Companion for paritytech/parity-bridges-common#1613

primitives/runtime/src/lib.rs

@@ -45,7 +45,8 @@ use num_traits::{CheckedSub, One};
 use scale_info::TypeInfo;
 // paritytech
 use frame_support::{
-	log, pallet_prelude::DispatchResult, PalletError, RuntimeDebug, StorageHasher, StorageValue,
+	log, pallet_prelude::DispatchResult, weights::Weight, PalletError, RuntimeDebug, StorageHasher,
+	StorageValue,
 };
 use frame_system::RawOrigin;
 use sp_core::{storage::StorageKey, H256};
@@ -486,6 +487,24 @@ pub fn storage_value_key(pallet_prefix: &str, value_name: &str) -> StorageKey {
 	StorageKey(final_key)
 }
 
+/// All extra operations with weights that we need in bridges.
+pub trait WeightExtraOps {
+	/// Checked division of individual components of two weights.
+	///
+	/// Divides components and returns minimal division result. Returns `None` if one
+	/// of `other` weight components is zero.
+	fn min_components_checked_div(&self, other: Weight) -> Option<u64>;
+}
+
+impl WeightExtraOps for Weight {
+	fn min_components_checked_div(&self, other: Weight) -> Option<u64> {
+		Some(sp_std::cmp::min(
+			self.ref_time().checked_div(other.ref_time())?,
+			self.proof_size().checked_div(other.proof_size())?,
+		))
+	}
+}
+
 #[cfg(test)]
 mod tests {
 	use super::*;