Abstracts elections-phragmen pallet to use NposSolver (v2)

Cargo.toml

@@ -98,10 +98,9 @@ members = [
 	"frame/democracy",
 	"frame/fast-unstake",
 	"frame/try-runtime",
-	"frame/elections-phragmen",
+	"frame/elections",
 	"frame/election-provider-multi-phase",
 	"frame/election-provider-support",
-	"frame/election-provider-support/benchmarking",
 	"frame/election-provider-support/solution-type",
 	"frame/election-provider-support/solution-type/fuzzer",
 	"frame/examples/basic",

bin/node/runtime/Cargo.toml

@@ -69,8 +69,7 @@ pallet-conviction-voting = { version = "4.0.0-dev", default-features = false, pa
 pallet-core-fellowship = { version = "4.0.0-dev", default-features = false, path = "../../../frame/core-fellowship" }
 pallet-democracy = { version = "4.0.0-dev", default-features = false, path = "../../../frame/democracy" }
 pallet-election-provider-multi-phase = { version = "4.0.0-dev", default-features = false, path = "../../../frame/election-provider-multi-phase" }
-pallet-election-provider-support-benchmarking = { version = "4.0.0-dev", default-features = false, path = "../../../frame/election-provider-support/benchmarking", optional = true }
-pallet-elections-phragmen = { version = "5.0.0-dev", default-features = false, path = "../../../frame/elections-phragmen" }
+pallet-elections = { version = "5.0.0-dev", default-features = false, path = "../../../frame/elections" }
 pallet-fast-unstake = { version = "4.0.0-dev", default-features = false, path = "../../../frame/fast-unstake" }
 pallet-nis = { version = "4.0.0-dev", default-features = false, path = "../../../frame/nis" }
 pallet-grandpa = { version = "4.0.0-dev", default-features = false, path = "../../../frame/grandpa" }
@@ -129,7 +128,6 @@ with-tracing = ["frame-executive/with-tracing"]
 std = [
 	"pallet-whitelist/std",
 	"pallet-offences-benchmarking?/std",
-	"pallet-election-provider-support-benchmarking?/std",
 	"pallet-asset-tx-payment/std",
 	"frame-system-benchmarking?/std",
 	"frame-election-provider-support/std",
@@ -152,7 +150,7 @@ std = [
 	"pallet-conviction-voting/std",
 	"pallet-core-fellowship/std",
 	"pallet-democracy/std",
-	"pallet-elections-phragmen/std",
+	"pallet-elections/std",
 	"pallet-fast-unstake/std",
 	"frame-executive/std",
 	"pallet-nis/std",
@@ -228,6 +226,7 @@ runtime-benchmarks = [
 	"frame-benchmarking-pallet-pov/runtime-benchmarks",
 	"frame-support/runtime-benchmarks",
 	"frame-system/runtime-benchmarks",
+	"frame-election-provider-support/runtime-benchmarks",
 	"sp-runtime/runtime-benchmarks",
 	"pallet-alliance/runtime-benchmarks",
 	"pallet-assets/runtime-benchmarks",
@@ -242,8 +241,7 @@ runtime-benchmarks = [
 	"pallet-core-fellowship/runtime-benchmarks",
 	"pallet-democracy/runtime-benchmarks",
 	"pallet-election-provider-multi-phase/runtime-benchmarks",
-	"pallet-election-provider-support-benchmarking/runtime-benchmarks",
-	"pallet-elections-phragmen/runtime-benchmarks",
+	"pallet-elections/runtime-benchmarks",
 	"pallet-fast-unstake/runtime-benchmarks",
 	"pallet-nis/runtime-benchmarks",
 	"pallet-grandpa/runtime-benchmarks",
@@ -303,7 +301,7 @@ try-runtime = [
 	"pallet-core-fellowship/try-runtime",
 	"pallet-democracy/try-runtime",
 	"pallet-election-provider-multi-phase/try-runtime",
-	"pallet-elections-phragmen/try-runtime",
+	"pallet-elections/try-runtime",
 	"pallet-fast-unstake/try-runtime",
 	"pallet-nis/try-runtime",
 	"pallet-grandpa/try-runtime",

bin/node/runtime/src/lib.rs

@@ -24,7 +24,8 @@
 
 use codec::{Decode, Encode, MaxEncodedLen};
 use frame_election_provider_support::{
-	onchain, BalancingConfig, ElectionDataProvider, SequentialPhragmen, VoteWeight,
+	onchain, weights::SubstrateWeight, ApprovalVoting, BalancingConfig, ElectionDataProvider,
+	SequentialPhragmen, VoteWeight,
 };
 use frame_support::{
 	construct_runtime,
@@ -1025,18 +1026,21 @@ parameter_types! {
 	pub const TermDuration: BlockNumber = 7 * DAYS;
 	pub const DesiredMembers: u32 = 13;
 	pub const DesiredRunnersUp: u32 = 7;
-	pub const MaxVotesPerVoter: u32 = 16;
 	pub const MaxVoters: u32 = 512;
 	pub const MaxCandidates: u32 = 64;
-	pub const ElectionsPhragmenPalletId: LockIdentifier = *b"phrelect";
+	pub const MaxVotesPerVoter: u32 = 16;
+	// The ElectionsPalletId parameter name was changed along with the renaming of the elections
+	// pallet, but we keep the same lock ID to prevent a migration from current runtimes.
+	// Related to https://github.com/paritytech/substrate/issues/8250
+	pub const ElectionsPalletId: LockIdentifier = *b"phrelect";
 }
 
 // Make sure that there are no more than `MaxMembers` members elected via elections-phragmen.
 const_assert!(DesiredMembers::get() <= CouncilMaxMembers::get());
 
-impl pallet_elections_phragmen::Config for Runtime {
+impl pallet_elections::Config for Runtime {
 	type RuntimeEvent = RuntimeEvent;
-	type PalletId = ElectionsPhragmenPalletId;
+	type PalletId = ElectionsPalletId;
 	type Currency = Balances;
 	type ChangeMembers = Council;
 	// NOTE: this implies that council's genesis members cannot be set directly and must come from
@@ -1054,7 +1058,9 @@ impl pallet_elections_phragmen::Config for Runtime {
 	type MaxVoters = MaxVoters;
 	type MaxVotesPerVoter = MaxVotesPerVoter;
 	type MaxCandidates = MaxCandidates;
-	type WeightInfo = pallet_elections_phragmen::weights::SubstrateWeight<Runtime>;
+	type ElectionSolver = ApprovalVoting<Self::AccountId, Perbill>;
+	type SolverWeightInfo = SubstrateWeight<Runtime>;
+	type WeightInfo = pallet_elections::weights::SubstrateWeight<Runtime>;
 }
 
 parameter_types! {
@@ -1778,7 +1784,7 @@ construct_runtime!(
 		Democracy: pallet_democracy,
 		Council: pallet_collective::<Instance1>,
 		TechnicalCommittee: pallet_collective::<Instance2>,
-		Elections: pallet_elections_phragmen,
+		Elections: pallet_elections,
 		TechnicalMembership: pallet_membership::<Instance1>,
 		Grandpa: pallet_grandpa,
 		Treasury: pallet_treasury,
@@ -1895,6 +1901,7 @@ mod benches {
 	frame_benchmarking::define_benchmarks!(
 		[frame_benchmarking, BaselineBench::<Runtime>]
 		[frame_benchmarking_pallet_pov, Pov]
+		[frame_election_provider_support, EPSBench::<Runtime>]
 		[pallet_alliance, Alliance]
 		[pallet_assets, Assets]
 		[pallet_babe, Babe]
@@ -1908,8 +1915,7 @@ mod benches {
 		[pallet_core_fellowship, CoreFellowship]
 		[pallet_democracy, Democracy]
 		[pallet_election_provider_multi_phase, ElectionProviderMultiPhase]
-		[pallet_election_provider_support_benchmarking, EPSBench::<Runtime>]
-		[pallet_elections_phragmen, Elections]
+		[pallet_elections, Elections]
 		[pallet_fast_unstake, FastUnstake]
 		[pallet_nis, Nis]
 		[pallet_grandpa, Grandpa]
@@ -2390,7 +2396,7 @@ impl_runtime_apis! {
 			// which is why we need these two lines below.
 			use pallet_session_benchmarking::Pallet as SessionBench;
 			use pallet_offences_benchmarking::Pallet as OffencesBench;
-			use pallet_election_provider_support_benchmarking::Pallet as EPSBench;
+			use frame_election_provider_support::benchmarking::Pallet as EPSBench;
 			use frame_system_benchmarking::Pallet as SystemBench;
 			use baseline::Pallet as BaselineBench;
 			use pallet_nomination_pools_benchmarking::Pallet as NominationPoolsBench;
@@ -2413,14 +2419,14 @@ impl_runtime_apis! {
 			// which is why we need these two lines below.
 			use pallet_session_benchmarking::Pallet as SessionBench;
 			use pallet_offences_benchmarking::Pallet as OffencesBench;
-			use pallet_election_provider_support_benchmarking::Pallet as EPSBench;
+			use frame_election_provider_support::benchmarking::Pallet as EPSBench;
 			use frame_system_benchmarking::Pallet as SystemBench;
 			use baseline::Pallet as BaselineBench;
 			use pallet_nomination_pools_benchmarking::Pallet as NominationPoolsBench;
 
 			impl pallet_session_benchmarking::Config for Runtime {}
 			impl pallet_offences_benchmarking::Config for Runtime {}
-			impl pallet_election_provider_support_benchmarking::Config for Runtime {}
+			impl frame_election_provider_support::benchmarking::Config for Runtime {}
 			impl frame_system_benchmarking::Config for Runtime {}
 			impl baseline::Config for Runtime {}
 			impl pallet_nomination_pools_benchmarking::Config for Runtime {}

frame/election-provider-multi-phase/Cargo.toml

@@ -33,7 +33,6 @@ frame-election-provider-support = { version = "4.0.0-dev", default-features = fa
 
 # Optional imports for benchmarking
 frame-benchmarking = { version = "4.0.0-dev", default-features = false, path = "../benchmarking", optional = true }
-pallet-election-provider-support-benchmarking = { version = "4.0.0-dev", default-features = false, path = "../election-provider-support/benchmarking", optional = true }
 rand = { version = "0.8.5", default-features = false, features = ["alloc", "small_rng"], optional = true }
 strum = { version = "0.24.1",  default-features = false, features = ["derive"], optional = true }
 
@@ -50,7 +49,6 @@ frame-benchmarking = { version = "4.0.0-dev", path = "../benchmarking" }
 [features]
 default = ["std"]
 std = [
-	"pallet-election-provider-support-benchmarking?/std",
 	"codec/std",
 	"scale-info/std",
 	"log/std",