Record pallet indices in CallMetadata

frame/support/procedural/src/construct_runtime/expand/call.rs

@@ -29,6 +29,7 @@ pub fn expand_outer_dispatch(
 	let mut variant_patterns = Vec::new();
 	let mut query_call_part_macros = Vec::new();
 	let mut pallet_names = Vec::new();
+	let mut pallet_indices = Vec::new();
 
 	let pallets_with_call = pallet_decls.iter().filter(|decl| decl.exists_part("Call"));
 
@@ -42,6 +43,7 @@ pub fn expand_outer_dispatch(
 		);
 		variant_patterns.push(quote!(Call::#name(call)));
 		pallet_names.push(name);
+		pallet_indices.push(index);
 		query_call_part_macros.push(quote! {
 			#path::__substrate_call_check::is_call_part_defined!(#name);
 		});
@@ -74,7 +76,8 @@ pub fn expand_outer_dispatch(
 						#variant_patterns => {
 							let function_name = call.get_call_name();
 							let pallet_name = stringify!(#pallet_names);
-							#scrate::dispatch::CallMetadata { function_name, pallet_name }
+							let index = #pallet_indices;
+							#scrate::dispatch::CallMetadata { function_name, pallet_name, index }
 						}
 					)*
 				}

frame/support/src/traits/metadata.rs

@@ -48,6 +48,8 @@ pub struct CallMetadata {
 	pub function_name: &'static str,
 	/// Name of the pallet to which the function belongs.
 	pub pallet_name: &'static str,
+	/// Index of the pallet specified in `construct_runtime`.
+	pub index: u8,
 }
 
 /// Gets the function name of the Call.