allow trailling comma in decl_event (#2117)

* allow trailling comma in decl_event

* Update srml/support/src/event.rs

Co-Authored-By: xlc <xlchen1291@gmail.com>

* Update srml/support/src/event.rs

Co-Authored-By: xlc <xlchen1291@gmail.com>

* Update srml/support/src/event.rs

Co-Authored-By: xlc <xlchen1291@gmail.com>

* Update srml/support/src/event.rs

Co-Authored-By: xlc <xlchen1291@gmail.com>

* Update srml/support/src/event.rs

Co-Authored-By: xlc <xlchen1291@gmail.com>

* bump version and update wasm

substrate/node/runtime/src/lib.rs

@@ -59,7 +59,7 @@ pub const VERSION: RuntimeVersion = RuntimeVersion {
 	impl_name: create_runtime_str!("substrate-node"),
 	authoring_version: 10,
 	spec_version: 48,
-	impl_version: 48,
+	impl_version: 49,
 	apis: RUNTIME_API_VERSIONS,
 };
 

substrate/srml/support/src/event.rs

@@ -183,79 +183,79 @@ macro_rules! __decl_generic_event {
 			{};
 		);
 	};
-	// Parse named
+	// Finish formatting on an unnamed one
 	(@format_generic
 		$(#[$attr:meta])*;
 		$event_generic_param:ident;
 		$($instance:ident $( = $event_default_instance:path)? )?;
-		{ $generic_rename:ident = $generic_type:ty, $($rest:tt)* };
+		{ <$generic:ident as $trait:path>::$trait_type:ident $(,)? { $( $events:tt )* } };
 		{$( $parsed:tt)*};
 	) => {
-		$crate::__decl_generic_event!(@format_generic
+		$crate::__decl_generic_event!(@generate
 			$( #[ $attr ] )*;
 			$event_generic_param;
 			$($instance $( = $event_default_instance)? )?;
-			{ $($rest)* };
-			{ $($parsed)*, $generic_rename = $generic_type };
+			{ $($events)* };
+			{ $($parsed)*, $trait_type = <$generic as $trait>::$trait_type };
 		);
 	};
-	// Parse unnamed
+	// Finish formatting on a named one
 	(@format_generic
 		$(#[$attr:meta])*;
 		$event_generic_param:ident;
 		$($instance:ident $( = $event_default_instance:path)? )?;
-		{ <$generic:ident as $trait:path>::$trait_type:ident, $($rest:tt)* };
-		{$($parsed:tt)*};
+		{ $generic_rename:ident = $generic_type:ty $(,)? { $( $events:tt )* } };
+		{ $($parsed:tt)* };
 	) => {
-		$crate::__decl_generic_event!(@format_generic
-			$( #[ $attr ] )*;
+		$crate::__decl_generic_event!(@generate
+			$(#[$attr])*;
 			$event_generic_param;
 			$($instance $( = $event_default_instance)? )?;
-			{ $($rest)* };
-			{ $($parsed)*, $trait_type = <$generic as $trait>::$trait_type };
+			{ $($events)* };
+			{ $($parsed)*, $generic_rename = $generic_type };
 		);
 	};
-	// Unnamed type can't be parsed
+	// Parse named
 	(@format_generic
 		$(#[$attr:meta])*;
 		$event_generic_param:ident;
 		$($instance:ident $( = $event_default_instance:path)? )?;
-		{ $generic_type:ty, $($rest:tt)* };
-		{$($parsed:tt)*};
+		{ $generic_rename:ident = $generic_type:ty, $($rest:tt)* };
+		{$( $parsed:tt)*};
 	) => {
-		$crate::__decl_generic_event!(@cannot_parse $generic_type);
+		$crate::__decl_generic_event!(@format_generic
+			$( #[ $attr ] )*;
+			$event_generic_param;
+			$( $instance $( = $event_default_instance)? )?;
+			{ $($rest)* };
+			{ $($parsed)*, $generic_rename = $generic_type };
+		);
 	};
-	// Finish formatting on an unnamed one
+	// Parse unnamed
 	(@format_generic
 		$(#[$attr:meta])*;
 		$event_generic_param:ident;
 		$($instance:ident $( = $event_default_instance:path)? )?;
-		{ <$generic:ident as $trait:path>::$trait_type:ident { $( $events:tt )* } };
-		{$( $parsed:tt)*};
+		{ <$generic:ident as $trait:path>::$trait_type:ident, $($rest:tt)* };
+		{$($parsed:tt)*};
 	) => {
-		$crate::__decl_generic_event!(@generate
+		$crate::__decl_generic_event!(@format_generic
 			$( #[ $attr ] )*;
 			$event_generic_param;
 			$($instance $( = $event_default_instance)? )?;
-			{ $($events)* };
-			{ $($parsed)*, $trait_type = <$generic as $trait>::$trait_type};
+			{ $($rest)* };
+			{ $($parsed)*, $trait_type = <$generic as $trait>::$trait_type };
 		);
 	};
-	// Finish formatting on a named one
+	// Unnamed type can't be parsed
 	(@format_generic
 		$(#[$attr:meta])*;
 		$event_generic_param:ident;
 		$($instance:ident $( = $event_default_instance:path)? )?;
-		{ $generic_rename:ident = $generic_type:ty { $( $events:tt )* } };
-		{$( $parsed:tt)*};
+		{ $generic_type:ty, $($rest:tt)* };
+		{ $($parsed:tt)* };
 	) => {
-		$crate::__decl_generic_event!(@generate
-			$(#[$attr])*;
-			$event_generic_param;
-			$($instance $( = $event_default_instance)? )?;
-			{ $($events)* };
-			{ $($parsed)*, $generic_rename = $generic_type};
-		);
+		$crate::__decl_generic_event!(@cannot_parse $generic_type);
 	};
 	// Final unnamed type can't be parsed
 	(@format_generic
@@ -599,6 +599,50 @@ mod tests {
 		);
 	}
 
+	mod event_module4 {
+		pub trait Trait {
+			type Origin;
+			type Balance;
+			type BlockNumber;
+		}
+
+		decl_module! {
+			pub struct Module<T: Trait> for enum Call where origin: T::Origin {}
+		}
+
+		decl_event!(
+			/// Event finish formatting on an unnamed one with trailling comma
+			pub enum Event<T> where
+				<T as Trait>::Balance,
+				<T as Trait>::Origin,
+			{
+				TestEvent(Balance, Origin),
+			}
+		);
+	}
+
+	mod event_module5 {
+		pub trait Trait {
+			type Origin;
+			type Balance;
+			type BlockNumber;
+		}
+
+		decl_module! {
+			pub struct Module<T: Trait> for enum Call where origin: T::Origin {}
+		}
+
+		decl_event!(
+			/// Event finish formatting on an named one with trailling comma
+			pub enum Event<T> where
+				BalanceRenamed = <T as Trait>::Balance,
+				OriginRenamed = <T as Trait>::Origin,
+			{
+				TestEvent(BalanceRenamed, OriginRenamed),
+			}
+		);
+	}
+
 	#[derive(Debug, Clone, PartialEq, Eq, Encode, Decode, Serialize)]
 	pub struct TestRuntime;