Outgoing derive: Replace incoming_no_deserialize with incoming_derive(!Deserialize)

ruma-api-macros/src/api/request.rs

@@ -494,7 +494,7 @@ impl ToTokens for Request {
 
         let request = quote! {
             #[derive(Debug, Clone, #import_path::Outgoing)]
-            #[incoming_no_deserialize]
+            #[incoming_derive(!Deserialize)]
             #( #struct_attributes )*
             pub struct Request #request_generics #request_def
 

ruma-api-macros/src/api/response.rs

@@ -283,7 +283,7 @@ impl ToTokens for Response {
 
         let response = quote! {
             #[derive(Debug, Clone, #import_path::Outgoing)]
-            #[incoming_no_deserialize]
+            #[incoming_derive(!Deserialize)]
             #( #struct_attributes )*
             pub struct Response #response_def
 

ruma-api-macros/src/derive_outgoing.rs

@@ -1,10 +1,12 @@
 use proc_macro2::{Span, TokenStream};
 use quote::{format_ident, quote};
 use syn::{
-    parse_quote, AngleBracketedGenericArguments, Attribute, Data, DeriveInput, Field, Fields,
-    GenericArgument, GenericParam, Generics, ImplGenerics, Meta, MetaList,
-    ParenthesizedGenericArguments, PathArguments, Type, TypeGenerics, TypePath, TypeReference,
-    TypeSlice, Variant,
+    parse::{Parse, ParseStream},
+    parse_quote,
+    punctuated::Punctuated,
+    AngleBracketedGenericArguments, Attribute, Data, DeriveInput, Field, Fields, GenericArgument,
+    GenericParam, Generics, Ident, ImplGenerics, ParenthesizedGenericArguments, PathArguments,
+    Token, Type, TypeGenerics, TypePath, TypeReference, TypeSlice, Variant,
 };
 
 use crate::util::import_ruma_api;
@@ -24,29 +26,28 @@ pub fn expand_derive_outgoing(input: DeriveInput) -> syn::Result<TokenStream> {
     let import_path = import_ruma_api();
 
     let mut derives = vec![quote! { Debug }];
-    if !no_deserialize_in_attrs(&input.attrs) {
-        derives.push(quote! { #import_path::exports::serde::Deserialize });
-    }
+    let mut derive_deserialize = true;
+
     derives.extend(
         input
             .attrs
             .iter()
             .filter(|attr| attr.path.is_ident("incoming_derive"))
-            .map(|attr| {
-                let meta = attr.parse_meta()?;
-                match meta {
-                    Meta::List(MetaList { nested, .. }) => Ok(nested),
-                    _ => Err(syn::Error::new_spanned(
-                        meta,
-                        "incoming_derive should be used as `#[incoming_derive(A, B, C)]`",
-                    )),
-                }
-            })
-            .collect::<syn::Result<Vec<_>>>()?
+            .map(|attr| attr.parse_args())
+            .collect::<syn::Result<Vec<Meta>>>()?
             .into_iter()
-            .flatten()
-            .map(|derive_mac| quote! { #derive_mac }),
+            .flat_map(|meta| meta.derive_macs)
+            .filter_map(|derive_mac| match derive_mac {
+                DeriveMac::Regular(id) => Some(quote! { #id }),
+                DeriveMac::NegativeDeserialize => {
+                    derive_deserialize = false;
+                    None
+                }
+            }),
     );
+    if derive_deserialize {
+        derives.push(quote! { #import_path::exports::serde::Deserialize });
+    }
 
     let input_attrs =
         input.attrs.iter().filter(|attr| filter_input_attrs(attr)).collect::<Vec<_>>();
@@ -149,10 +150,6 @@ fn filter_input_attrs(attr: &Attribute) -> bool {
     attr.path.is_ident("serde") || attr.path.is_ident("non_exhaustive")
 }
 
-fn no_deserialize_in_attrs(attrs: &[Attribute]) -> bool {
-    attrs.iter().any(|attr| attr.path.is_ident("incoming_no_deserialize"))
-}
-
 fn impl_outgoing_with_incoming_self(input: &DeriveInput, import_path: &TokenStream) -> TokenStream {
     let ident = &input.ident;
     let (impl_gen, ty_gen, _) = input.generics.split_for_impl();
@@ -283,3 +280,41 @@ fn strip_lifetimes(field_type: &mut Type) -> bool {
         _ => false,
     }
 }
+
+pub struct Meta {
+    derive_macs: Vec<DeriveMac>,
+}
+
+impl Parse for Meta {
+    fn parse(input: ParseStream) -> syn::Result<Self> {
+        Ok(Self {
+            derive_macs: Punctuated::<_, Token![,]>::parse_terminated(input)?.into_iter().collect(),
+        })
+    }
+}
+
+pub enum DeriveMac {
+    Regular(Ident),
+    NegativeDeserialize,
+}
+
+impl Parse for DeriveMac {
+    fn parse(input: ParseStream) -> syn::Result<Self> {
+        if input.peek(Token![!]) {
+            let _: Token![!] = input.parse()?;
+            let mac: Ident = input.parse()?;
+
+            if mac != "Deserialize" {
+                return Err(syn::Error::new_spanned(
+                    mac,
+                    "Negative incoming_derive can only be used for Deserialize",
+                ));
+            }
+
+            Ok(Self::NegativeDeserialize)
+        } else {
+            let mac = input.parse()?;
+            Ok(Self::Regular(mac))
+        }
+    }
+}

ruma-api-macros/src/lib.rs

@@ -76,7 +76,7 @@ struct IncomingMyType {
 ```
 
 */
-#[proc_macro_derive(Outgoing, attributes(incoming_derive, incoming_no_deserialize))]
+#[proc_macro_derive(Outgoing, attributes(incoming_derive))]
 pub fn derive_outgoing(input: TokenStream) -> TokenStream {
     let input = parse_macro_input!(input as DeriveInput);
     expand_derive_outgoing(input).unwrap_or_else(|err| err.to_compile_error()).into()

ruma-api/tests/outgoing.rs

@@ -21,7 +21,7 @@ pub struct OtherThing<'t> {
 }
 
 #[derive(Outgoing)]
-#[incoming_no_deserialize]
+#[incoming_derive(!Deserialize)]
 pub struct FakeRequest<'a, T> {
     pub abc: &'a str,
     pub thing: Thing<'a, T>,
@@ -35,7 +35,7 @@ pub struct FakeRequest<'a, T> {
 }
 
 #[derive(Outgoing)]
-#[incoming_no_deserialize]
+#[incoming_derive(!Deserialize)]
 pub enum EnumThing<'a, T> {
     Abc(&'a str),
     Stuff(Thing<'a, T>),

ruma-client-api/src/r0/message/send_message_event.rs

@@ -19,7 +19,7 @@ use serde_json::value::RawValue as RawJsonValue;
 /// Send a message event to a room.
 #[derive(Clone, Debug, Outgoing)]
 #[non_exhaustive]
-#[incoming_no_deserialize]
+#[incoming_derive(!Deserialize)]
 pub struct Request<'a> {
     /// The room to send the event to.
     pub room_id: &'a RoomId,
@@ -45,7 +45,7 @@ impl<'a> Request<'a> {
 /// Data in the response from the `send_message_event` API endpoint.
 #[derive(Clone, Debug, Outgoing)]
 #[non_exhaustive]
-#[incoming_no_deserialize]
+#[incoming_derive(!Deserialize)]
 pub struct Response {
     /// A unique identifier for the event.
     pub event_id: EventId,

ruma-client-api/src/r0/state/send_state_event_for_empty_key.rs

@@ -19,7 +19,7 @@ use serde_json::value::RawValue as RawJsonValue;
 /// Send a state event to a room associated with the empty state key.
 #[derive(Clone, Debug, Outgoing)]
 #[non_exhaustive]
-#[incoming_no_deserialize]
+#[incoming_derive(!Deserialize)]
 pub struct Request<'a> {
     /// The room to set the state in.
     pub room_id: &'a RoomId,
@@ -38,7 +38,7 @@ impl<'a> Request<'a> {
 /// Data in the response from the `send_state_event_for_empty_key` API endpoint.
 #[derive(Clone, Debug, Outgoing)]
 #[non_exhaustive]
-#[incoming_no_deserialize]
+#[incoming_derive(!Deserialize)]
 pub struct Response {
     /// A unique identifier for the event.
     pub event_id: EventId,

ruma-client-api/src/r0/state/send_state_event_for_key.rs

@@ -19,7 +19,7 @@ use serde_json::value::RawValue as RawJsonValue;
 /// Send a state event to a room associated with a given state key.
 #[derive(Clone, Debug, Outgoing)]
 #[non_exhaustive]
-#[incoming_no_deserialize]
+#[incoming_derive(!Deserialize)]
 pub struct Request<'a> {
     /// The room to set the state in.
     pub room_id: &'a RoomId,
@@ -41,7 +41,7 @@ impl<'a> Request<'a> {
 /// Data in the response from the `send_message_event` API endpoint.
 #[derive(Clone, Debug, Outgoing)]
 #[non_exhaustive]
-#[incoming_no_deserialize]
+#[incoming_derive(!Deserialize)]
 pub struct Response {
     /// A unique identifier for the event.
     pub event_id: EventId,