Aura and Slots refactoring (paritytech#8386)

* Make slot duration being exposed as `Duration` to the outside

* Some slot info love

* Add `build_aura_worker` utility function

* Copy copy copy

client/consensus/aura/src/lib.rs

@@ -111,12 +111,12 @@ impl SlotCompatible for AuraSlotCompatible {
 	fn extract_timestamp_and_slot(
 		&self,
 		data: &InherentData,
-	) -> Result<(u64, AuraInherent, std::time::Duration), sp_consensus::Error> {
+	) -> Result<(sp_timestamp::Timestamp, AuraInherent, std::time::Duration), sp_consensus::Error> {
 		data.timestamp_inherent_data()
 			.and_then(|t| data.aura_inherent_data().map(|a| (t, a)))
 			.map_err(Into::into)
 			.map_err(sp_consensus::Error::InherentData)
-			.map(|(x, y)| (*x, y, Default::default()))
+			.map(|(x, y)| (x, y, Default::default()))
 	}
 }
 

client/consensus/babe/src/lib.rs

@@ -919,13 +919,13 @@ impl SlotCompatible for TimeSource {
 	fn extract_timestamp_and_slot(
 		&self,
 		data: &InherentData,
-	) -> Result<(u64, Slot, std::time::Duration), sp_consensus::Error> {
+	) -> Result<(sp_timestamp::Timestamp, Slot, std::time::Duration), sp_consensus::Error> {
 		trace!(target: "babe", "extract timestamp");
 		data.timestamp_inherent_data()
 			.and_then(|t| data.babe_inherent_data().map(|a| (t, a)))
 			.map_err(Into::into)
 			.map_err(sp_consensus::Error::InherentData)
-			.map(|(x, y)| (*x, y, self.0.lock().0.take().unwrap_or_default()))
+			.map(|(x, y)| (x, y, self.0.lock().0.take().unwrap_or_default()))
 	}
 }
 

primitives/consensus/aura/src/inherents.rs

@@ -88,7 +88,7 @@ impl ProvideInherentData for InherentDataProvider {
 		use sp_timestamp::TimestampInherentData;
 
 		let timestamp = inherent_data.timestamp_inherent_data()?;
-		let slot = *timestamp / self.slot_duration;
+		let slot = *timestamp / self.slot_duration.as_millis() as u64;
 		inherent_data.put_data(INHERENT_IDENTIFIER, &slot)
 	}
 

primitives/consensus/babe/src/inherents.rs

@@ -83,7 +83,7 @@ impl ProvideInherentData for InherentDataProvider {
 
 	fn provide_inherent_data(&self, inherent_data: &mut InherentData) -> Result<(), Error> {
 		let timestamp = inherent_data.timestamp_inherent_data()?;
-		let slot = *timestamp / self.slot_duration;
+		let slot = *timestamp / self.slot_duration.as_millis() as u64;
 		inherent_data.put_data(INHERENT_IDENTIFIER, &slot)
 	}
 

primitives/timestamp/src/lib.rs

@@ -44,6 +44,11 @@ impl Timestamp {
 	pub const fn new(inner: u64) -> Self {
 		Self(inner)
 	}
+
+	/// Returns `self` as [`Duration`].
+	pub fn as_duration(&self) -> Duration {
+		Duration::from_millis(self.0)
+	}
 }
 
 impl sp_std::ops::Deref for Timestamp {
@@ -101,8 +106,8 @@ impl From<Timestamp> for u64 {
 	}
 }
 
-impl From<sp_std::time::Duration> for Timestamp {
-	fn from(duration: sp_std::time::Duration) -> Self {
+impl From<Duration> for Timestamp {
+	fn from(duration: Duration) -> Self {
 		Timestamp(duration.as_millis() as u64)
 	}
 }