From 479c84cacee0009eb5632754295c039bf96f706d Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Bastian=20K=C3=B6cher?= <bkchr@users.noreply.github.com>
Date: Fri, 29 Jul 2022 10:22:49 +0100
Subject: [PATCH] construct_runtime!: Support parsing `struct Runtime` (#11932)

* construct_runtime!: Support parsing `struct Runtime`

* FMT
---
 bin/node-template/runtime/src/lib.rs                    | 5 +++--
 frame/balances/src/tests_local.rs                       | 2 +-
 frame/support/procedural/src/construct_runtime/parse.rs | 9 ++++++++-
 3 files changed, 12 insertions(+), 4 deletions(-)

diff --git a/bin/node-template/runtime/src/lib.rs b/bin/node-template/runtime/src/lib.rs
index a2f595f571a90..a4382cc9038ce 100644
--- a/bin/node-template/runtime/src/lib.rs
+++ b/bin/node-template/runtime/src/lib.rs
@@ -272,10 +272,11 @@ impl pallet_template::Config for Runtime {
 
 // Create the runtime by composing the FRAME pallets that were previously configured.
 construct_runtime!(
-	pub enum Runtime where
+	pub struct Runtime
+	where
 		Block = Block,
 		NodeBlock = opaque::Block,
-		UncheckedExtrinsic = UncheckedExtrinsic
+		UncheckedExtrinsic = UncheckedExtrinsic,
 	{
 		System: frame_system,
 		RandomnessCollectiveFlip: pallet_randomness_collective_flip,
diff --git a/frame/balances/src/tests_local.rs b/frame/balances/src/tests_local.rs
index 6f4c50d90153a..48c6574c3b39f 100644
--- a/frame/balances/src/tests_local.rs
+++ b/frame/balances/src/tests_local.rs
@@ -34,7 +34,7 @@ type UncheckedExtrinsic = frame_system::mocking::MockUncheckedExtrinsic<Test>;
 type Block = frame_system::mocking::MockBlock<Test>;
 
 frame_support::construct_runtime!(
-	pub enum Test where
+	pub struct Test where
 		Block = Block,
 		NodeBlock = Block,
 		UncheckedExtrinsic = UncheckedExtrinsic,
diff --git a/frame/support/procedural/src/construct_runtime/parse.rs b/frame/support/procedural/src/construct_runtime/parse.rs
index a2cda6a0777b8..711da85c10cfc 100644
--- a/frame/support/procedural/src/construct_runtime/parse.rs
+++ b/frame/support/procedural/src/construct_runtime/parse.rs
@@ -73,7 +73,14 @@ pub struct ExplicitRuntimeDeclaration {
 impl Parse for RuntimeDeclaration {
 	fn parse(input: ParseStream) -> Result<Self> {
 		input.parse::<Token![pub]>()?;
-		input.parse::<Token![enum]>()?;
+
+		// Support either `enum` or `struct`.
+		if input.peek(Token![struct]) {
+			input.parse::<Token![struct]>()?;
+		} else {
+			input.parse::<Token![enum]>()?;
+		}
+
 		let name = input.parse::<syn::Ident>()?;
 		let where_section = input.parse()?;
 		let pallets =