sp-api: Set correct where bound in the generated code

primitives/api/proc-macro/src/runtime_metadata.rs

@@ -162,15 +162,18 @@ pub fn generate_decl_runtime_metadata(decl: &ItemTrait) -> TokenStream2 {
  ty.default = None;
  }
 
- let where_clause = where_clause
- .iter()
- .map(|ty| quote!(#ty: #crate_::scale_info::TypeInfo + 'static));
+ where_clause
+ .into_iter()
+ .map(|ty| parse_quote!(#ty: #crate_::scale_info::TypeInfo + 'static))
+ .for_each(|w| generics.make_where_clause().predicates.push(w));
+
+ let (impl_generics, _, where_clause) = generics.split_for_impl();
 
  quote!(
  #( #attrs )*
  #[inline(always)]
- pub fn runtime_metadata #generics () -> #crate_::metadata_ir::RuntimeApiMetadataIR
- where #( #where_clause, )*
+ pub fn runtime_metadata #impl_generics () -> #crate_::metadata_ir::RuntimeApiMetadataIR
+ #where_clause
  {
  #crate_::metadata_ir::RuntimeApiMetadataIR {
  name: #trait_name,

primitives/api/test/Cargo.toml

@@ -23,6 +23,7 @@ codec = { package = "parity-scale-codec", version = "3.2.2" }
 sp-state-machine = { version = "0.13.0", path = "../../state-machine" }
 trybuild = "1.0.74"
 rustversion = "1.0.6"
+scale-info = { version = "2.5.0", default-features = false, features = ["derive"] }
 
 [dev-dependencies]
 criterion = "0.4.0"

primitives/api/test/tests/ui/positive_cases/custom_where_bound.rs

@@ -0,0 +1,46 @@
+use codec::{Decode, Encode};
+use scale_info::TypeInfo;
+use sp_runtime::traits::{Block as BlockT, GetNodeBlockType};
+use substrate_test_runtime_client::runtime::Block;
+
+struct Runtime {}
+impl GetNodeBlockType for Runtime {
+ type NodeBlock = Block;
+}
+
+pub trait CustomTrait: Encode + Decode + TypeInfo {}
+
+#[derive(Encode, Decode, TypeInfo)]
+pub struct SomeImpl;
+impl CustomTrait for SomeImpl {}
+
+#[derive(Encode, Decode, TypeInfo)]
+pub struct SomeOtherType<C: CustomTrait>(C);
+
+sp_api::decl_runtime_apis! {
+ pub trait Api<A> where A: CustomTrait {
+ fn test() -> A;
+ fn test2() -> SomeOtherType<A>;
+ }
+}
+
+sp_api::impl_runtime_apis! {
+ impl self::Api<Block, SomeImpl> for Runtime {
+ fn test() -> SomeImpl { SomeImpl }
+ fn test2() -> SomeOtherType<SomeImpl> { SomeOtherType(SomeImpl) }
+ }
+
+ impl sp_api::Core<Block> for Runtime {
+ fn version() -> sp_version::RuntimeVersion {
+ unimplemented!()
+ }
+ fn execute_block(_: Block) {
+ unimplemented!()
+ }
+ fn initialize_block(_: &<Block as BlockT>::Header) {
+ unimplemented!()
+ }
+ }
+}
+
+fn main() {}