Offchain Phragmén BREAKING.

Cargo.toml

@@ -121,6 +121,7 @@ members = [
 	"primitives/offchain",
 	"primitives/panic-handler",
 	"primitives/phragmen",
+	"primitives/phragmen/compact",
 	"primitives/rpc",
 	"primitives/runtime-interface",
 	"primitives/runtime-interface/proc-macro",

bin/node/executor/tests/submit_transaction.rs

@@ -15,7 +15,7 @@
 // along with Substrate.  If not, see <http://www.gnu.org/licenses/>.
 
 use node_runtime::{
-	Call, Executive, Indices, Runtime, SubmitTransaction, UncheckedExtrinsic,
+	Call, Executive, Indices, Runtime, TransactionSubmitterOf, UncheckedExtrinsic,
 };
 use sp_application_crypto::AppKey;
 use sp_core::testing::KeyStore;
@@ -31,6 +31,8 @@ use codec::Decode;
 pub mod common;
 use self::common::*;
 
+type SubmitTransaction = TransactionSubmitterOf<pallet_im_online::sr25519::AuthorityId>;
+
 #[test]
 fn should_submit_unsigned_transaction() {
 	let mut t = new_test_ext(COMPACT_CODE, false);

bin/node/runtime/src/lib.rs

@@ -71,6 +71,51 @@ use constants::{time::*, currency::*};
 #[cfg(feature = "std")]
 include!(concat!(env!("OUT_DIR"), "/wasm_binary.rs"));
 
+/// A transaction submitter with the given key type.
+pub type TransactionSubmitterOf<KeyType> = TransactionSubmitter<KeyType, Runtime, UncheckedExtrinsic>;
+
+/// Submits transaction with the node's public and signature type. Adheres to the signed extension
+/// format of the chain.
+impl frame_system::offchain::CreateTransaction<Runtime, UncheckedExtrinsic> for Runtime {
+	type Public = <Signature as traits::Verify>::Signer;
+	type Signature = Signature;
+
+	fn create_transaction<TSigner: frame_system::offchain::Signer<Self::Public, Self::Signature>>(
+		call: Call,
+		public: Self::Public,
+		account: AccountId,
+		index: Index,
+	) -> Option<(Call, <UncheckedExtrinsic as traits::Extrinsic>::SignaturePayload)> {
+		// take the biggest period possible.
+		let period = BlockHashCount::get()
+			.checked_next_power_of_two()
+			.map(|c| c / 2)
+			.unwrap_or(2) as u64;
+		let current_block = System::block_number()
+			.saturated_into::<u64>()
+			// The `System::block_number` is initialized with `n+1`,
+			// so the actual block number is `n`.
+			.saturating_sub(1);
+		let tip = 0;
+		let extra: SignedExtra = (
+			frame_system::CheckVersion::<Runtime>::new(),
+			frame_system::CheckGenesis::<Runtime>::new(),
+			frame_system::CheckEra::<Runtime>::from(generic::Era::mortal(period, current_block)),
+			frame_system::CheckNonce::<Runtime>::from(index),
+			frame_system::CheckWeight::<Runtime>::new(),
+			pallet_transaction_payment::ChargeTransactionPayment::<Runtime>::from(tip),
+			Default::default(),
+		);
+		let raw_payload = SignedPayload::new(call, extra).map_err(|e| {
+			debug::warn!("Unable to create signed payload: {:?}", e);
+		}).ok()?;
+		let signature = TSigner::sign(public, &raw_payload)?;
+		let address = Indices::unlookup(account);
+		let (call, extra, _) = raw_payload.deconstruct();
+		Some((call, (address, signature, extra)))
+	}
+}
+
 /// Runtime version.
 pub const VERSION: RuntimeVersion = RuntimeVersion {
 	spec_name: create_runtime_str!("node"),
@@ -267,6 +312,7 @@ parameter_types! {
 	pub const BondingDuration: pallet_staking::EraIndex = 24 * 28;
 	pub const SlashDeferDuration: pallet_staking::EraIndex = 24 * 7; // 1/4 the bonding duration.
 	pub const RewardCurve: &'static PiecewiseLinear<'static> = &REWARD_CURVE;
+	pub const ElectionLookahead: BlockNumber = 150;
 }
 
 impl pallet_staking::Trait for Runtime {
@@ -284,6 +330,11 @@ impl pallet_staking::Trait for Runtime {
 	type SlashCancelOrigin = pallet_collective::EnsureProportionAtLeast<_3, _4, AccountId, CouncilCollective>;
 	type SessionInterface = Self;
 	type RewardCurve = RewardCurve;
+	type NextSessionChange = Babe;
+	type ElectionLookahead = ElectionLookahead;
+	type Call = Call;
+	type SubmitTransaction = TransactionSubmitterOf<Self::KeyType>;
+	type KeyType = pallet_babe::AuthorityId;
 }
 
 parameter_types! {
@@ -447,18 +498,15 @@ impl pallet_sudo::Trait for Runtime {
 	type Proposal = Call;
 }
 
-/// A runtime transaction submitter.
-pub type SubmitTransaction = TransactionSubmitter<ImOnlineId, Runtime, UncheckedExtrinsic>;
-
 parameter_types! {
 	pub const SessionDuration: BlockNumber = EPOCH_DURATION_IN_SLOTS as _;
 }
 
 impl pallet_im_online::Trait for Runtime {
-	type AuthorityId = ImOnlineId;
 	type Call = Call;
 	type Event = Event;
-	type SubmitTransaction = SubmitTransaction;
+	type AuthorityId = ImOnlineId;
+	type SubmitTransaction = TransactionSubmitterOf<Self::AuthorityId>;
 	type ReportUnresponsiveness = Offences;
 	type SessionDuration = SessionDuration;
 }
@@ -505,46 +553,6 @@ impl pallet_identity::Trait for Runtime {
 	type ForceOrigin = pallet_collective::EnsureProportionMoreThan<_1, _2, AccountId, CouncilCollective>;
 }
 
-impl frame_system::offchain::CreateTransaction<Runtime, UncheckedExtrinsic> for Runtime {
-	type Public = <Signature as traits::Verify>::Signer;
-	type Signature = Signature;
-
-	fn create_transaction<TSigner: frame_system::offchain::Signer<Self::Public, Self::Signature>>(
-		call: Call,
-		public: Self::Public,
-		account: AccountId,
-		index: Index,
-	) -> Option<(Call, <UncheckedExtrinsic as traits::Extrinsic>::SignaturePayload)> {
-		// take the biggest period possible.
-		let period = BlockHashCount::get()
-			.checked_next_power_of_two()
-			.map(|c| c / 2)
-			.unwrap_or(2) as u64;
-		let current_block = System::block_number()
-			.saturated_into::<u64>()
-			// The `System::block_number` is initialized with `n+1`,
-			// so the actual block number is `n`.
-			.saturating_sub(1);
-		let tip = 0;
-		let extra: SignedExtra = (
-			frame_system::CheckVersion::<Runtime>::new(),
-			frame_system::CheckGenesis::<Runtime>::new(),
-			frame_system::CheckEra::<Runtime>::from(generic::Era::mortal(period, current_block)),
-			frame_system::CheckNonce::<Runtime>::from(index),
-			frame_system::CheckWeight::<Runtime>::new(),
-			pallet_transaction_payment::ChargeTransactionPayment::<Runtime>::from(tip),
-			Default::default(),
-		);
-		let raw_payload = SignedPayload::new(call, extra).map_err(|e| {
-			debug::warn!("Unable to create signed payload: {:?}", e);
-		}).ok()?;
-		let signature = TSigner::sign(public, &raw_payload)?;
-		let address = Indices::unlookup(account);
-		let (call, extra, _) = raw_payload.deconstruct();
-		Some((call, (address, signature, extra)))
-	}
-}
-
 parameter_types! {
 	pub const ConfigDepositBase: Balance = 5 * DOLLARS;
 	pub const FriendDepositFactor: Balance = 50 * CENTS;
@@ -831,8 +839,8 @@ mod tests {
 			>,
 		{}
 
-		is_submit_signed_transaction::<SubmitTransaction>();
-		is_sign_and_submit_transaction::<SubmitTransaction>();
+		is_submit_signed_transaction::<TransactionSubmitterOf<ImOnlineId>>();
+		is_sign_and_submit_transaction::<TransactionSubmitterOf<ImOnlineId>>();
 	}
 
 	#[test]

frame/authority-discovery/src/lib.rs

@@ -103,7 +103,6 @@ mod tests {
 	use frame_support::{impl_outer_origin, parameter_types, weights::Weight};
 
 	type AuthorityDiscovery = Module<Test>;
-	type SessionIndex = u32;
 
 	#[derive(Clone, Eq, PartialEq)]
 	pub struct Test;

frame/babe/Cargo.toml

@@ -5,7 +5,6 @@ authors = ["Parity Technologies <[email protected]>"]
 edition = "2018"
 
 [dependencies]
-hex-literal = "0.2.1"
 codec = { package = "parity-scale-codec", version = "1.0.0", default-features = false, features = ["derive"] }
 serde = { version = "1.0.101", optional = true }
 sp-inherents = { version = "2.0.0", default-features = false, path = "../../primitives/inherents" }
@@ -21,11 +20,8 @@ sp-consensus-babe = { version = "0.8", default-features = false, path = "../../p
 sp-io ={ path = "../../primitives/io", default-features = false }
 
 [dev-dependencies]
-lazy_static = "1.4.0"
-parking_lot = "0.9.0"
 sp-version = { version = "2.0.0", default-features = false, path = "../../primitives/version" }
 sp-core = { version = "2.0.0", path = "../../primitives/core" }
-substrate-test-runtime = { version = "2.0.0", path = "../../test-utils/runtime" }
 
 [features]
 default = ["std"]

frame/babe/src/lib.rs

@@ -26,7 +26,7 @@ use sp_std::{result, prelude::*};
 use frame_support::{decl_storage, decl_module, traits::FindAuthor, traits::Get};
 use sp_timestamp::OnTimestampSet;
 use sp_runtime::{generic::DigestItem, ConsensusEngineId, Perbill};
-use sp_runtime::traits::{IsMember, SaturatedConversion, Saturating, RandomnessBeacon};
+use sp_runtime::traits::{IsMember, SaturatedConversion, Saturating, RandomnessBeacon, One, Bounded};
 use sp_staking::{
 	SessionIndex,
 	offence::{Offence, Kind},
@@ -305,12 +305,31 @@ impl<T: Trait> Module<T> {
 		// epoch 0 as having started at the slot of block 1. We want to use
 		// the same randomness and validator set as signalled in the genesis,
 		// so we don't rotate the epoch.
-		now != sp_runtime::traits::One::one() && {
+		now != One::one() && {
 			let diff = CurrentSlot::get().saturating_sub(Self::current_epoch_start());
 			diff >= T::EpochDuration::get()
 		}
 	}
 
+	/// Return the _best guess_ block number, at which the next epoch change is predicted to happen.
+	///
+	/// In other word, this is only accurate if no slots are missed. Given missed slots, the slot
+	/// number will grow while the block number will not. Hence, the result can be interpreted as an
+	/// upper bound.
+	///
+	/// -------------- IMPORTANT NOTE --------------
+	/// This implementation is linked to how [`should_epoch_change`] is working. This might need to
+	/// be updated accordingly, if the underlying mechanics of slot and epochs change.
+	pub fn next_expected_epoch_change(now: T::BlockNumber) -> T::BlockNumber {
+		let next_slot = Self::current_epoch_start().saturating_add(T::EpochDuration::get());
+		let slots_remaining = next_slot
+			.checked_sub(CurrentSlot::get())
+			.unwrap_or(Bounded::max_value());
+		// This is a best effort guess. Drifts in the slot/block ratio will cause errors here.
+		let blocks_remaining: T::BlockNumber = slots_remaining.saturated_into();
+		now.saturating_add(blocks_remaining)
+	}
+
 	/// DANGEROUS: Enact an epoch change. Should be done on every block where `should_epoch_change` has returned `true`,
 	/// and the caller is the only caller of this function.
 	///
@@ -322,10 +341,7 @@ impl<T: Trait> Module<T> {
 	) {
 		// PRECONDITION: caller has done initialization and is guaranteed
 		// by the session module to be called before this.
-		#[cfg(debug_assertions)]
-		{
-			assert!(Self::initialized().is_some())
-		}
+		debug_assert!(Self::initialized().is_some());
 
 		// Update epoch index
 		let epoch_index = EpochIndex::get()
@@ -471,6 +487,12 @@ impl<T: Trait> OnTimestampSet<T::Moment> for Module<T> {
 	fn on_timestamp_set(_moment: T::Moment) { }
 }
 
+impl<T: Trait> frame_support::traits::EstimateNextSessionChange<T::BlockNumber> for Module<T> {
+	fn estimate_next_session_change(now: T::BlockNumber) -> T::BlockNumber {
+		Self::next_expected_epoch_change(now)
+	}
+}
+
 impl<T: Trait> sp_runtime::BoundToRuntimeAppPublic for Module<T> {
 	type Public = AuthorityId;
 }