Improve spans of pallet macro (paritytech#7830)

* fix spans

* convert name to snake case

frame/support/procedural/Cargo.toml

@@ -18,6 +18,7 @@ proc-macro = true
 frame-support-procedural-tools = { version = "2.0.0", path = "./tools" }
 proc-macro2 = "1.0.6"
 quote = "1.0.3"
+Inflector = "0.11.4"
 syn = { version = "1.0.7", features = ["full"] }
 
 [features]

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

@@ -24,9 +24,9 @@ use syn::spanned::Spanned;
 pub fn expand_call(def: &mut Def) -> proc_macro2::TokenStream {
 	let frame_support = &def.frame_support;
 	let frame_system = &def.frame_system;
-	let type_impl_gen = &def.type_impl_generics();
-	let type_decl_bounded_gen = &def.type_decl_bounded_generics();
-	let type_use_gen = &def.type_use_generics();
+	let type_impl_gen = &def.type_impl_generics(def.call.attr_span);
+	let type_decl_bounded_gen = &def.type_decl_bounded_generics(def.call.attr_span);
+	let type_use_gen = &def.type_use_generics(def.call.attr_span);
 	let call_ident = syn::Ident::new("Call", def.call.attr_span.clone());
 	let pallet_ident = &def.pallet_struct.pallet;
 	let where_clause = &def.call.where_clause;
@@ -61,7 +61,7 @@ pub fn expand_call(def: &mut Def) -> proc_macro2::TokenStream {
 		method.args.iter()
 			.map(|(is_compact, _, type_)| {
 				let final_type = if *is_compact {
-					quote::quote!(Compact<#type_>)
+					quote::quote_spanned!(type_.span() => Compact<#type_>)
 				} else {
 					quote::quote!(#type_)
 				};

frame/support/procedural/src/pallet/expand/constants.rs

@@ -33,9 +33,9 @@ struct ConstDef {
 /// * Impl fn module_constant_metadata for pallet.
 pub fn expand_constants(def: &mut Def) -> proc_macro2::TokenStream {
 	let frame_support = &def.frame_support;
-	let type_impl_gen = &def.type_impl_generics();
-	let type_decl_gen = &def.type_decl_generics();
-	let type_use_gen = &def.type_use_generics();
+	let type_impl_gen = &def.type_impl_generics(proc_macro2::Span::call_site());
+	let type_decl_gen = &def.type_decl_generics(proc_macro2::Span::call_site());
+	let type_use_gen = &def.type_use_generics(proc_macro2::Span::call_site());
 	let pallet_ident = &def.pallet_struct.pallet;
 
 	let mut where_clauses = vec![&def.config.where_clause];

frame/support/procedural/src/pallet/expand/error.rs

@@ -16,7 +16,6 @@
 // limitations under the License.
 
 use crate::pallet::Def;
-use syn::spanned::Spanned;
 
 /// * impl various trait on Error
 /// * impl ModuleErrorMetadata for Error
@@ -27,13 +26,11 @@ pub fn expand_error(def: &mut Def) -> proc_macro2::TokenStream {
 		return Default::default()
 	};
 
-	let error_item_span =
-		def.item.content.as_mut().expect("Checked by def parser").1[error.index].span();
 	let error_ident = &error.error;
 	let frame_support = &def.frame_support;
 	let frame_system = &def.frame_system;
-	let type_impl_gen = &def.type_impl_generics();
-	let type_use_gen = &def.type_use_generics();
+	let type_impl_gen = &def.type_impl_generics(error.attr_span);
+	let type_use_gen = &def.type_use_generics(error.attr_span);
 	let config_where_clause = &def.config.where_clause;
 
 	let phantom_variant: syn::Variant = syn::parse_quote!(
@@ -45,18 +42,20 @@ pub fn expand_error(def: &mut Def) -> proc_macro2::TokenStream {
 	);
 
 	let as_u8_matches = error.variants.iter().enumerate()
-		.map(|(i, (variant, _))| quote::quote!(Self::#variant => #i as u8,));
+		.map(|(i, (variant, _))| {
+			quote::quote_spanned!(error.attr_span => Self::#variant => #i as u8,)
+		});
 
 	let as_str_matches = error.variants.iter()
 		.map(|(variant, _)| {
 			let variant_str = format!("{}", variant);
-			quote::quote!(Self::#variant => #variant_str,)
+			quote::quote_spanned!(error.attr_span => Self::#variant => #variant_str,)
 		});
 
 	let metadata = error.variants.iter()
 		.map(|(variant, doc)| {
 			let variant_str = format!("{}", variant);
-			quote::quote!(
+			quote::quote_spanned!(error.attr_span =>
 				#frame_support::error::ErrorMetadata {
 					name: #frame_support::error::DecodeDifferent::Encode(#variant_str),
 					documentation: #frame_support::error::DecodeDifferent::Encode(&[ #( #doc, )* ]),
@@ -69,13 +68,13 @@ pub fn expand_error(def: &mut Def) -> proc_macro2::TokenStream {
 		if let syn::Item::Enum(item) = item {
 			item
 		} else {
-			unreachable!("Checked by event parser")
+			unreachable!("Checked by error parser")
 		}
 	};
 
 	error_item.variants.insert(0, phantom_variant);
 
-	quote::quote_spanned!(error_item_span =>
+	quote::quote_spanned!(error.attr_span =>
 		impl<#type_impl_gen> #frame_support::sp_std::fmt::Debug for #error_ident<#type_use_gen>
 			#config_where_clause
 		{

frame/support/procedural/src/pallet/expand/event.rs

@@ -16,7 +16,6 @@
 // limitations under the License.
 
 use crate::pallet::Def;
-use syn::spanned::Spanned;
 
 /// * Add __Ignore variant on Event
 /// * Impl various trait on Event including metadata
@@ -40,12 +39,12 @@ pub fn expand_event(def: &mut Def) -> proc_macro2::TokenStream {
 	let event_ident = &event.event;
 	let frame_system = &def.frame_system;
 	let frame_support = &def.frame_support;
-	let event_use_gen = &event.gen_kind.type_use_gen();
-	let event_impl_gen= &event.gen_kind.type_impl_gen();
+	let event_use_gen = &event.gen_kind.type_use_gen(event.attr_span);
+	let event_impl_gen= &event.gen_kind.type_impl_gen(event.attr_span);
 	let metadata = event.metadata.iter()
 		.map(|(ident, args, docs)| {
 			let name = format!("{}", ident);
-			quote::quote!(
+			quote::quote_spanned!(event.attr_span =>
 				#frame_support::event::EventMetadata {
 					name: #frame_support::event::DecodeDifferent::Encode(#name),
 					arguments: #frame_support::event::DecodeDifferent::Encode(&[
@@ -58,9 +57,6 @@ pub fn expand_event(def: &mut Def) -> proc_macro2::TokenStream {
 			)
 		});
 
-	let event_item_span =
-		def.item.content.as_mut().expect("Checked by def parser").1[event.index].span();
-
 	let event_item = {
 		let item = &mut def.item.content.as_mut().expect("Checked by def parser").1[event.index];
 		if let syn::Item::Enum(item) = item {
@@ -99,10 +95,10 @@ pub fn expand_event(def: &mut Def) -> proc_macro2::TokenStream {
 
 
 	let deposit_event = if let Some((fn_vis, fn_span)) = &event.deposit_event {
-		let event_use_gen = &event.gen_kind.type_use_gen();
-		let trait_use_gen = &def.trait_use_generics();
-		let type_impl_gen = &def.type_impl_generics();
-		let type_use_gen = &def.type_use_generics();
+		let event_use_gen = &event.gen_kind.type_use_gen(event.attr_span);
+		let trait_use_gen = &def.trait_use_generics(event.attr_span);
+		let type_impl_gen = &def.type_impl_generics(event.attr_span);
+		let type_use_gen = &def.type_use_generics(event.attr_span);
 
 		quote::quote_spanned!(*fn_span =>
 			impl<#type_impl_gen> Pallet<#type_use_gen> #completed_where_clause {
@@ -125,7 +121,7 @@ pub fn expand_event(def: &mut Def) -> proc_macro2::TokenStream {
 		Default::default()
 	};
 
-	quote::quote_spanned!(event_item_span =>
+	quote::quote_spanned!(event.attr_span =>
 		#deposit_event
 
 		impl<#event_impl_gen> From<#event_ident<#event_use_gen>> for () #event_where_clause {

frame/support/procedural/src/pallet/expand/genesis_build.rs

@@ -16,7 +16,6 @@
 // limitations under the License.
 
 use crate::pallet::Def;
-use syn::spanned::Spanned;
 
 /// * implement the trait `sp_runtime::BuildModuleGenesisStorage`
 /// * add #[cfg(features = "std")] to GenesisBuild implementation.
@@ -26,21 +25,21 @@ pub fn expand_genesis_build(def: &mut Def) -> proc_macro2::TokenStream {
 	} else {
 		return Default::default()
 	};
+	let genesis_build = def.genesis_build.as_ref().expect("Checked by def parser");
 
 	let frame_support = &def.frame_support;
-	let type_impl_gen = &def.type_impl_generics();
-	let type_use_gen = &def.type_use_generics();
+	let type_impl_gen = &def.type_impl_generics(genesis_build.attr_span);
+	let type_use_gen = &def.type_use_generics(genesis_build.attr_span);
 	let trait_use_gen = if def.config.has_instance {
-		quote::quote!(T, I)
+		quote::quote_spanned!(genesis_build.attr_span => T, I)
 	} else {
 		// `__InherentHiddenInstance` used by construct_runtime here is alias for `()`
-		quote::quote!(T, ())
+		quote::quote_spanned!(genesis_build.attr_span => T, ())
 	};
 	let gen_cfg_ident = &genesis_config.genesis_config;
 
-	let gen_cfg_use_gen = genesis_config.gen_kind.type_use_gen();
+	let gen_cfg_use_gen = genesis_config.gen_kind.type_use_gen(genesis_build.attr_span);
 
-	let genesis_build = def.genesis_build.as_ref().expect("Checked by def parser");
 	let genesis_build_item = &mut def.item.content.as_mut()
 		.expect("Checked by def parser").1[genesis_build.index];
 
@@ -53,7 +52,7 @@ pub fn expand_genesis_build(def: &mut Def) -> proc_macro2::TokenStream {
 	genesis_build_item_impl.attrs.push(syn::parse_quote!( #[cfg(feature = "std")] ));
 	let where_clause = &genesis_build.where_clause;
 
-	quote::quote_spanned!(genesis_build_item.span() =>
+	quote::quote_spanned!(genesis_build.attr_span =>
 		#[cfg(feature = "std")]
 		impl<#type_impl_gen> #frame_support::sp_runtime::BuildModuleGenesisStorage<#trait_use_gen>
 			for #gen_cfg_ident<#gen_cfg_use_gen> #where_clause

frame/support/procedural/src/pallet/expand/hooks.rs

@@ -16,21 +16,17 @@
 // limitations under the License.
 
 use crate::pallet::Def;
-use syn::spanned::Spanned;
 
 /// * implement the individual traits using the Hooks trait
 pub fn expand_hooks(def: &mut Def) -> proc_macro2::TokenStream {
 	let frame_support = &def.frame_support;
-	let type_impl_gen = &def.type_impl_generics();
-	let type_use_gen = &def.type_use_generics();
+	let type_impl_gen = &def.type_impl_generics(def.hooks.attr_span);
+	let type_use_gen = &def.type_use_generics(def.hooks.attr_span);
 	let pallet_ident = &def.pallet_struct.pallet;
 	let where_clause = &def.hooks.where_clause;
 	let frame_system = &def.frame_system;
 
-	let hooks_item_span = def.item.content.as_mut()
-		.expect("Checked by def parser").1[def.hooks.index].span();
-
-	quote::quote_spanned!(hooks_item_span =>
+	quote::quote_spanned!(def.hooks.attr_span =>
 		impl<#type_impl_gen>
 			#frame_support::traits::OnFinalize<<T as #frame_system::Config>::BlockNumber>
 			for #pallet_ident<#type_use_gen> #where_clause

frame/support/procedural/src/pallet/expand/pallet_struct.rs

@@ -25,9 +25,9 @@ use crate::pallet::Def;
 pub fn expand_pallet_struct(def: &mut Def) -> proc_macro2::TokenStream {
 	let frame_support = &def.frame_support;
 	let frame_system = &def.frame_system;
-	let type_impl_gen = &def.type_impl_generics();
-	let type_use_gen = &def.type_use_generics();
-	let type_decl_gen = &def.type_decl_generics();
+	let type_impl_gen = &def.type_impl_generics(def.pallet_struct.attr_span);
+	let type_use_gen = &def.type_use_generics(def.pallet_struct.attr_span);
+	let type_decl_gen = &def.type_decl_generics(def.pallet_struct.attr_span);
 	let pallet_ident = &def.pallet_struct.pallet;
 	let config_where_clause = &def.config.where_clause;
 
@@ -52,7 +52,7 @@ pub fn expand_pallet_struct(def: &mut Def) -> proc_macro2::TokenStream {
 
 	let module_error_metadata = if let Some(error_def) = &def.error {
 		let error_ident = &error_def.error;
-		quote::quote!(
+		quote::quote_spanned!(def.pallet_struct.attr_span =>
 			impl<#type_impl_gen> #frame_support::error::ModuleErrorMetadata
 				for #pallet_ident<#type_use_gen>
 				#config_where_clause
@@ -65,7 +65,7 @@ pub fn expand_pallet_struct(def: &mut Def) -> proc_macro2::TokenStream {
 			}
 		)
 	} else {
-		quote::quote!(
+		quote::quote_spanned!(def.pallet_struct.attr_span =>
 			impl<#type_impl_gen> #frame_support::error::ModuleErrorMetadata
 				for #pallet_ident<#type_use_gen>
 				#config_where_clause
@@ -77,7 +77,7 @@ pub fn expand_pallet_struct(def: &mut Def) -> proc_macro2::TokenStream {
 		)
 	};
 
-	quote::quote!(
+	quote::quote_spanned!(def.pallet_struct.attr_span =>
 		#module_error_metadata
 
 		/// Type alias to `Pallet`, to be used by `construct_runtime`.