quote! {
+        #[async_trait]
+        impl #impl_generics #cratename::AsyncDecodable for #name #ty_generics #where_clause {
+            async fn decode_async<D: AsyncRead + Unpin + Send>(d: &mut D) -> ::std::io::Result<Self> {
+                Ok(#return_value)
+            }
+        }
+        })
+    }
+}

src/serial/derive-internal/src/helpers.rs

@@ -1,38 +0,0 @@
-/* This file is part of DarkFi (https://dark.fi)
- *
- * Copyright (C) 2020-2023 Dyne.org foundation
- *
- * This program is free software: you can redistribute it and/or modify
- * it under the terms of the GNU Affero General Public License as
- * published by the Free Software Foundation, either version 3 of the
- * License, or (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU Affero General Public License for more details.
- *
- * You should have received a copy of the GNU Affero General Public License
- * along with this program.  If not, see <https://www.gnu.org/licenses/>.
- */
-
-use syn::{Attribute, Path};
-
-pub fn contains_skip(attrs: &[Attribute]) -> bool {
-    attrs.iter().any(|attr| attr.path().is_ident("skip_serialize"))
-}
-
-pub fn contains_initialize_with(attrs: &[Attribute]) -> Option<Path> {
-    for attr in attrs.iter() {
-        if attr.path().is_ident("init_serialize") {
-            let mut res = None;
-            let _ = attr.parse_nested_meta(|meta| {
-                res = Some(meta.path);
-                Ok(())
-            });
-            return res
-        }
-    }
-
-    None
-}

src/serial/derive-internal/src/lib.rs

@@ -19,15 +19,17 @@
 //! Derive (de)serialization for enums and structs, see src/serial/derive
 use std::collections::HashMap;
 
-use proc_macro2::{Ident, Span, TokenStream};
+use proc_macro2::{Ident, TokenStream};
 use quote::quote;
-use syn::{
-    punctuated::Punctuated, token::Comma, Fields, FieldsNamed, FieldsUnnamed, Index, ItemEnum,
-    ItemStruct, Variant, WhereClause, WherePredicate,
-};
+use syn::{punctuated::Punctuated, token::Comma, Attribute, Path, Variant, WherePredicate};
 
-mod helpers;
-use helpers::{contains_initialize_with, contains_skip};
+mod sync_derive;
+pub use sync_derive::{enum_de, enum_ser, struct_de, struct_ser};
+
+#[cfg(feature = "async")]
+mod async_derive;
+#[cfg(feature = "async")]
+pub use async_derive::{async_enum_de, async_enum_ser, async_struct_de, async_struct_ser};
 
 struct VariantParts {
     where_predicates: Vec<WherePredicate>,
@@ -56,383 +58,21 @@ fn discriminant_map(variants: &Punctuated<Variant, Comma>) -> HashMap<Ident, Tok
     map
 }
 
-fn named_fields(
-    cratename: &Ident,
-    enum_ident: &Ident,
-    variant_ident: &Ident,
-    discriminant_value: &TokenStream,
-    fields: &FieldsNamed,
-) -> syn::Result<VariantParts> {
-    let mut where_predicates: Vec<WherePredicate> = vec![];
-    let mut variant_header = TokenStream::new();
-    let mut variant_body = TokenStream::new();
+pub fn contains_skip(attrs: &[Attribute]) -> bool {
+    attrs.iter().any(|attr| attr.path().is_ident("skip_serialize"))
+}
 
-    for field in &fields.named {
-        if !contains_skip(&field.attrs) {
-            let field_ident = field.ident.clone().unwrap();
-
-            variant_header.extend(quote! { #field_ident, });
-
-            let field_type = &field.ty;
-            where_predicates.push(
-                syn::parse2(quote! {
-                    #field_type: #cratename::Encodable
-                })
-                .unwrap(),
-            );
-
-            variant_body.extend(quote! {
-                len += #field_ident.encode(&mut s)?;
-            })
+pub fn contains_initialize_with(attrs: &[Attribute]) -> Option<Path> {
+    for attr in attrs.iter() {
+        if attr.path().is_ident("init_serialize") {
+            let mut res = None;
+            let _ = attr.parse_nested_meta(|meta| {
+                res = Some(meta.path);
+                Ok(())
+            });
+            return res
         }
     }
 
-    // `..` pattern matching works even if all fields were specified
-    variant_header = quote! { { #variant_header .. }};
-    let variant_idx_body = quote!(
-        #enum_ident::#variant_ident { .. } => #discriminant_value,
-    );
-
-    Ok(VariantParts { where_predicates, variant_header, variant_body, variant_idx_body })
-}
-
-fn unnamed_fields(
-    cratename: &Ident,
-    enum_ident: &Ident,
-    variant_ident: &Ident,
-    discriminant_value: &TokenStream,
-    fields: &FieldsUnnamed,
-) -> syn::Result<VariantParts> {
-    let mut where_predicates: Vec<WherePredicate> = vec![];
-    let mut variant_header = TokenStream::new();
-    let mut variant_body = TokenStream::new();
-
-    for (field_idx, field) in fields.unnamed.iter().enumerate() {
-        let field_idx = u32::try_from(field_idx).expect("up to 2^32 fields are supported");
-        if contains_skip(&field.attrs) {
-            let field_ident = Ident::new(format!("_id{}", field_idx).as_str(), Span::mixed_site());
-            variant_header.extend(quote! { #field_ident, });
-        } else {
-            let field_ident = Ident::new(format!("id{}", field_idx).as_str(), Span::mixed_site());
-            variant_header.extend(quote! { #field_ident, });
-
-            let field_type = &field.ty;
-            where_predicates.push(
-                syn::parse2(quote! {
-                    #field_type: #cratename::Encodable
-                })
-                .unwrap(),
-            );
-
-            variant_body.extend(quote! {
-                len += #field_ident.encode(&mut s)?;
-            })
-        }
-    }
-
-    variant_header = quote! { ( #variant_header )};
-    let variant_idx_body = quote!(
-        #enum_ident::#variant_ident(..) => #discriminant_value,
-    );
-
-    Ok(VariantParts { where_predicates, variant_header, variant_body, variant_idx_body })
-}
-
-pub fn enum_ser(input: &ItemEnum, cratename: Ident) -> syn::Result<TokenStream> {
-    let enum_ident = &input.ident;
-    let (impl_generics, ty_generics, where_clause) = input.generics.split_for_impl();
-    let mut where_clause = where_clause.map_or_else(
-        || WhereClause { where_token: Default::default(), predicates: Default::default() },
-        Clone::clone,
-    );
-    let mut all_variants_idx_body = TokenStream::new();
-    let mut fields_body = TokenStream::new();
-    let discriminants = discriminant_map(&input.variants);
-
-    for variant in input.variants.iter() {
-        let variant_ident = &variant.ident;
-        let discriminant_value = discriminants.get(variant_ident).unwrap();
-        let VariantParts { where_predicates, variant_header, variant_body, variant_idx_body } =
-            match &variant.fields {
-                Fields::Named(fields) => {
-                    named_fields(&cratename, enum_ident, variant_ident, discriminant_value, fields)?
-                }
-                Fields::Unnamed(fields) => unnamed_fields(
-                    &cratename,
-                    enum_ident,
-                    variant_ident,
-                    discriminant_value,
-                    fields,
-                )?,
-                Fields::Unit => {
-                    let variant_idx_body = quote!(
-                        #enum_ident::#variant_ident => #discriminant_value,
-                    );
-                    VariantParts {
-                        where_predicates: vec![],
-                        variant_header: TokenStream::new(),
-                        variant_body: TokenStream::new(),
-                        variant_idx_body,
-                    }
-                }
-            };
-        where_predicates.into_iter().for_each(|predicate| where_clause.predicates.push(predicate));
-        all_variants_idx_body.extend(variant_idx_body);
-        fields_body.extend(quote!(
-            #enum_ident::#variant_ident #variant_header => {
-                #variant_body
-            }
-        ))
-    }
-
-    Ok(quote! {
-        impl #impl_generics #cratename::Encodable for #enum_ident #ty_generics #where_clause {
-            fn encode<S: std::io::Write>(&self, mut s: S) -> ::core::result::Result<usize, std::io::Error> {
-                let variant_idx: u8 = match self {
-                    #all_variants_idx_body
-                };
-
-                let mut len = 0;
-                let bytes = variant_idx.to_le_bytes();
-                s.write_all(&bytes)?;
-                len += bytes.len();
-
-                match self {
-                    #fields_body
-                }
-
-                Ok(len)
-            }
-        }
-    })
-}
-
-pub fn enum_de(input: &ItemEnum, cratename: Ident) -> syn::Result<TokenStream> {
-    let name = &input.ident;
-    let (impl_generics, ty_generics, where_clause) = input.generics.split_for_impl();
-    let mut where_clause = where_clause.map_or_else(
-        || WhereClause { where_token: Default::default(), predicates: Default::default() },
-        Clone::clone,
-    );
-
-    let init_method = contains_initialize_with(&input.attrs);
-    let mut variant_arms = TokenStream::new();
-    let discriminants = discriminant_map(&input.variants);
-
-    for variant in input.variants.iter() {
-        let variant_ident = &variant.ident;
-        let discriminant = discriminants.get(variant_ident).unwrap();
-        let mut variant_header = TokenStream::new();
-        match &variant.fields {
-            Fields::Named(fields) => {
-                for field in &fields.named {
-                    let field_name = field.ident.as_ref().unwrap();
-                    if contains_skip(&field.attrs) {
-                        variant_header.extend(quote! {
-                            #field_name: Default::default(),
-                        });
-                    } else {
-                        let field_type = &field.ty;
-                        where_clause.predicates.push(
-                            syn::parse2(quote! {
-                                #field_type: #cratename::Decodable
-                            })
-                            .unwrap(),
-                        );
-
-                        variant_header.extend(quote! {
-                            #field_name: #cratename::Decodable::decode(&mut d)?,
-                        });
-                    }
-                }
-                variant_header = quote! { { #variant_header }};
-            }
-            Fields::Unnamed(fields) => {
-                for field in fields.unnamed.iter() {
-                    if contains_skip(&field.attrs) {
-                        variant_header.extend(quote! { Default::default(), });
-                    } else {
-                        let field_type = &field.ty;
-                        where_clause.predicates.push(
-                            syn::parse2(quote! {
-                                #field_type: #cratename::Decodable
-                            })
-                            .unwrap(),
-                        );
-
-                        variant_header.extend(quote! {
-                            #cratename::Decodable::decode(&mut d)?,
-                        });
-                    }
-                }
-                variant_header = quote! { ( #variant_header )};
-            }
-            Fields::Unit => {}
-        }
-        variant_arms.extend(quote! {
-            if variant_tag == #discriminant { #name::#variant_ident #variant_header } else
-        });
-    }
-
-    let init = if let Some(method_ident) = init_method {
-        quote! {
-            return_value.#method_ident();
-        }
-    } else {
-        quote! {}
-    };
-
-    Ok(quote! {
-    impl #impl_generics #cratename::Decodable for #name #ty_generics #where_clause {
-        fn decode<D: std::io::Read>(mut d: D) -> ::core::result::Result<Self, std::io::Error> {
-            let variant_tag: u8 = #cratename::Decodable::decode(&mut d)?;
-
-            let mut return_value =
-                #variant_arms {
-                    return Err(std::io::Error::new(
-                        std::io::ErrorKind::InvalidData,
-                        format!("Unexpected variant tag: {:?}", variant_tag),
-                    ))
-                };
-                #init
-                Ok(return_value)
-            }
-        }
-    })
-}
-
-pub fn struct_ser(input: &ItemStruct, cratename: Ident) -> syn::Result<TokenStream> {
-    let name = &input.ident;
-    let (impl_generics, ty_generics, where_clause) = input.generics.split_for_impl();
-    let mut where_clause = where_clause.map_or_else(
-        || WhereClause { where_token: Default::default(), predicates: Default::default() },
-        Clone::clone,
-    );
-
-    let mut body = TokenStream::new();
-
-    match &input.fields {
-        Fields::Named(fields) => {
-            for field in &fields.named {
-                if contains_skip(&field.attrs) {
-                    continue
-                }
-
-                let field_name = field.ident.as_ref().unwrap();
-                let delta = quote! {
-                    len += self.#field_name.encode(&mut s)?;
-                };
-                body.extend(delta);
-
-                let field_type = &field.ty;
-                where_clause.predicates.push(
-                    syn::parse2(quote! {
-                        #field_type: #cratename::Encodable
-                    })
-                    .unwrap(),
-                );
-            }
-        }
-        Fields::Unnamed(fields) => {
-            for field_idx in 0..fields.unnamed.len() {
-                let field_idx = Index {
-                    index: u32::try_from(field_idx).expect("up to 2^32 fields are supported"),
-                    span: Span::call_site(),
-                };
-                let delta = quote! {
-                    len += self.#field_idx.encode(&mut s)?;
-                };
-                body.extend(delta);
-            }
-        }
-        Fields::Unit => {}
-    }
-
-    Ok(quote! {
-        impl #impl_generics #cratename::Encodable for #name #ty_generics #where_clause {
-            fn encode<S: std::io::Write>(&self, mut s: S) -> ::core::result::Result<usize, std::io::Error> {
-                let mut len = 0;
-                #body
-                Ok(len)
-            }
-        }
-    })
-}
-
-pub fn struct_de(input: &ItemStruct, cratename: Ident) -> syn::Result<TokenStream> {
-    let name = &input.ident;
-    let (impl_generics, ty_generics, where_clause) = input.generics.split_for_impl();
-    let mut where_clause = where_clause.map_or_else(
-        || WhereClause { where_token: Default::default(), predicates: Default::default() },
-        Clone::clone,
-    );
-
-    let init_method = contains_initialize_with(&input.attrs);
-    let return_value = match &input.fields {
-        Fields::Named(fields) => {
-            let mut body = TokenStream::new();
-            for field in &fields.named {
-                let field_name = field.ident.as_ref().unwrap();
-
-                let delta = if contains_skip(&field.attrs) {
-                    quote! {
-                        #field_name: Default::default(),
-                    }
-                } else {
-                    let field_type = &field.ty;
-                    where_clause.predicates.push(
-                        syn::parse2(quote! {
-                            #field_type: #cratename::Decodable
-                        })
-                        .unwrap(),
-                    );
-
-                    quote! {
-                        #field_name: #cratename::Decodable::decode(&mut d)?,
-                    }
-                };
-                body.extend(delta);
-            }
-            quote! {
-                Self { #body }
-            }
-        }
-        Fields::Unnamed(fields) => {
-            let mut body = TokenStream::new();
-            for _ in 0..fields.unnamed.len() {
-                let delta = quote! {
-                    #cratename::Decodable::decode(&mut d)?,
-                };
-                body.extend(delta);
-            }
-            quote! {
-                Self( #body )
-            }
-        }
-        Fields::Unit => {
-            quote! {
-                Self {}
-            }
-        }
-    };
-
-    if let Some(method_ident) = init_method {
-        Ok(quote! {
-        impl #impl_generics #cratename::Decodable for #name #ty_generics #where_clause {
-            fn decode<D: std::io::Read>(mut d: D) -> ::core::result::Result<Self, std::io::Error> {
-                let mut return_value = #return_value;
-                return_value.#method_ident();
-                Ok(return_value)
-            }
-        }
-        })
-    } else {
-        Ok(quote! {
-            impl #impl_generics #cratename::Decodable for #name #ty_generics #where_clause {
-                fn decode<D: std::io::Read>(mut d: D) -> ::core::result::Result<Self, std::io::Error> {
-                    Ok(#return_value)
-                }
-            }
-        })
-    }
+    None
 }

src/serial/derive-internal/src/sync_derive.rs

@@ -0,0 +1,407 @@
+/* This file is part of DarkFi (https://dark.fi)
+ *
+ * Copyright (C) 2020-2023 Dyne.org foundation
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+//! Derive (de)serialization for enums and structs, see src/serial/derive
+use proc_macro2::{Ident, Span, TokenStream};
+use quote::quote;
+use syn::{
+    Fields, FieldsNamed, FieldsUnnamed, Index, ItemEnum, ItemStruct, WhereClause, WherePredicate,
+};
+
+use super::{contains_initialize_with, contains_skip, discriminant_map, VariantParts};
+
+fn named_fields(
+    cratename: &Ident,
+    enum_ident: &Ident,
+    variant_ident: &Ident,
+    discriminant_value: &TokenStream,
+    fields: &FieldsNamed,
+) -> syn::Result<VariantParts> {
+    let mut where_predicates: Vec<WherePredicate> = vec![];
+    let mut variant_header = TokenStream::new();
+    let mut variant_body = TokenStream::new();
+
+    for field in &fields.named {
+        if !contains_skip(&field.attrs) {
+            let field_ident = field.ident.clone().unwrap();
+
+            variant_header.extend(quote! { #field_ident, });
+
+            let field_type = &field.ty;
+            where_predicates.push(
+                syn::parse2(quote! {
+                    #field_type: #cratename::Encodable
+                })
+                .unwrap(),
+            );
+
+            variant_body.extend(quote! {
+                len += #field_ident.encode(&mut s)?;
+            })
+        }
+    }
+
+    // `..` pattern matching works even if all fields were specified
+    variant_header = quote! { { #variant_header .. }};
+    let variant_idx_body = quote!(
+        #enum_ident::#variant_ident { .. } => #discriminant_value,
+    );
+
+    Ok(VariantParts { where_predicates, variant_header, variant_body, variant_idx_body })
+}
+
+fn unnamed_fields(
+    cratename: &Ident,
+    enum_ident: &Ident,
+    variant_ident: &Ident,
+    discriminant_value: &TokenStream,
+    fields: &FieldsUnnamed,
+) -> syn::Result<VariantParts> {
+    let mut where_predicates: Vec<WherePredicate> = vec![];
+    let mut variant_header = TokenStream::new();
+    let mut variant_body = TokenStream::new();
+
+    for (field_idx, field) in fields.unnamed.iter().enumerate() {
+        let field_idx = u32::try_from(field_idx).expect("up to 2^32 fields are supported");
+        if contains_skip(&field.attrs) {
+            let field_ident = Ident::new(format!("_id{}", field_idx).as_str(), Span::mixed_site());
+            variant_header.extend(quote! { #field_ident, });
+        } else {
+            let field_ident = Ident::new(format!("id{}", field_idx).as_str(), Span::mixed_site());
+            variant_header.extend(quote! { #field_ident, });
+
+            let field_type = &field.ty;
+            where_predicates.push(
+                syn::parse2(quote! {
+                    #field_type: #cratename::Encodable
+                })
+                .unwrap(),
+            );
+
+            variant_body.extend(quote! {
+                len += #field_ident.encode(&mut s)?;
+            })
+        }
+    }
+
+    variant_header = quote! { ( #variant_header )};
+    let variant_idx_body = quote!(
+        #enum_ident::#variant_ident(..) => #discriminant_value,
+    );
+
+    Ok(VariantParts { where_predicates, variant_header, variant_body, variant_idx_body })
+}
+
+pub fn enum_ser(input: &ItemEnum, cratename: Ident) -> syn::Result<TokenStream> {
+    let enum_ident = &input.ident;
+    let (impl_generics, ty_generics, where_clause) = input.generics.split_for_impl();
+    let mut where_clause = where_clause.map_or_else(
+        || WhereClause { where_token: Default::default(), predicates: Default::default() },
+        Clone::clone,
+    );
+    let mut all_variants_idx_body = TokenStream::new();
+    let mut fields_body = TokenStream::new();
+    let discriminants = discriminant_map(&input.variants);
+
+    for variant in input.variants.iter() {
+        let variant_ident = &variant.ident;
+        let discriminant_value = discriminants.get(variant_ident).unwrap();
+        let VariantParts { where_predicates, variant_header, variant_body, variant_idx_body } =
+            match &variant.fields {
+                Fields::Named(fields) => {
+                    named_fields(&cratename, enum_ident, variant_ident, discriminant_value, fields)?
+                }
+                Fields::Unnamed(fields) => unnamed_fields(
+                    &cratename,
+                    enum_ident,
+                    variant_ident,
+                    discriminant_value,
+                    fields,
+                )?,
+                Fields::Unit => {
+                    let variant_idx_body = quote!(
+                        #enum_ident::#variant_ident => #discriminant_value,
+                    );
+                    VariantParts {
+                        where_predicates: vec![],
+                        variant_header: TokenStream::new(),
+                        variant_body: TokenStream::new(),
+                        variant_idx_body,
+                    }
+                }
+            };
+        where_predicates.into_iter().for_each(|predicate| where_clause.predicates.push(predicate));
+        all_variants_idx_body.extend(variant_idx_body);
+        fields_body.extend(quote!(
+            #enum_ident::#variant_ident #variant_header => {
+                #variant_body
+            }
+        ))
+    }
+
+    Ok(quote! {
+        impl #impl_generics #cratename::Encodable for #enum_ident #ty_generics #where_clause {
+            fn encode<S: std::io::Write>(&self, mut s: S) -> ::core::result::Result<usize, std::io::Error> {
+                let variant_idx: u8 = match self {
+                    #all_variants_idx_body
+                };
+
+                let mut len = 0;
+                let bytes = variant_idx.to_le_bytes();
+                s.write_all(&bytes)?;
+                len += bytes.len();
+
+                match self {
+                    #fields_body
+                }
+
+                Ok(len)
+            }
+        }
+    })
+}
+
+pub fn enum_de(input: &ItemEnum, cratename: Ident) -> syn::Result<TokenStream> {
+    let name = &input.ident;
+    let (impl_generics, ty_generics, where_clause) = input.generics.split_for_impl();
+    let mut where_clause = where_clause.map_or_else(
+        || WhereClause { where_token: Default::default(), predicates: Default::default() },
+        Clone::clone,
+    );
+
+    let init_method = contains_initialize_with(&input.attrs);
+    let mut variant_arms = TokenStream::new();
+    let discriminants = discriminant_map(&input.variants);
+
+    for variant in input.variants.iter() {
+        let variant_ident = &variant.ident;
+        let discriminant = discriminants.get(variant_ident).unwrap();
+        let mut variant_header = TokenStream::new();
+        match &variant.fields {
+            Fields::Named(fields) => {
+                for field in &fields.named {
+                    let field_name = field.ident.as_ref().unwrap();
+                    if contains_skip(&field.attrs) {
+                        variant_header.extend(quote! {
+                            #field_name: Default::default(),
+                        });
+                    } else {
+                        let field_type = &field.ty;
+                        where_clause.predicates.push(
+                            syn::parse2(quote! {
+                                #field_type: #cratename::Decodable
+                            })
+                            .unwrap(),
+                        );
+
+                        variant_header.extend(quote! {
+                            #field_name: #cratename::Decodable::decode(&mut d)?,
+                        });
+                    }
+                }
+                variant_header = quote! { { #variant_header }};
+            }
+            Fields::Unnamed(fields) => {
+                for field in fields.unnamed.iter() {
+                    if contains_skip(&field.attrs) {
+                        variant_header.extend(quote! { Default::default(), });
+                    } else {
+                        let field_type = &field.ty;
+                        where_clause.predicates.push(
+                            syn::parse2(quote! {
+                                #field_type: #cratename::Decodable
+                            })
+                            .unwrap(),
+                        );
+
+                        variant_header.extend(quote! {
+                            #cratename::Decodable::decode(&mut d)?,
+                        });
+                    }
+                }
+                variant_header = quote! { ( #variant_header )};
+            }
+            Fields::Unit => {}
+        }
+        variant_arms.extend(quote! {
+            if variant_tag == #discriminant { #name::#variant_ident #variant_header } else
+        });
+    }
+
+    let init = if let Some(method_ident) = init_method {
+        quote! {
+            return_value.#method_ident();
+        }
+    } else {
+        quote! {}
+    };
+
+    Ok(quote! {
+    impl #impl_generics #cratename::Decodable for #name #ty_generics #where_clause {
+        fn decode<D: std::io::Read>(mut d: D) -> ::core::result::Result<Self, std::io::Error> {
+            let variant_tag: u8 = #cratename::Decodable::decode(&mut d)?;
+
+            let mut return_value =
+                #variant_arms {
+                    return Err(std::io::Error::new(
+                        std::io::ErrorKind::InvalidData,
+                        format!("Unexpected variant tag: {:?}", variant_tag),
+                    ))
+                };
+                #init
+                Ok(return_value)
+            }
+        }
+    })
+}
+
+pub fn struct_ser(input: &ItemStruct, cratename: Ident) -> syn::Result<TokenStream> {
+    let name = &input.ident;
+    let (impl_generics, ty_generics, where_clause) = input.generics.split_for_impl();
+    let mut where_clause = where_clause.map_or_else(
+        || WhereClause { where_token: Default::default(), predicates: Default::default() },
+        Clone::clone,
+    );
+
+    let mut body = TokenStream::new();
+
+    match &input.fields {
+        Fields::Named(fields) => {
+            for field in &fields.named {
+                if contains_skip(&field.attrs) {
+                    continue
+                }
+
+                let field_name = field.ident.as_ref().unwrap();
+                let delta = quote! {
+                    len += self.#field_name.encode(&mut s)?;
+                };
+                body.extend(delta);
+
+                let field_type = &field.ty;
+                where_clause.predicates.push(
+                    syn::parse2(quote! {
+                        #field_type: #cratename::Encodable
+                    })
+                    .unwrap(),
+                );
+            }
+        }
+        Fields::Unnamed(fields) => {
+            for field_idx in 0..fields.unnamed.len() {
+                let field_idx = Index {
+                    index: u32::try_from(field_idx).expect("up to 2^32 fields are supported"),
+                    span: Span::call_site(),
+                };
+                let delta = quote! {
+                    len += self.#field_idx.encode(&mut s)?;
+                };
+                body.extend(delta);
+            }
+        }
+        Fields::Unit => {}
+    }
+
+    Ok(quote! {
+        impl #impl_generics #cratename::Encodable for #name #ty_generics #where_clause {
+            fn encode<S: std::io::Write>(&self, mut s: S) -> ::core::result::Result<usize, std::io::Error> {
+                let mut len = 0;
+                #body
+                Ok(len)
+            }
+        }
+    })
+}
+
+pub fn struct_de(input: &ItemStruct, cratename: Ident) -> syn::Result<TokenStream> {
+    let name = &input.ident;
+    let (impl_generics, ty_generics, where_clause) = input.generics.split_for_impl();
+    let mut where_clause = where_clause.map_or_else(
+        || WhereClause { where_token: Default::default(), predicates: Default::default() },
+        Clone::clone,
+    );
+
+    let init_method = contains_initialize_with(&input.attrs);
+    let return_value = match &input.fields {
+        Fields::Named(fields) => {
+            let mut body = TokenStream::new();
+            for field in &fields.named {
+                let field_name = field.ident.as_ref().unwrap();
+
+                let delta = if contains_skip(&field.attrs) {
+                    quote! {
+                        #field_name: Default::default(),
+                    }
+                } else {
+                    let field_type = &field.ty;
+                    where_clause.predicates.push(
+                        syn::parse2(quote! {
+                            #field_type: #cratename::Decodable
+                        })
+                        .unwrap(),
+                    );
+
+                    quote! {
+                        #field_name: #cratename::Decodable::decode(&mut d)?,
+                    }
+                };
+                body.extend(delta);
+            }
+            quote! {
+                Self { #body }
+            }
+        }
+        Fields::Unnamed(fields) => {
+            let mut body = TokenStream::new();
+            for _ in 0..fields.unnamed.len() {
+                let delta = quote! {
+                    #cratename::Decodable::decode(&mut d)?,
+                };
+                body.extend(delta);
+            }
+            quote! {
+                Self( #body )
+            }
+        }
+        Fields::Unit => {
+            quote! {
+                Self {}
+            }
+        }
+    };
+
+    if let Some(method_ident) = init_method {
+        Ok(quote! {
+        impl #impl_generics #cratename::Decodable for #name #ty_generics #where_clause {
+            fn decode<D: std::io::Read>(mut d: D) -> ::core::result::Result<Self, std::io::Error> {
+                let mut return_value = #return_value;
+                return_value.#method_ident();
+                Ok(return_value)
+            }
+        }
+        })
+    } else {
+        Ok(quote! {
+            impl #impl_generics #cratename::Decodable for #name #ty_generics #where_clause {
+                fn decode<D: std::io::Read>(mut d: D) -> ::core::result::Result<Self, std::io::Error> {
+                    Ok(#return_value)
+                }
+            }
+        })
+    }
+}