Collective: dynamic deposit based on number of proposals

cumulus/parachains/runtimes/collectives/collectives-westend/src/lib.rs

@@ -552,6 +552,9 @@ impl pallet_collective::Config<AllianceCollective> for Runtime {
 	type SetMembersOrigin = EnsureRoot<AccountId>;
 	type WeightInfo = weights::pallet_collective::WeightInfo<Runtime>;
 	type MaxProposalWeight = MaxProposalWeight;
+	type DisapproveOrigin = EnsureRoot<Self::AccountId>;
+	type KillOrigin = EnsureRoot<Self::AccountId>;
+	type Consideration = ();
 }
 
 pub const MAX_FELLOWS: u32 = ALLIANCE_MAX_MEMBERS;

prdoc/pr_3151.prdoc

@@ -0,0 +1,49 @@
+# Schema: Polkadot SDK PRDoc Schema (prdoc) v1.0.0
+# See doc at https://raw.githubusercontent.com/paritytech/polkadot-sdk/master/prdoc/schema_user.json
+
+title: Dynamic deposit based on number of proposals 
+
+doc:
+  - audience: 
+      - Runtime User
+      - Runtime Dev
+    description: |
+      Introduce a dynamic proposal deposit mechanism influenced by the total number of active 
+      proposals, with the option to set the deposit to none.
+
+      The potential cost (e.g., balance hold) for proposal submission and storage is determined 
+      by the implementation of the `Consideration` trait. The footprint is defined as `proposal_count`, 
+      representing the total number of active proposals in the system, excluding the one currently 
+      being proposed. This cost may vary based on the proposal count. The pallet also offers various 
+      types to define a cost strategy based on the number of proposals.
+
+      Two new calls are introduced:
+        - kill(origin, proposal_hash): the cancellation of a proposal, accompanied by the burning 
+        of the associated cost/consideration ticket.
+        - release_proposal_cost(origin, proposal_hash): the release of the cost for a non-active proposal.
+
+      New config parameters:
+        - DisapproveOrigin: origin from which a proposal in any status may be disapproved without 
+        associated cost for a proposer;
+        - KillOrigin: Origin from which any malicious proposal may be killed with associated cost 
+        for a proposer;
+        - Consideration: mechanism to assess the necessity of some cost for publishing and storing 
+        a proposal. Set to unit type to have not submission cost;
+
+      Additionally change: 
+        - benchmarks have been upgraded to benchmarks::v2 for collective pallet;
+        - `ensure_successful` function added to the `Consideration` under `runtime-benchmarks` feature.
+
+crates:
+  - name: pallet-collective
+    bump: major
+  - name: collectives-westend-runtime
+    bump: major
+  - name: kitchensink-runtime
+    bump: major
+  - name: pallet-alliance
+    bump: patch
+  - name: pallet-balances
+    bump: patch
+  - name: pallet-utility
+    bump: patch

substrate/bin/node/runtime/src/lib.rs

@@ -1114,6 +1114,9 @@ parameter_types! {
 	pub const CouncilMotionDuration: BlockNumber = 5 * DAYS;
 	pub const CouncilMaxProposals: u32 = 100;
 	pub const CouncilMaxMembers: u32 = 100;
+	pub const ProposalDepositOffset: Balance = ExistentialDeposit::get() + ExistentialDeposit::get();
+	pub const ProposalHoldReason: RuntimeHoldReason =
+		RuntimeHoldReason::Council(pallet_collective::HoldReason::ProposalSubmission);
 }
 
 type CouncilCollective = pallet_collective::Instance1;
@@ -1128,6 +1131,18 @@ impl pallet_collective::Config<CouncilCollective> for Runtime {
 	type WeightInfo = pallet_collective::weights::SubstrateWeight<Runtime>;
 	type SetMembersOrigin = EnsureRoot<Self::AccountId>;
 	type MaxProposalWeight = MaxCollectivesProposalWeight;
+	type DisapproveOrigin = EnsureRoot<Self::AccountId>;
+	type KillOrigin = EnsureRoot<Self::AccountId>;
+	type Consideration = HoldConsideration<
+		AccountId,
+		Balances,
+		ProposalHoldReason,
+		pallet_collective::deposit::Delayed<
+			ConstU32<2>,
+			pallet_collective::deposit::Linear<ConstU32<2>, ProposalDepositOffset>,
+		>,
+		u32,
+	>;
 }
 
 parameter_types! {
@@ -1189,6 +1204,9 @@ impl pallet_collective::Config<TechnicalCollective> for Runtime {
 	type WeightInfo = pallet_collective::weights::SubstrateWeight<Runtime>;
 	type SetMembersOrigin = EnsureRoot<Self::AccountId>;
 	type MaxProposalWeight = MaxCollectivesProposalWeight;
+	type DisapproveOrigin = EnsureRoot<Self::AccountId>;
+	type KillOrigin = EnsureRoot<Self::AccountId>;
+	type Consideration = ();
 }
 
 type EnsureRootOrHalfCouncil = EitherOfDiverse<
@@ -2027,6 +2045,9 @@ impl pallet_collective::Config<AllianceCollective> for Runtime {
 	type WeightInfo = pallet_collective::weights::SubstrateWeight<Runtime>;
 	type SetMembersOrigin = EnsureRoot<Self::AccountId>;
 	type MaxProposalWeight = MaxCollectivesProposalWeight;
+	type DisapproveOrigin = EnsureRoot<Self::AccountId>;
+	type KillOrigin = EnsureRoot<Self::AccountId>;
+	type Consideration = ();
 }
 
 parameter_types! {

substrate/frame/alliance/src/mock.rs

@@ -77,6 +77,9 @@ impl pallet_collective::Config<AllianceCollective> for Test {
 	type WeightInfo = ();
 	type SetMembersOrigin = EnsureRoot<Self::AccountId>;
 	type MaxProposalWeight = MaxProposalWeight;
+	type DisapproveOrigin = EnsureRoot<Self::AccountId>;
+	type KillOrigin = EnsureRoot<Self::AccountId>;
+	type Consideration = ();
 }
 
 parameter_types! {

substrate/frame/balances/src/tests/fungible_tests.rs

@@ -518,8 +518,9 @@ fn freeze_consideration_works() {
 			let who = 4;
 			// freeze amount taken somewhere outside of our (Consideration) scope.
 			let extend_freeze = 15;
-			let zero_ticket = Consideration::new(&who, Footprint::from_parts(0, 0)).unwrap();
-			assert!(zero_ticket.is_none());
+
+			let ticket = Consideration::new(&who, Footprint::from_parts(0, 0)).unwrap();
+			assert!(ticket.is_none());
 			assert_eq!(Balances::balance_frozen(&TestId::Foo, &who), 0);
 
 			let ticket = Consideration::new(&who, Footprint::from_parts(10, 1)).unwrap();
@@ -536,7 +537,6 @@ fn freeze_consideration_works() {
 
 			let ticket = ticket.update(&who, Footprint::from_parts(0, 0)).unwrap();
 			assert!(ticket.is_none());
-			assert_eq!(ticket, zero_ticket);
 			assert_eq!(Balances::balance_frozen(&TestId::Foo, &who), 0 + extend_freeze);
 
 			let ticket = Consideration::new(&who, Footprint::from_parts(10, 1)).unwrap();
@@ -565,11 +565,11 @@ fn hold_consideration_works() {
 			// hold amount taken somewhere outside of our (Consideration) scope.
 			let extend_hold = 15;
 
-			let zero_ticket = Consideration::new(&who, Footprint::from_parts(0, 0)).unwrap();
-			assert!(zero_ticket.is_none());
+			let ticket = Consideration::new(&who, Footprint::from_parts(0, 0)).unwrap();
+			assert!(ticket.is_none());
 			assert_eq!(Balances::balance_on_hold(&TestId::Foo, &who), 0);
 
-			let ticket = Consideration::new(&who, Footprint::from_parts(10, 1)).unwrap();
+			let ticket = ticket.update(&who, Footprint::from_parts(10, 1)).unwrap();
 			assert_eq!(Balances::balance_on_hold(&TestId::Foo, &who), 10);
 
 			let ticket = ticket.update(&who, Footprint::from_parts(4, 1)).unwrap();
@@ -583,7 +583,6 @@ fn hold_consideration_works() {
 
 			let ticket = ticket.update(&who, Footprint::from_parts(0, 0)).unwrap();
 			assert!(ticket.is_none());
-			assert_eq!(ticket, zero_ticket);
 			assert_eq!(Balances::balance_on_hold(&TestId::Foo, &who), 0 + extend_hold);
 
 			let ticket = Consideration::new(&who, Footprint::from_parts(10, 1)).unwrap();

substrate/frame/collective/Cargo.toml

@@ -17,15 +17,19 @@ targets = ["x86_64-unknown-linux-gnu"]
 
 [dependencies]
 codec = { features = ["derive"], workspace = true }
+docify = { workspace = true }
 log = { workspace = true }
 scale-info = { features = ["derive"], workspace = true }
 frame-benchmarking = { optional = true, workspace = true }
-frame-support = { workspace = true }
+frame-support = { features = ["experimental"], workspace = true }
 frame-system = { workspace = true }
 sp-core = { workspace = true }
 sp-io = { workspace = true }
 sp-runtime = { workspace = true }
 
+[dev-dependencies]
+pallet-balances = { workspace = true, default-features = false }
+
 [features]
 default = ["std"]
 std = [
@@ -34,6 +38,7 @@ std = [
 	"frame-support/std",
 	"frame-system/std",
 	"log/std",
+	"pallet-balances/std",
 	"scale-info/std",
 	"sp-core/std",
 	"sp-io/std",
@@ -43,10 +48,12 @@ runtime-benchmarks = [
 	"frame-benchmarking/runtime-benchmarks",
 	"frame-support/runtime-benchmarks",
 	"frame-system/runtime-benchmarks",
+	"pallet-balances/runtime-benchmarks",
 	"sp-runtime/runtime-benchmarks",
 ]
 try-runtime = [
 	"frame-support/try-runtime",
 	"frame-system/try-runtime",
+	"pallet-balances/try-runtime",
 	"sp-runtime/try-runtime",
 ]