diff --git a/substrate/frame/support/procedural/src/pallet/expand/constants.rs b/substrate/frame/support/procedural/src/pallet/expand/constants.rs
index 57fa8b7f3cd9af0e24feffaac17367b7cc817054..d7fbb5a718973c9d2a9ed9f32ab384536265f3d6 100644
--- a/substrate/frame/support/procedural/src/pallet/expand/constants.rs
+++ b/substrate/frame/support/procedural/src/pallet/expand/constants.rs
@@ -30,8 +30,7 @@ struct ConstDef {
pub metadata_name: Option<syn::Ident>,
}
-///
-/// * Impl fn module_constant_metadata for pallet.
+/// Implement the `pallet_constants_metadata` function for the 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(proc_macro2::Span::call_site());
diff --git a/substrate/frame/support/procedural/src/pallet/parse/config.rs b/substrate/frame/support/procedural/src/pallet/parse/config.rs
index 406072df4b9d60b874df83578c12df5df1216329..eaeaab247588052a36d7aac469935b62151fa013 100644
--- a/substrate/frame/support/procedural/src/pallet/parse/config.rs
+++ b/substrate/frame/support/procedural/src/pallet/parse/config.rs
@@ -94,30 +94,26 @@ impl TryFrom<&syn::TraitItemType> for ConstMetadataDef {
let bound = trait_ty
.bounds
.iter()
- .find_map(|b| {
- if let syn::TypeParamBound::Trait(tb) = b {
- tb.path
- .segments
- .last()
- .and_then(|s| if s.ident == "Get" { Some(s) } else { None })
- } else {
- None
- }
+ .find_map(|param_bound| {
+ let syn::TypeParamBound::Trait(trait_bound) = param_bound else { return None };
+
+ trait_bound.path.segments.last().and_then(|s| (s.ident == "Get").then(|| s))
})
.ok_or_else(|| err(trait_ty.span(), "`Get<T>` trait bound not found"))?;
- let type_arg = if let syn::PathArguments::AngleBracketed(ref ab) = bound.arguments {
- if ab.args.len() == 1 {
- if let syn::GenericArgument::Type(ref ty) = ab.args[0] {
- Ok(ty)
- } else {
- Err(err(ab.args[0].span(), "Expected a type argument"))
- }
- } else {
- Err(err(bound.span(), "Expected a single type argument"))
- }
- } else {
- Err(err(bound.span(), "Expected trait generic args"))
- }?;
+
+ let syn::PathArguments::AngleBracketed(ref ab) = bound.arguments else {
+ return Err(err(bound.span(), "Expected trait generic args"))
+ };
+
+ // Only one type argument is expected.
+ if ab.args.len() != 1 {
+ return Err(err(bound.span(), "Expected a single type argument"))
+ }
+
+ let syn::GenericArgument::Type(ref type_arg) = ab.args[0] else {
+ return Err(err(ab.args[0].span(), "Expected a type argument"))
+ };
+
let type_ = syn::parse2::<syn::Type>(replace_self_by_t(type_arg.to_token_stream()))
.expect("Internal error: replacing `Self` by `T` should result in valid type");
@@ -223,55 +219,55 @@ fn check_event_type(
trait_item: &syn::TraitItem,
trait_has_instance: bool,
) -> syn::Result<bool> {
- if let syn::TraitItem::Type(type_) = trait_item {
- if type_.ident == "RuntimeEvent" {
- // Check event has no generics
- if !type_.generics.params.is_empty() || type_.generics.where_clause.is_some() {
- let msg = "Invalid `type RuntimeEvent`, associated type `RuntimeEvent` is reserved and must have\
- no generics nor where_clause";
- return Err(syn::Error::new(trait_item.span(), msg))
- }
+ let syn::TraitItem::Type(type_) = trait_item else { return Ok(false) };
- // Check bound contains IsType and From
- let has_is_type_bound = type_.bounds.iter().any(|s| {
- syn::parse2::<IsTypeBoundEventParse>(s.to_token_stream())
- .map_or(false, |b| has_expected_system_config(b.0, frame_system))
- });
-
- if !has_is_type_bound {
- let msg = "Invalid `type RuntimeEvent`, associated type `RuntimeEvent` is reserved and must \
- bound: `IsType<<Self as frame_system::Config>::RuntimeEvent>`".to_string();
- return Err(syn::Error::new(type_.span(), msg))
- }
+ if type_.ident != "RuntimeEvent" {
+ return Ok(false)
+ }
- let from_event_bound = type_
- .bounds
- .iter()
- .find_map(|s| syn::parse2::<FromEventParse>(s.to_token_stream()).ok());
+ // Check event has no generics
+ if !type_.generics.params.is_empty() || type_.generics.where_clause.is_some() {
+ let msg =
+ "Invalid `type RuntimeEvent`, associated type `RuntimeEvent` is reserved and must have\
+ no generics nor where_clause";
+ return Err(syn::Error::new(trait_item.span(), msg))
+ }
- let from_event_bound = if let Some(b) = from_event_bound {
- b
- } else {
- let msg = "Invalid `type RuntimeEvent`, associated type `RuntimeEvent` is reserved and must \
- bound: `From<Event>` or `From<Event<Self>>` or `From<Event<Self, I>>`";
- return Err(syn::Error::new(type_.span(), msg))
- };
+ // Check bound contains IsType and From
+ let has_is_type_bound = type_.bounds.iter().any(|s| {
+ syn::parse2::<IsTypeBoundEventParse>(s.to_token_stream())
+ .map_or(false, |b| has_expected_system_config(b.0, frame_system))
+ });
+
+ if !has_is_type_bound {
+ let msg =
+ "Invalid `type RuntimeEvent`, associated type `RuntimeEvent` is reserved and must \
+ bound: `IsType<<Self as frame_system::Config>::RuntimeEvent>`"
+ .to_string();
+ return Err(syn::Error::new(type_.span(), msg))
+ }
- if from_event_bound.is_generic && (from_event_bound.has_instance != trait_has_instance)
- {
- let msg = "Invalid `type RuntimeEvent`, associated type `RuntimeEvent` bounds inconsistent \
+ let from_event_bound = type_
+ .bounds
+ .iter()
+ .find_map(|s| syn::parse2::<FromEventParse>(s.to_token_stream()).ok());
+
+ let Some(from_event_bound) = from_event_bound else {
+ let msg =
+ "Invalid `type RuntimeEvent`, associated type `RuntimeEvent` is reserved and must \
+ bound: `From<Event>` or `From<Event<Self>>` or `From<Event<Self, I>>`";
+ return Err(syn::Error::new(type_.span(), msg))
+ };
+
+ if from_event_bound.is_generic && (from_event_bound.has_instance != trait_has_instance) {
+ let msg =
+ "Invalid `type RuntimeEvent`, associated type `RuntimeEvent` bounds inconsistent \
`From<Event..>`. Config and generic Event must be both with instance or \
without instance";
- return Err(syn::Error::new(type_.span(), msg))
- }
-
- Ok(true)
- } else {
- Ok(false)
- }
- } else {
- Ok(false)
+ return Err(syn::Error::new(type_.span(), msg))
}
+
+ Ok(true)
}
/// Check that the path to `frame_system::Config` is valid, this is that the path is just
@@ -334,9 +330,7 @@ impl ConfigDef {
item: &mut syn::Item,
enable_default: bool,
) -> syn::Result<Self> {
- let item = if let syn::Item::Trait(item) = item {
- item
- } else {
+ let syn::Item::Trait(item) = item else {
let msg = "Invalid pallet::config, expected trait definition";
return Err(syn::Error::new(item.span(), msg))
};
diff --git a/substrate/frame/support/procedural/src/pallet/parse/helper.rs b/substrate/frame/support/procedural/src/pallet/parse/helper.rs
index 3187c9139c8f46c7664e96edb6870f68979146ae..d4f58a4c56df8ba61e26535cc19287f336e78846 100644
--- a/substrate/frame/support/procedural/src/pallet/parse/helper.rs
+++ b/substrate/frame/support/procedural/src/pallet/parse/helper.rs
@@ -55,16 +55,16 @@ pub(crate) fn take_first_item_pallet_attr<Attr>(
where
Attr: syn::parse::Parse,
{
- let attrs = if let Some(attrs) = item.mut_item_attrs() { attrs } else { return Ok(None) };
+ let Some(attrs) = item.mut_item_attrs() else { return Ok(None) };
- if let Some(index) = attrs.iter().position(|attr| {
+ let Some(index) = attrs.iter().position(|attr| {
attr.path().segments.first().map_or(false, |segment| segment.ident == "pallet")
- }) {
- let pallet_attr = attrs.remove(index);
- Ok(Some(syn::parse2(pallet_attr.into_token_stream())?))
- } else {
- Ok(None)
- }
+ }) else {
+ return Ok(None)
+ };
+
+ let pallet_attr = attrs.remove(index);
+ Ok(Some(syn::parse2(pallet_attr.into_token_stream())?))
}
/// Take all the pallet attributes (e.g. attribute like `#[pallet..]`) and decode them to `Attr`