pallet macro: always generate storage info on pallet struct (#9246)

* always implement storage info on Pallet

* fix UI test

* Fold span computation into trait and method computation

Co-authored-by: Keith Yeung <kungfukeith11@gmail.com>

substrate/frame/support/test/tests/pallet.rs

@@ -397,6 +397,9 @@ pub mod pallet2 {
 	{
 	}
 
+	#[pallet::storage]
+	pub type SomeValue<T: Config> = StorageValue<_, Vec<u32>>;
+
 	#[pallet::event]
 	pub enum Event {
 		/// Something
@@ -1247,4 +1250,15 @@ fn test_storage_info() {
 			},
 		],
 	);
+
+	assert_eq!(
+		Example2::storage_info(),
+		vec![
+			StorageInfo {
+				prefix: prefix(b"Example2", b"SomeValue"),
+				max_values: Some(1),
+				max_size: None,
+			},
+		],
+	);
 }

substrate/frame/support/test/tests/pallet_ui/storage_ensure_span_are_ok_on_wrong_gen.stderr

@@ -31,3 +31,37 @@ error[E0277]: the trait bound `Bar: WrapperTypeEncode` is not satisfied
    = note: required because of the requirements on the impl of `FullCodec` for `Bar`
    = note: required because of the requirements on the impl of `StorageValueMetadata` for `frame_support::pallet_prelude::StorageValue<_GeneratedPrefixForStorageFoo<T>, Bar>`
    = note: required by `frame_support::storage::types::StorageValueMetadata::NAME`
+
+error[E0277]: the trait bound `Bar: WrapperTypeDecode` is not satisfied
+ --> $DIR/storage_ensure_span_are_ok_on_wrong_gen.rs:9:12
+  |
+9 |     #[pallet::pallet]
+  |               ^^^^^^ the trait `WrapperTypeDecode` is not implemented for `Bar`
+  |
+  = note: required because of the requirements on the impl of `Decode` for `Bar`
+  = note: required because of the requirements on the impl of `FullCodec` for `Bar`
+  = note: required because of the requirements on the impl of `PartialStorageInfoTrait` for `frame_support::pallet_prelude::StorageValue<_GeneratedPrefixForStorageFoo<T>, Bar>`
+  = note: required by `partial_storage_info`
+
+error[E0277]: the trait bound `Bar: EncodeLike` is not satisfied
+ --> $DIR/storage_ensure_span_are_ok_on_wrong_gen.rs:9:12
+  |
+9 |     #[pallet::pallet]
+  |               ^^^^^^ the trait `EncodeLike` is not implemented for `Bar`
+  |
+  = note: required because of the requirements on the impl of `FullEncode` for `Bar`
+  = note: required because of the requirements on the impl of `FullCodec` for `Bar`
+  = note: required because of the requirements on the impl of `PartialStorageInfoTrait` for `frame_support::pallet_prelude::StorageValue<_GeneratedPrefixForStorageFoo<T>, Bar>`
+  = note: required by `partial_storage_info`
+
+error[E0277]: the trait bound `Bar: WrapperTypeEncode` is not satisfied
+ --> $DIR/storage_ensure_span_are_ok_on_wrong_gen.rs:9:12
+  |
+9 |     #[pallet::pallet]
+  |               ^^^^^^ the trait `WrapperTypeEncode` is not implemented for `Bar`
+  |
+  = note: required because of the requirements on the impl of `pallet::_::_parity_scale_codec::Encode` for `Bar`
+  = note: required because of the requirements on the impl of `FullEncode` for `Bar`
+  = note: required because of the requirements on the impl of `FullCodec` for `Bar`
+  = note: required because of the requirements on the impl of `PartialStorageInfoTrait` for `frame_support::pallet_prelude::StorageValue<_GeneratedPrefixForStorageFoo<T>, Bar>`
+  = note: required by `partial_storage_info`

substrate/frame/support/test/tests/pallet_ui/storage_ensure_span_are_ok_on_wrong_gen_unnamed.stderr

@@ -31,3 +31,37 @@ error[E0277]: the trait bound `Bar: WrapperTypeEncode` is not satisfied
    = note: required because of the requirements on the impl of `FullCodec` for `Bar`
    = note: required because of the requirements on the impl of `StorageValueMetadata` for `frame_support::pallet_prelude::StorageValue<_GeneratedPrefixForStorageFoo<T>, Bar>`
    = note: required by `frame_support::storage::types::StorageValueMetadata::NAME`
+
+error[E0277]: the trait bound `Bar: WrapperTypeDecode` is not satisfied
+ --> $DIR/storage_ensure_span_are_ok_on_wrong_gen_unnamed.rs:9:12
+  |
+9 |     #[pallet::pallet]
+  |               ^^^^^^ the trait `WrapperTypeDecode` is not implemented for `Bar`
+  |
+  = note: required because of the requirements on the impl of `Decode` for `Bar`
+  = note: required because of the requirements on the impl of `FullCodec` for `Bar`
+  = note: required because of the requirements on the impl of `PartialStorageInfoTrait` for `frame_support::pallet_prelude::StorageValue<_GeneratedPrefixForStorageFoo<T>, Bar>`
+  = note: required by `partial_storage_info`
+
+error[E0277]: the trait bound `Bar: EncodeLike` is not satisfied
+ --> $DIR/storage_ensure_span_are_ok_on_wrong_gen_unnamed.rs:9:12
+  |
+9 |     #[pallet::pallet]
+  |               ^^^^^^ the trait `EncodeLike` is not implemented for `Bar`
+  |
+  = note: required because of the requirements on the impl of `FullEncode` for `Bar`
+  = note: required because of the requirements on the impl of `FullCodec` for `Bar`
+  = note: required because of the requirements on the impl of `PartialStorageInfoTrait` for `frame_support::pallet_prelude::StorageValue<_GeneratedPrefixForStorageFoo<T>, Bar>`
+  = note: required by `partial_storage_info`
+
+error[E0277]: the trait bound `Bar: WrapperTypeEncode` is not satisfied
+ --> $DIR/storage_ensure_span_are_ok_on_wrong_gen_unnamed.rs:9:12
+  |
+9 |     #[pallet::pallet]
+  |               ^^^^^^ the trait `WrapperTypeEncode` is not implemented for `Bar`
+  |
+  = note: required because of the requirements on the impl of `pallet::_::_parity_scale_codec::Encode` for `Bar`
+  = note: required because of the requirements on the impl of `FullEncode` for `Bar`
+  = note: required because of the requirements on the impl of `FullCodec` for `Bar`
+  = note: required because of the requirements on the impl of `PartialStorageInfoTrait` for `frame_support::pallet_prelude::StorageValue<_GeneratedPrefixForStorageFoo<T>, Bar>`
+  = note: required by `partial_storage_info`