Allow pallet error enum variants to contain fields (#10242)

* Allow pallet errors to contain at most one field * Update docs on pallet::error * Reword documentation * cargo fmt * Introduce CompactPalletError trait and require #[pallet::error] fields to implement them * cargo fmt * Do not assume tuple variants * Add CompactPalletError derive macro * Check for error type compactness in construct_runtime * cargo fmt * Derive CompactPalletError instead of implementing it directly during macro expansion * Implement CompactPalletError on OptionBool instead of Option<bool> * Check for type idents instead of variant ident * Add doc comments for ErrorCompactnessTest * Add an trait implementation of ErrorCompactnessTest for () * Convert the error field of DispatchError to a 4-element byte array * Add static check for pallet error size * Rename to MAX_PALLET_ERROR_ENCODED_SIZE * Remove ErrorCompactnessTest trait * Remove check_compactness * Return only the most significant byte when constructing a custom InvalidTransaction * Rename CompactPalletError to PalletError * Use counter to generate unique idents for assert macros * Make declarative pallet macros compile with pallet error size checks * Remove unused doc comment * Try and fix build errors * Fix build errors * Add macro_use for some test modules * Test fix * Fix compilation errors * Remove unneeded #[macro_use] * Resolve import ambiguity * Make path to pallet Error enum more specific * Fix test expectation * Disambiguate imports * Fix test expectations * Revert appending pallet module name to path * Rename bags_list::list::Error to BagError * Fixes * Fixes * Fixes * Fix test expectations * Fix test expectation * Add more implementations for PalletError * Lift the 1-field requirement for nested pallet errors * Fix UI test expectation * Remove PalletError impl for OptionBool * Use saturating operations * cargo fmt * Delete obsolete test * Fix test expectation * Try and use assert macro in const context * Pull out the pallet error size check macro * Fix UI test for const assertion * cargo fmt * Apply clippy suggestion * Fix doc comment * Docs for create_tt_return_macro * Ensure TryInto is imported in earlier Rust editions * Apply suggestions from code review Co-authored-by: Bastian Köcher <bkchr@users.noreply.github.com> * Fix up comments and names * Implement PalletError for Never * cargo fmt * Don't compile example code * Bump API version for block builder * Factor in codec attributes while derving PalletError * Rename module and fix unit test * Add missing attribute * Check API version and convert ApplyExtrinsicResult accordingly * Rename BagError to ListError Co-authored-by: Kian Paimani <5588131+kianenigma@users.noreply.github.com> * Use codec crate re-exported from frame support * Add links to types mentioned in doc comments Co-authored-by: Bastian Köcher <bkchr@users.noreply.github.com> * cargo fmt * cargo fmt * Re-add attribute for hidden docs Co-authored-by: Bastian Köcher <bkchr@users.noreply.github.com> Co-authored-by: Kian Paimani <5588131+kianenigma@users.noreply.github.com>
2026-04-30 14:17:56 +00:00 · 2022-03-24 09:11:14 +01:00
parent 5c9f23af13
commit 208be86934
38 changed files with 1263 additions and 241 deletions
@@ -0,0 +1,95 @@
+// This file is part of Substrate.
+
+// Copyright (C) 2022 Parity Technologies (UK) Ltd.
+// SPDX-License-Identifier: Apache-2.0
+
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// 	http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+//! Traits for describing and constraining pallet error types.
+use codec::{Compact, Decode, Encode};
+use sp_std::marker::PhantomData;
+
+/// Trait indicating that the implementing type is going to be included as a field in a variant of
+/// the `#[pallet::error]` enum type.
+///
+/// ## Notes
+///
+/// The pallet error enum has a maximum encoded size as defined by
+/// [`frame_support::MAX_MODULE_ERROR_ENCODED_SIZE`]. If the pallet error type exceeds this size
+/// limit, a static assertion during compilation will fail. The compilation error will be in the
+/// format of `error[E0080]: evaluation of constant value failed` due to the usage of
+/// const assertions.
+pub trait PalletError: Encode + Decode {
+	/// The maximum encoded size for the implementing type.
+	///
+	/// This will be used to check whether the pallet error type is less than or equal to
+	/// [`frame_support::MAX_MODULE_ERROR_ENCODED_SIZE`], and if it is, a compilation error will be
+	/// thrown.
+	const MAX_ENCODED_SIZE: usize;
+}
+
+macro_rules! impl_for_types {
+	(size: $size:expr, $($typ:ty),+) => {
+		$(
+			impl PalletError for $typ {
+				const MAX_ENCODED_SIZE: usize = $size;
+			}
+		)+
+	};
+}
+
+impl_for_types!(size: 0, (), crate::Never);
+impl_for_types!(size: 1, u8, i8, bool);
+impl_for_types!(size: 2, u16, i16, Compact<u8>);
+impl_for_types!(size: 4, u32, i32, Compact<u16>);
+impl_for_types!(size: 5, Compact<u32>);
+impl_for_types!(size: 8, u64, i64);
+impl_for_types!(size: 9, Compact<u64>);
+// Contains a u64 for secs and u32 for nanos, hence 12 bytes
+impl_for_types!(size: 12, core::time::Duration);
+impl_for_types!(size: 16, u128, i128);
+impl_for_types!(size: 17, Compact<u128>);
+
+impl<T> PalletError for PhantomData<T> {
+	const MAX_ENCODED_SIZE: usize = 0;
+}
+
+impl<T: PalletError> PalletError for core::ops::Range<T> {
+	const MAX_ENCODED_SIZE: usize = T::MAX_ENCODED_SIZE.saturating_mul(2);
+}
+
+impl<T: PalletError, const N: usize> PalletError for [T; N] {
+	const MAX_ENCODED_SIZE: usize = T::MAX_ENCODED_SIZE.saturating_mul(N);
+}
+
+impl<T: PalletError> PalletError for Option<T> {
+	const MAX_ENCODED_SIZE: usize = T::MAX_ENCODED_SIZE.saturating_add(1);
+}
+
+impl<T: PalletError, E: PalletError> PalletError for Result<T, E> {
+	const MAX_ENCODED_SIZE: usize = if T::MAX_ENCODED_SIZE > E::MAX_ENCODED_SIZE {
+		T::MAX_ENCODED_SIZE
+	} else {
+		E::MAX_ENCODED_SIZE
+	}
+	.saturating_add(1);
+}
+
+#[impl_trait_for_tuples::impl_for_tuples(1, 18)]
+impl PalletError for Tuple {
+	const MAX_ENCODED_SIZE: usize = {
+		let mut size = 0_usize;
+		for_tuples!( #(size = size.saturating_add(Tuple::MAX_ENCODED_SIZE);)* );
+		size
+	};
+}