pallet-vesting: Support multiple, merge-able vesting schedules

bin/node/runtime/src/lib.rs

@@ -1062,6 +1062,9 @@ impl pallet_vesting::Config for Runtime {
 	type BlockNumberToBalance = ConvertInto;
 	type MinVestedTransfer = MinVestedTransfer;
 	type WeightInfo = pallet_vesting::weights::SubstrateWeight<Runtime>;
+	// `VestingInfo` encode length is 36bytes. 28 schedules gets encoded as 1009 bytes, which is the
+	// highest number of schedules that encodes less than 2^10.
+	const MAX_VESTING_SCHEDULES: u32 = 28;
 }
 
 impl pallet_mmr::Config for Runtime {

frame/support/src/traits/tokens/currency/lockable.rs

@@ -80,8 +80,8 @@ pub trait VestingSchedule<AccountId> {
 
 	/// Adds a vesting schedule to a given account.
 	///
-	/// If there already exists a vesting schedule for the given account, an `Err` is returned
-	/// and nothing is updated.
+	/// If the account has `MaxVestingSchedules`, an Error is returned and nothing
+	/// is updated.
 	///
 	/// Is a no-op if the amount to be vested is zero.
 	///
@@ -93,8 +93,16 @@ pub trait VestingSchedule<AccountId> {
 		starting_block: Self::Moment,
 	) -> DispatchResult;
 
+	/// Checks if `add_vesting_schedule` would work against `who`.
+	fn can_add_vesting_schedule(
+		who: &AccountId,
+		locked: <Self::Currency as Currency<AccountId>>::Balance,
+		per_block: <Self::Currency as Currency<AccountId>>::Balance,
+		starting_block: Self::Moment,
+	) -> DispatchResult;
+
 	/// Remove a vesting schedule for a given account.
 	///
 	/// NOTE: This doesn't alter the free balance of the account.
-	fn remove_vesting_schedule(who: &AccountId);
+	fn remove_vesting_schedule(who: &AccountId, schedule_index: u32) -> DispatchResult;
 }

frame/vesting/Cargo.toml

@@ -21,9 +21,10 @@ sp-runtime = { version = "4.0.0-dev", default-features = false, path = "../../pr
 frame-support = { version = "4.0.0-dev", default-features = false, path = "../support" }
 frame-system = { version = "4.0.0-dev", default-features = false, path = "../system" }
 frame-benchmarking = { version = "4.0.0-dev", default-features = false, path = "../benchmarking", optional = true }
+log = { version = "0.4.0", default-features = false  }
 
 [dev-dependencies]
-sp-io = { version = "4.0.0-dev", path = "../../primitives/io" }
+sp-io = { version = "4.0.0-dev", default-features = false, path = "../../primitives/io" }
 sp-core = { version = "4.0.0-dev", path = "../../primitives/core" }
 pallet-balances = { version = "4.0.0-dev", path = "../balances" }