Child bounties comments (#11053)

* * formatting
* use uniform notion of parent and child, no "master" or "general" entity
* README updated to match comments
* `parent_index` used over simply `index`

* rm `parent_*` change

* parent_bounty_id

* parent_index rm

* fmt

* Apply suggestions from code review

substrate/frame/bounties/README.md

@@ -2,28 +2,38 @@
 
 ## Bounty
 
-**Note :: This pallet is tightly coupled with pallet-treasury**
+> NOTE: This pallet is tightly coupled with pallet-treasury.
 
-A Bounty Spending is a reward for a specified body of work - or specified set of objectives - that
+A Bounty Spending is a reward for a specified body of work - or specified set of objectives -
-needs to be executed for a predefined Treasury amount to be paid out. A curator is assigned after
+that needs to be executed for a predefined Treasury amount to be paid out. A curator is assigned
-the bounty is approved and funded by Council, to be delegated with the responsibility of assigning a
+after the bounty is approved and funded by Council, to be delegated with the responsibility of
-payout address once the specified set of objectives is completed.
+assigning a payout address once the specified set of objectives is completed.
 
-After the Council has activated a bounty, it delegates the work that requires expertise to a curator
+After the Council has activated a bounty, it delegates the work that requires expertise to a
-in exchange of a deposit. Once the curator accepts the bounty, they get to close the active bounty.
+curator in exchange of a deposit. Once the curator accepts the bounty, they get to close the
-Closing the active bounty enacts a delayed payout to the payout address, the curator fee and the
+active bounty. Closing the active bounty enacts a delayed payout to the payout address, the
-return of the curator deposit. The delay allows for intervention through regular democracy. The
+curator fee and the return of the curator deposit. The delay allows for intervention through
-Council gets to unassign the curator, resulting in a new curator election. The Council also gets to
+regular democracy. The Council gets to unassign the curator, resulting in a new curator
-cancel the bounty if deemed necessary before assigning a curator or once the bounty is active or
+election. The Council also gets to cancel the bounty if deemed necessary before assigning a
-payout is pending, resulting in the slash of the curator's deposit.
+curator or once the bounty is active or payout is pending, resulting in the slash of the
+curator's deposit.
+
+This pallet may opt into using a [`ChildBountyManager`] that enables bounties to be split into
+sub-bounties, as children of anh established bounty (called the parent in the context of it's
+children).
+
+> NOTE: The parent bounty cannot be closed if it has a non-zero number of it has active child
+> bounties associated with it.
 
 ### Terminology
 
-- **Bounty spending proposal:** A proposal to reward a predefined body of work upon completion by
+Bounty:
-  the Treasury.
+
+- **Bounty spending proposal:** A proposal to reward a predefined body of work upon completion
+  by the Treasury.
 - **Proposer:** An account proposing a bounty spending.
-- **Curator:** An account managing the bounty and assigning a payout address receiving the reward
+- **Curator:** An account managing the bounty and assigning a payout address receiving the
-  for the completion of work.
+  reward for the completion of work.
 - **Deposit:** The amount held on deposit for placing a bounty proposal plus the amount held on
   deposit per byte within the bounty description.
 - **Curator deposit:** The payment from a candidate willing to curate an approved bounty. The
@@ -31,7 +41,8 @@ payout is pending, resulting in the slash of the curator's deposit.
 - **Bounty value:** The total amount that should be paid to the Payout Address if the bounty is
   rewarded.
 - **Payout address:** The account to which the total or part of the bounty is assigned to.
-- **Payout Delay:** The delay period for which a bounty beneficiary needs to wait before claiming.
+- **Payout Delay:** The delay period for which a bounty beneficiary needs to wait before
+  claiming.
 - **Curator fee:** The reserved upfront payment for a curator for work related to the bounty.
 
 ## Interface
@@ -39,6 +50,7 @@ payout is pending, resulting in the slash of the curator's deposit.
 ### Dispatchable Functions
 
 Bounty protocol:
+
 - `propose_bounty` - Propose a specific treasury amount to be earmarked for a predefined set of
   tasks and stake the required deposit.
 - `approve_bounty` - Accept a specific treasury amount to be earmarked for a predefined body of

substrate/frame/bounties/src/lib.rs

@@ -35,10 +35,17 @@
 //! curator or once the bounty is active or payout is pending, resulting in the slash of the
 //! curator's deposit.
 //!
+//! This pallet may opt into using a [`ChildBountyManager`] that enables bounties to be split into
+//! sub-bounties, as children of anh established bounty (called the parent in the context of it's
+//! children).
+//!
+//! > NOTE: The parent bounty cannot be closed if it has a non-zero number of it has active child
+//! > bounties associated with it.
 //!
 //! ### Terminology
 //!
 //! Bounty:
+//!
 //! - **Bounty spending proposal:** A proposal to reward a predefined body of work upon completion
 //!   by the Treasury.
 //! - **Proposer:** An account proposing a bounty spending.
@@ -60,6 +67,7 @@
 //! ### Dispatchable Functions
 //!
 //! Bounty protocol:
+//!
 //! - `propose_bounty` - Propose a specific treasury amount to be earmarked for a predefined set of
 //!   tasks and stake the required deposit.
 //! - `approve_bounty` - Accept a specific treasury amount to be earmarked for a predefined body of
@@ -165,9 +173,9 @@ pub enum BountyStatus<AccountId, BlockNumber> {
 	},
 }
 
-/// The child-bounty manager.
+/// The child bounty manager.
 pub trait ChildBountyManager<Balance> {
-	/// Get the active child-bounties for a parent bounty.
+	/// Get the active child bounties for a parent bounty.
 	fn child_bounties_count(bounty_id: BountyIndex) -> BountyIndex;
 
 	/// Get total curator fees of children-bounty curators.
@@ -231,7 +239,7 @@ pub mod pallet {
 		/// Weight information for extrinsics in this pallet.
 		type WeightInfo: WeightInfo;
 
-		/// The child-bounty manager.
+		/// The child bounty manager.
 		type ChildBountyManager: ChildBountyManager<BalanceOf<Self>>;
 	}
 
@@ -256,7 +264,7 @@ pub mod pallet {
 		PendingPayout,
 		/// The bounties cannot be claimed/closed because it's still in the countdown period.
 		Premature,
-		/// The bounty cannot be closed because it has active child-bounties.
+		/// The bounty cannot be closed because it has active child bounties.
 		HasActiveChildBounty,
 		/// Too many approvals are already queued.
 		TooManyQueued,
@@ -552,7 +560,7 @@ pub mod pallet {
 			Bounties::<T>::try_mutate_exists(bounty_id, |maybe_bounty| -> DispatchResult {
 				let mut bounty = maybe_bounty.as_mut().ok_or(Error::<T>::InvalidIndex)?;
 
-				// Ensure no active child-bounties before processing the call.
+				// Ensure no active child bounties before processing the call.
 				ensure!(
 					T::ChildBountyManager::child_bounties_count(bounty_id) == 0,
 					Error::<T>::HasActiveChildBounty
@@ -610,8 +618,8 @@ pub mod pallet {
 					let err_amount = T::Currency::unreserve(&curator, bounty.curator_deposit);
 					debug_assert!(err_amount.is_zero());
 
-					// Get total child-bounties curator fees, and subtract it from master curator
+					// Get total child bounties curator fees, and subtract it from the parent
-					// fee.
+					// curator fee (the fee in present referenced bounty, `self`).
 					let children_fee = T::ChildBountyManager::children_curator_fees(bounty_id);
 					debug_assert!(children_fee <= fee);
 
@@ -663,7 +671,7 @@ pub mod pallet {
 				|maybe_bounty| -> DispatchResultWithPostInfo {
 					let bounty = maybe_bounty.as_ref().ok_or(Error::<T>::InvalidIndex)?;
 
-					// Ensure no active child-bounties before processing the call.
+					// Ensure no active child bounties before processing the call.
 					ensure!(
 						T::ChildBountyManager::child_bounties_count(bounty_id) == 0,
 						Error::<T>::HasActiveChildBounty

substrate/frame/child-bounties/README.md

@@ -1,21 +1,29 @@
-# Child Bounties Pallet (pallet-child-bounties)
+# Child Bounties Pallet ( `pallet-child-bounties` )
 
 ## Child Bounty
 
-> NOTE: This pallet is tightly coupled with pallet-treasury and pallet-bounties.
+> NOTE: This pallet is tightly coupled with `pallet-treasury` and `pallet-bounties`.
 
-With child bounties, a large bounty proposal can be divided into smaller chunks, for parallel execution, and for efficient governance and tracking of spent funds.
+With child bounties, a large bounty proposal can be divided into smaller chunks,
-
+for parallel execution, and for efficient governance and tracking of spent funds.
-A child-bounty is a smaller piece of work, extracted from a parent bounty. A curator is assigned after the child-bounty is created by the parent bounty curator, to be delegated with the responsibility of assigning a payout address once the specified set of tasks is completed.
+A child bounty is a smaller piece of work, extracted from a parent bounty.
+A curator is assigned after the child bounty is created by the parent bounty curator,
+to be delegated with the responsibility of assigning a payout address once 
+the specified set of tasks is completed.
 
 ## Interface
 
 ### Dispatchable Functions
 
-- `add_child_bounty` - Add a child-bounty for a parent-bounty to for dividing the work in smaller tasks.
+Child Bounty protocol:
-- `propose_curator` - Assign an account to a child-bounty as candidate curator.
+
-- `accept_curator` - Accept a child-bounty assignment from the parent-bounty curator, setting a curator deposit.
+- `add_child_bounty` - Add a child bounty for a parent bounty to for dividing the work in
+  smaller tasks.
+- `propose_curator` - Assign an account to a child bounty as candidate curator.
+- `accept_curator` - Accept a child bounty assignment from the parent bounty curator,
+  setting a curator deposit.
 - `award_child_bounty` - Close and pay out the specified amount for the completed work.
-- `claim_child_bounty` - Claim a specific child-bounty amount from the payout address.
+- `claim_child_bounty` - Claim a specific child bounty amount from the payout address.
-- `unassign_curator` - Unassign an accepted curator from a specific child-bounty.
+- `unassign_curator` - Unassign an accepted curator from a specific child bounty.
-- `close_child_bounty` - Cancel the child-bounty for a specific treasury amount and close the bounty.
+- `close_child_bounty` - Cancel the child bounty for a specific treasury amount
+  and close the bounty.

substrate/frame/child-bounties/src/lib.rs

@@ -15,16 +15,16 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-//! # Child Bounties Pallet ( pallet-child-bounties )
+//! # Child Bounties Pallet ( `pallet-child-bounties` )
 //!
 //! ## Child Bounty
 //!
-//! > NOTE: This pallet is tightly coupled with pallet-treasury and pallet-bounties.
+//! > NOTE: This pallet is tightly coupled with `pallet-treasury` and `pallet-bounties`.
 //!
 //! With child bounties, a large bounty proposal can be divided into smaller chunks,
 //! for parallel execution, and for efficient governance and tracking of spent funds.
-//! A child-bounty is a smaller piece of work, extracted from a parent bounty.
+//! A child bounty is a smaller piece of work, extracted from a parent bounty.
-//! A curator is assigned after the child-bounty is created by the parent bounty curator,
+//! A curator is assigned after the child bounty is created by the parent bounty curator,
 //! to be delegated with the responsibility of assigning a payout address once the specified
 //! set of tasks is completed.
 //!
@@ -33,22 +33,22 @@
 //! ### Dispatchable Functions
 //!
 //! Child Bounty protocol:
-//! - `add_child_bounty` - Add a child-bounty for a parent-bounty to for dividing the work in
+//! - `add_child_bounty` - Add a child bounty for a parent bounty to for dividing the work in
 //!   smaller tasks.
-//! - `propose_curator` - Assign an account to a child-bounty as candidate curator.
+//! - `propose_curator` - Assign an account to a child bounty as candidate curator.
-//! - `accept_curator` - Accept a child-bounty assignment from the parent-bounty curator, setting a
+//! - `accept_curator` - Accept a child bounty assignment from the parent bounty curator, setting a
 //!   curator deposit.
 //! - `award_child_bounty` - Close and pay out the specified amount for the completed work.
-//! - `claim_child_bounty` - Claim a specific child-bounty amount from the payout address.
+//! - `claim_child_bounty` - Claim a specific child bounty amount from the payout address.
-//! - `unassign_curator` - Unassign an accepted curator from a specific child-bounty.
+//! - `unassign_curator` - Unassign an accepted curator from a specific child bounty.
-//! - `close_child_bounty` - Cancel the child-bounty for a specific treasury amount and close the
+//! - `close_child_bounty` - Cancel the child bounty for a specific treasury amount and close the
 //!   bounty.
 
 // Most of the business logic in this pallet has been
 // originally contributed by "https://github.com/shamb0",
 // as part of the PR - https://github.com/paritytech/substrate/pull/7965.
 // The code has been moved here and then refactored in order to
-// extract child-bounties as a separate pallet.
+// extract child bounties as a separate pallet.
 
 #![cfg_attr(not(feature = "std"), no_std)]
 
@@ -101,7 +101,7 @@ pub struct ChildBounty<AccountId, Balance, BlockNumber> {
 pub enum ChildBountyStatus<AccountId, BlockNumber> {
 	/// The child-bounty is added and waiting for curator assignment.
 	Added,
-	/// A curator has been proposed by the parent-bounty curator. Waiting for
+	/// A curator has been proposed by the parent bounty curator. Waiting for
 	/// acceptance from the child-bounty curator.
 	CuratorProposed {
 		/// The assigned child-bounty curator of this bounty.
@@ -136,7 +136,7 @@ pub mod pallet {
 	pub trait Config:
 		frame_system::Config + pallet_treasury::Config + pallet_bounties::Config
 	{
-		/// Maximum number of child-bounties that can be added to a parent bounty.
+		/// Maximum number of child bounties that can be added to a parent bounty.
 		#[pallet::constant]
 		type MaxActiveChildBountyCount: Get<u32>;
 
@@ -157,7 +157,7 @@ pub mod pallet {
 		ParentBountyNotActive,
 		/// The bounty balance is not enough to add new child-bounty.
 		InsufficientBountyBalance,
-		/// Number of child-bounties exceeds limit `MaxActiveChildBountyCount`.
+		/// Number of child bounties exceeds limit `MaxActiveChildBountyCount`.
 		TooManyChildBounties,
 	}
 
@@ -184,14 +184,14 @@ pub mod pallet {
 	#[pallet::getter(fn child_bounty_count)]
 	pub type ChildBountyCount<T: Config> = StorageValue<_, BountyIndex, ValueQuery>;
 
-	/// Number of child-bounties per parent bounty.
+	/// Number of child bounties per parent bounty.
 	/// Map of parent bounty index to number of child bounties.
 	#[pallet::storage]
 	#[pallet::getter(fn parent_child_bounties)]
 	pub type ParentChildBounties<T: Config> =
 		StorageMap<_, Twox64Concat, BountyIndex, u32, ValueQuery>;
 
-	/// Child-bounties that have been added.
+	/// Child bounties that have been added.
 	#[pallet::storage]
 	#[pallet::getter(fn child_bounties)]
 	pub type ChildBounties<T: Config> = StorageDoubleMap<
@@ -226,7 +226,7 @@ pub mod pallet {
 		/// parent bounty to child-bounty account, if parent bounty has enough
 		/// funds, else the call fails.
 		///
-		/// Upper bound to maximum number of active  child-bounties that can be
+		/// Upper bound to maximum number of active  child bounties that can be
 		/// added are managed via runtime trait config
 		/// [`Config::MaxActiveChildBountyCount`].
 		///
@@ -427,12 +427,12 @@ pub mod pallet {
 		/// the curator of the parent bounty, or any signed origin.
 		///
 		/// For the origin other than T::RejectOrigin and the child-bounty
-		/// curator, parent-bounty must be in active state, for this call to
+		/// curator, parent bounty must be in active state, for this call to
 		/// work. We allow child-bounty curator and T::RejectOrigin to execute
-		/// this call irrespective of the parent-bounty state.
+		/// this call irrespective of the parent bounty state.
 		///
 		/// If this function is called by the `RejectOrigin` or the
-		/// parent-bounty curator, we assume that the child-bounty curator is
+		/// parent bounty curator, we assume that the child-bounty curator is
 		/// malicious or inactive. As a result, child-bounty curator deposit is
 		/// slashed.
 		///
@@ -486,7 +486,7 @@ pub mod pallet {
 						},
 						ChildBountyStatus::CuratorProposed { ref curator } => {
 							// A child-bounty curator has been proposed, but not accepted yet.
-							// Either `RejectOrigin`, parent-bounty curator or the proposed
+							// Either `RejectOrigin`, parent bounty curator or the proposed
 							// child-bounty curator can unassign the child-bounty curator.
 							ensure!(
 								maybe_sender.map_or(true, |sender| {
@@ -524,7 +524,7 @@ pub mod pallet {
 										update_due < frame_system::Pallet::<T>::block_number()
 									{
 										// Slash the child-bounty curator if
-										// + the call is made by the parent-bounty curator.
+										// + the call is made by the parent bounty curator.
 										// + or the curator is inactive.
 										slash_curator(curator, &mut child_bounty.curator_deposit);
 									// Continue to change bounty status below.
@@ -556,7 +556,7 @@ pub mod pallet {
 		///
 		/// The beneficiary will be able to claim the funds after a delay.
 		///
-		/// The dispatch origin for this call must be the master curator or
+		/// The dispatch origin for this call must be the parent curator or
 		/// curator of this child-bounty.
 		///
 		/// Parent bounty must be in active state, for this child-bounty call to
@@ -835,7 +835,7 @@ impl<T: Config> Pallet<T> {
 						// Nothing extra to do besides the removal of the child-bounty below.
 					},
 					ChildBountyStatus::Active { curator } => {
-						// Cancelled by master curator or RejectOrigin,
+						// Cancelled by parent curator or RejectOrigin,
 						// refund deposit of the working child-bounty curator.
 						let _ = T::Currency::unreserve(curator, child_bounty.curator_deposit);
 						// Then execute removal of the child-bounty below.
@@ -850,7 +850,7 @@ impl<T: Config> Pallet<T> {
 					},
 				}
 
-				// Revert the curator fee back to parent-bounty curator &
+				// Revert the curator fee back to parent bounty curator &
 				// reduce the active child-bounty count.
 				ChildrenCuratorFees::<T>::mutate(parent_bounty_id, |value| {
 					*value = value.saturating_sub(child_bounty.fee)
@@ -888,7 +888,7 @@ impl<T: Config> Pallet<T> {
 }
 
 // Implement ChildBountyManager to connect with the bounties pallet. This is
-// where we pass the active child-bounties and child curator fees to the parent
+// where we pass the active child bounties and child curator fees to the parent
 // bounty.
 impl<T: Config> pallet_bounties::ChildBountyManager<BalanceOf<T>> for Pallet<T> {
 	fn child_bounties_count(