Enforce stricter rustfmt rules to prevent style ambiguity (#10939)

by default rustfmt preserve local style, and Claude loves to add semi or
bracket where there were none before,
We should make the formatting more strict as this is a bit annoying to
remind it constantly not to make unnecessary diff.

## Summary

The PR is just updating
https://github.com/paritytech/polkadot-sdk/blob/pg/stricter-rustfmt-rules/.rustfmt.toml
every other changes are just the result of running the linter


- Change `match_arm_leading_pipes` from "Preserve" to "Never" to enforce
a single style
- Change `trailing_semicolon` from false to true to enforce `return 42;`
false unfortunately preserve the local style
- Add `normalize_comments = true` to normalize comment spacing (e.g.,
`// comment` not `//comment`)
- Add `normalize_doc_attributes = true` to enforce `///` over `#[doc =
""]`

These changes ensure only one valid formatting style exists, reducing
unnecessary diffs in pull requests caused by different but equally valid
formatting styles.

## Not changed (for now)
The following options also default to "Preserve" but were intentionally
not changed due to (even) larger diff impact:

- `group_imports` - Would enforce import grouping order (std → external
→ crate) but causes massive import reordering across the codebase
- `hex_literal_case` - Would enforce `0xABCD` vs `0xabcd` consistency
- edition 2024 - not sure what that change but it also probably create a
big diff

These could be considered in a future PR if the one-time diff cost is
acceptable.

---------

Co-authored-by: cmd[bot] <41898282+github-actions[bot]@users.noreply.github.com>

Author: pgherveou

.rustfmt.toml

@@ -8,16 +8,18 @@ imports_granularity = "Crate"
 reorder_imports = true
 # Consistency
 newline_style = "Unix"
+normalize_comments = true
+normalize_doc_attributes = true
 # Misc
 chain_width = 80
 spaces_around_ranges = false
 binop_separator = "Back"
 reorder_impl_items = false
-match_arm_leading_pipes = "Preserve"
+match_arm_leading_pipes = "Never"
 match_arm_blocks = false
 match_block_trailing_comma = true
 trailing_comma = "Vertical"
-trailing_semicolon = false
+trailing_semicolon = true
 use_field_init_shorthand = true
 # Format comments
 comment_width = 100

bridges/bin/runtime-common/src/extensions.rs

@@ -105,7 +105,7 @@ where
 			has_failed || !SubmitFinalityProofHelper::<T, I>::was_successful(bundled_block_number);
 
 		if !has_failed {
-			return
+			return;
 		}
 
 		// let's slash registered relayer
@@ -176,7 +176,7 @@ where
 			!SubmitParachainHeadsHelper::<T, ParachainsInstance>::was_successful(&update);
 
 		if !has_failed {
-			return
+			return;
 		}
 
 		// let's slash registered relayer
@@ -465,7 +465,7 @@ mod tests {
 		type ToPostDispatch = u64;
 		fn validate(_who: &u64, call: &MockCall) -> (u64, TransactionValidity) {
 			if call.data <= 1 {
-				return (1, InvalidTransaction::Custom(1).into())
+				return (1, InvalidTransaction::Custom(1).into());
 			}
 
 			(1, Ok(ValidTransaction { priority: 1, ..Default::default() }))
@@ -493,7 +493,7 @@ mod tests {
 		type ToPostDispatch = u64;
 		fn validate(_who: &u64, call: &MockCall) -> (u64, TransactionValidity) {
 			if call.data <= 2 {
-				return (2, InvalidTransaction::Custom(2).into())
+				return (2, InvalidTransaction::Custom(2).into());
 			}
 
 			(2, Ok(ValidTransaction { priority: 2, ..Default::default() }))

bridges/bin/runtime-common/src/messages_benchmarking.rs

@@ -48,7 +48,7 @@ fn prepare_inbound_message<LaneId>(
 
 	// if we don't need a correct message, then we may just return some random blob
 	if !params.is_successful_dispatch_expected {
-		return vec![0u8; expected_size]
+		return vec![0u8; expected_size];
 	}
 
 	// else let's prepare successful message.

bridges/modules/beefy/src/utils.rs

@@ -75,7 +75,7 @@ fn verify_signatures<T: Config<I>, I: 'static>(
 			if authority.verify(sig, &msg) {
 				missing_signatures = missing_signatures.saturating_sub(1);
 				if missing_signatures == 0 {
-					break
+					break;
 				}
 			} else {
 				tracing::debug!(

bridges/modules/grandpa/src/call_ext.rs

@@ -154,7 +154,7 @@ impl<T: Config<I>, I: 'static> SubmitFinalityProofHelper<T, I> {
 					"Cannot finalize obsolete header"
 				);
 
-				return Err(Error::<T, I>::OldHeader)
+				return Err(Error::<T, I>::OldHeader);
 			},
 		};
 
@@ -168,7 +168,7 @@ impl<T: Config<I>, I: 'static> SubmitFinalityProofHelper<T, I> {
 					"Cannot finalize header signed by unknown authority set"
 				);
 
-				return Err(Error::<T, I>::InvalidAuthoritySetId)
+				return Err(Error::<T, I>::InvalidAuthoritySetId);
 			}
 		}
 
@@ -200,7 +200,7 @@ pub trait CallSubType<T: Config<I, RuntimeCall = Self>, I: 'static>:
 				justification,
 				None,
 				false,
-			))
+			));
 		} else if let Some(crate::Call::<T, I>::submit_finality_proof_ex {
 			finality_target,
 			justification,
@@ -213,7 +213,7 @@ pub trait CallSubType<T: Config<I, RuntimeCall = Self>, I: 'static>:
 				justification,
 				Some(*current_set_id),
 				*is_free_execution_expected,
-			))
+			));
 		}
 
 		None
@@ -243,7 +243,7 @@ pub trait CallSubType<T: Config<I, RuntimeCall = Self>, I: 'static>:
 		};
 
 		if Pallet::<T, I>::ensure_not_halted().is_err() {
-			return Err(InvalidTransaction::Call.into())
+			return Err(InvalidTransaction::Call.into());
 		}
 
 		let result = SubmitFinalityProofHelper::<T, I>::check_obsolete_from_extension(&call_info);

bridges/modules/messages/src/benchmarking.rs

@@ -191,7 +191,6 @@ impl<T: Config<I>, I: 'static> ReceiveMessagesProofSetup<T, I> {
 mod benchmarks {
 	use super::*;
 
-	//
 	// Benchmarks that are used directly by the runtime calls weight formulae.
 	//
 
@@ -501,7 +500,6 @@ mod benchmarks {
 		assert!(T::is_relayer_rewarded(&relayer2_id));
 	}
 
-	//
 	// Benchmarks that the runtime developers may use for proper pallet configuration.
 	//
 

bridges/modules/messages/src/call_ext.rs

@@ -54,7 +54,7 @@ impl<T: Config<I>, I: 'static> CallHelper<T, I> {
 					// so if relayer slots are released, then message slots are also
 					// released
 					return post_occupation.free_message_slots >
-						info.unrewarded_relayers.free_message_slots
+						info.unrewarded_relayers.free_message_slots;
 				}
 
 				inbound_lane_data.last_delivered_nonce() == *info.base.bundled_range.end()
@@ -131,7 +131,7 @@ impl<
 					best_stored_nonce: inbound_lane_data.last_delivered_nonce(),
 				},
 				unrewarded_relayers: unrewarded_relayers_occupation::<T, I>(&inbound_lane_data),
-			})
+			});
 		}
 
 		None
@@ -157,19 +157,19 @@ impl<
 				bundled_range: outbound_lane_data.latest_received_nonce + 1..=
 					relayers_state.last_delivered_nonce,
 				best_stored_nonce: outbound_lane_data.latest_received_nonce,
-			}))
+			}));
 		}
 
 		None
 	}
 
 	fn call_info(&self) -> Option<MessagesCallInfo<T::LaneId>> {
 		if let Some(info) = self.receive_messages_proof_info() {
-			return Some(MessagesCallInfo::ReceiveMessagesProof(info))
+			return Some(MessagesCallInfo::ReceiveMessagesProof(info));
 		}
 
 		if let Some(info) = self.receive_messages_delivery_proof_info() {
-			return Some(MessagesCallInfo::ReceiveMessagesDeliveryProof(info))
+			return Some(MessagesCallInfo::ReceiveMessagesDeliveryProof(info));
 		}
 
 		None
@@ -195,7 +195,7 @@ impl<
 					"Rejecting messages transaction on halted pallet"
 				);
 
-				return sp_runtime::transaction_validity::InvalidTransaction::Call.into()
+				return sp_runtime::transaction_validity::InvalidTransaction::Call.into();
 			},
 			Some(MessagesCallInfo::ReceiveMessagesProof(proof_info))
 				if proof_info
@@ -207,7 +207,7 @@ impl<
 					"Rejecting obsolete messages delivery transaction"
 				);
 
-				return sp_runtime::transaction_validity::InvalidTransaction::Stale.into()
+				return sp_runtime::transaction_validity::InvalidTransaction::Stale.into();
 			},
 			Some(MessagesCallInfo::ReceiveMessagesDeliveryProof(proof_info))
 				if proof_info.is_obsolete() =>
@@ -218,7 +218,7 @@ impl<
 					"Rejecting obsolete messages confirmation transaction"
 				);
 
-				return sp_runtime::transaction_validity::InvalidTransaction::Stale.into()
+				return sp_runtime::transaction_validity::InvalidTransaction::Stale.into();
 			},
 			_ => {},
 		}

bridges/modules/messages/src/inbound_lane.rs

@@ -151,10 +151,10 @@ impl<S: InboundLaneStorage> InboundLane<S> {
 
 		if outbound_lane_data.latest_received_nonce > last_delivered_nonce {
 			// this is something that should never happen if proofs are correct
-			return None
+			return None;
 		}
 		if outbound_lane_data.latest_received_nonce <= data.last_confirmed_nonce {
-			return None
+			return None;
 		}
 
 		let new_confirmed_nonce = outbound_lane_data.latest_received_nonce;
@@ -191,18 +191,18 @@ impl<S: InboundLaneStorage> InboundLane<S> {
 	) -> ReceptionResult<Dispatch::DispatchLevelResult> {
 		let mut data = self.storage.data();
 		if Some(nonce) != data.last_delivered_nonce().checked_add(1) {
-			return ReceptionResult::InvalidNonce
+			return ReceptionResult::InvalidNonce;
 		}
 
 		// if there are more unrewarded relayer entries than we may accept, reject this message
 		if data.relayers.len() as MessageNonce >= self.storage.max_unrewarded_relayer_entries() {
-			return ReceptionResult::TooManyUnrewardedRelayers
+			return ReceptionResult::TooManyUnrewardedRelayers;
 		}
 
 		// if there are more unconfirmed messages than we may accept, reject this message
 		let unconfirmed_messages_count = nonce.saturating_sub(data.last_confirmed_nonce);
 		if unconfirmed_messages_count > self.storage.max_unconfirmed_messages() {
-			return ReceptionResult::TooManyUnconfirmedMessages
+			return ReceptionResult::TooManyUnconfirmedMessages;
 		}
 
 		// then, dispatch message

bridges/modules/messages/src/outbound_lane.rs

@@ -142,10 +142,10 @@ impl<S: OutboundLaneStorage> OutboundLane<S> {
 			end: latest_delivered_nonce,
 		};
 		if confirmed_messages.total_messages() == 0 {
-			return Ok(None)
+			return Ok(None);
 		}
 		if confirmed_messages.end > data.latest_generated_nonce {
-			return Err(ReceptionConfirmationError::FailedToConfirmFutureMessages)
+			return Err(ReceptionConfirmationError::FailedToConfirmFutureMessages);
 		}
 		if confirmed_messages.total_messages() > max_allowed_messages {
 			// that the relayer has declared correct number of messages that the proof contains (it
@@ -159,7 +159,7 @@ impl<S: OutboundLaneStorage> OutboundLane<S> {
 				max_allowed=%max_allowed_messages,
 				"Messages delivery proof contains too many messages to confirm"
 			);
-			return Err(ReceptionConfirmationError::TryingToConfirmMoreMessagesThanExpected)
+			return Err(ReceptionConfirmationError::TryingToConfirmMoreMessagesThanExpected);
 		}
 
 		ensure_unrewarded_relayers_are_correct(confirmed_messages.end, relayers)?;
@@ -203,18 +203,18 @@ fn ensure_unrewarded_relayers_are_correct<RelayerId>(
 		// unrewarded relayer entry must have at least 1 unconfirmed message
 		// (guaranteed by the `InboundLane::receive_message()`)
 		if entry.messages.end < entry.messages.begin {
-			return Err(ReceptionConfirmationError::EmptyUnrewardedRelayerEntry)
+			return Err(ReceptionConfirmationError::EmptyUnrewardedRelayerEntry);
 		}
 		// every entry must confirm range of messages that follows previous entry range
 		// (guaranteed by the `InboundLane::receive_message()`)
 		if expected_entry_begin != Some(entry.messages.begin) {
-			return Err(ReceptionConfirmationError::NonConsecutiveUnrewardedRelayerEntries)
+			return Err(ReceptionConfirmationError::NonConsecutiveUnrewardedRelayerEntries);
 		}
 		expected_entry_begin = entry.messages.end.checked_add(1);
 		// entry can't confirm messages larger than `inbound_lane_data.latest_received_nonce()`
 		// (guaranteed by the `InboundLane::receive_message()`)
 		if entry.messages.end > latest_received_nonce {
-			return Err(ReceptionConfirmationError::FailedToConfirmFutureMessages)
+			return Err(ReceptionConfirmationError::FailedToConfirmFutureMessages);
 		}
 	}
 

bridges/modules/messages/src/proofs.rs

@@ -65,7 +65,7 @@ pub fn verify_messages_proof<T: Config<I>, I: 'static>(
 	// receiving proofs where end < begin is ok (if proof includes outbound lane state)
 	let messages_in_the_proof = nonces_range.saturating_len();
 	if messages_in_the_proof != MessageNonce::from(messages_count) {
-		return Err(VerificationError::MessagesCountMismatch)
+		return Err(VerificationError::MessagesCountMismatch);
 	}
 
 	// Read messages first. All messages that are claimed to be in the proof must
@@ -92,7 +92,7 @@ pub fn verify_messages_proof<T: Config<I>, I: 'static>(
 
 	// Now we may actually check if the proof is empty or not.
 	if proved_lane_messages.lane_state.is_none() && proved_lane_messages.messages.is_empty() {
-		return Err(VerificationError::EmptyMessageProof)
+		return Err(VerificationError::EmptyMessageProof);
 	}
 
 	// Check that the storage proof doesn't have any untouched keys.