From 98398b4b458253298c96812945f80649378c652a Mon Sep 17 00:00:00 2001
From: Michal Kucharczyk <1728078+michalkucharczyk@users.noreply.github.com>
Date: Wed, 17 May 2023 08:57:09 +0200
Subject: [PATCH] frame::support: macro generating GenesisBuild::build for
 RuntimeGenesisConfig

---
 .../src/construct_runtime/expand/config.rs    | 31 +++++++++++++++++++
 1 file changed, 31 insertions(+)

diff --git a/frame/support/procedural/src/construct_runtime/expand/config.rs b/frame/support/procedural/src/construct_runtime/expand/config.rs
index f74e8cbf4d088..02cb6fd065ead 100644
--- a/frame/support/procedural/src/construct_runtime/expand/config.rs
+++ b/frame/support/procedural/src/construct_runtime/expand/config.rs
@@ -30,6 +30,7 @@ pub fn expand_outer_config(
 	let mut types = TokenStream::new();
 	let mut fields = TokenStream::new();
 	let mut build_storage_calls = TokenStream::new();
+	let mut genesis_build_calls = TokenStream::new();
 	let mut query_genesis_config_part_macros = Vec::new();
 
 	for decl in pallet_decls {
@@ -54,6 +55,9 @@ pub fn expand_outer_config(
 			fields.extend(quote!(#attr pub #field_name: #config,));
 			build_storage_calls
 				.extend(expand_config_build_storage_call(scrate, attr, runtime, decl, field_name));
+			genesis_build_calls.extend(expand_config_genesis_build_call(
+				scrate, &config, attr, runtime, decl, field_name,
+			));
 			query_genesis_config_part_macros.push(quote! {
 				#path::__substrate_genesis_config_check::is_genesis_config_defined!(#pallet_name);
 				#[cfg(feature = "std")]
@@ -95,6 +99,12 @@ pub fn expand_outer_config(
 				Ok(())
 			}
 		}
+
+		impl<T> #scrate::traits::GenesisBuild<T> for RuntimeGenesisConfig {
+			fn build(&self) {
+				#genesis_build_calls
+			}
+		}
 	}
 }
 
@@ -143,3 +153,24 @@ fn expand_config_build_storage_call(
 			<#runtime, #instance>::build_module_genesis_storage(&self.#field_name, storage)?;
 	}
 }
+
+fn expand_config_genesis_build_call(
+	scrate: &TokenStream,
+	pallet_genesis_config: &Ident,
+	attr: &TokenStream,
+	runtime: &Ident,
+	decl: &Pallet,
+	field_name: &Ident,
+) -> TokenStream {
+	let path = &decl.path;
+	let instance = if let Some(inst) = decl.instance.as_ref() {
+		quote!(#path::#inst)
+	} else {
+		quote!(#path::__InherentHiddenInstance)
+	};
+
+	quote! {
+		#attr
+		<#pallet_genesis_config as #scrate::traits::GenesisBuild::<#runtime, #instance>>::build(&self.#field_name);
+	}
+}