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// This file is part of Substrate.
// Copyright (C) Parity Technologies (UK) Ltd.
// SPDX-License-Identifier: Apache-2.0
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//! # Tipping Pallet ( pallet-tips )
//!
//! > NOTE: This pallet is tightly coupled with pallet-treasury.
//!
//! A subsystem to allow for an agile "tipping" process, whereby a reward may be given without first
//! having a pre-determined stakeholder group come to consensus on how much should be paid.
//!
//! A group of `Tippers` is determined through the config `Config`. After half of these have
//! declared some amount that they believe a particular reported reason deserves, then a countdown
//! period is entered where any remaining members can declare their tip amounts also. After the
//! close of the countdown period, the median of all declared tips is paid to the reported
//! beneficiary, along with any finders fee, in case of a public (and bonded) original report.
//!
//!
//! ### Terminology
//!
//! Tipping protocol:
//! - **Tipping:** The process of gathering declarations of amounts to tip and taking the median
//! amount to be transferred from the treasury to a beneficiary account.
//! - **Tip Reason:** The reason for a tip; generally a URL which embodies or explains why a
//! particular individual (identified by an account ID) is worthy of a recognition by the
//! treasury.
//! - **Finder:** The original public reporter of some reason for tipping.
//! - **Finders Fee:** Some proportion of the tip amount that is paid to the reporter of the tip,
//! rather than the main beneficiary.
//!
//! ## Interface
//!
//! ### Dispatchable Functions
//!
//! Tipping protocol:
//! - `report_awesome` - Report something worthy of a tip and register for a finders fee.
//! - `retract_tip` - Retract a previous (finders fee registered) report.
//! - `tip_new` - Report an item worthy of a tip and declare a specific amount to tip.
//! - `tip` - Declare or redeclare an amount to tip for a particular reason.
//! - `close_tip` - Close and pay out a tip.
#![cfg_attr(not(feature = "std"), no_std)]
mod benchmarking;
mod tests;
pub mod migrations;
pub mod weights;
extern crate alloc;
use sp_runtime::{
traits::{AccountIdConversion, BadOrigin, Hash, StaticLookup, TrailingZeroInput, Zero},
Percent, RuntimeDebug,
};
use alloc::{vec, vec::Vec};
use codec::{Decode, Encode};
use frame_support::{
ensure,
traits::{
ContainsLengthBound, Currency, EnsureOrigin, ExistenceRequirement::KeepAlive, Get,
OnUnbalanced, ReservableCurrency, SortedMembers,
},
Parameter,
};
use frame_system::pallet_prelude::BlockNumberFor;
#[cfg(any(feature = "try-runtime", test))]
use sp_runtime::TryRuntimeError;
pub use pallet::*;
pub use weights::WeightInfo;
const LOG_TARGET: &str = "runtime::tips";
pub type BalanceOf<T, I = ()> = pallet_treasury::BalanceOf<T, I>;
pub type NegativeImbalanceOf<T, I = ()> = pallet_treasury::NegativeImbalanceOf<T, I>;
type AccountIdLookupOf<T> = <<T as frame_system::Config>::Lookup as StaticLookup>::Source;
/// An open tipping "motion". Retains all details of a tip including information on the finder
/// and the members who have voted.
#[derive(Clone, Eq, PartialEq, Encode, Decode, RuntimeDebug, scale_info::TypeInfo)]
pub struct OpenTip<
AccountId: Parameter,
Balance: Parameter,
BlockNumber: Parameter,
Hash: Parameter,
> {
/// The hash of the reason for the tip. The reason should be a human-readable UTF-8 encoded
/// string. A URL would be sensible.
reason: Hash,
/// The account to be tipped.
who: AccountId,
/// The account who began this tip.
finder: AccountId,
/// The amount held on deposit for this tip.
deposit: Balance,
/// The block number at which this tip will close if `Some`. If `None`, then no closing is
/// scheduled.
closes: Option<BlockNumber>,
/// The members who have voted for this tip. Sorted by AccountId.
tips: Vec<(AccountId, Balance)>,
/// Whether this tip should result in the finder taking a fee.
finders_fee: bool,
}
#[frame_support::pallet]
pub mod pallet {
use super::*;
use frame_support::pallet_prelude::*;
use frame_system::pallet_prelude::*;
/// The in-code storage version.
const STORAGE_VERSION: StorageVersion = StorageVersion::new(4);
#[pallet::pallet]
#[pallet::storage_version(STORAGE_VERSION)]
#[pallet::without_storage_info]
pub struct Pallet<T, I = ()>(_);
#[pallet::config]
pub trait Config<I: 'static = ()>: frame_system::Config + pallet_treasury::Config<I> {
/// The overarching event type.
type RuntimeEvent: From<Event<Self, I>>
+ IsType<<Self as frame_system::Config>::RuntimeEvent>;
/// Maximum acceptable reason length.
///
/// Benchmarks depend on this value, be sure to update weights file when changing this value
#[pallet::constant]
type MaximumReasonLength: Get<u32>;
/// The amount held on deposit per byte within the tip report reason or bounty description.
#[pallet::constant]
type DataDepositPerByte: Get<BalanceOf<Self, I>>;
/// The period for which a tip remains open after is has achieved threshold tippers.
#[pallet::constant]
type TipCountdown: Get<BlockNumberFor<Self>>;
/// The percent of the final tip which goes to the original reporter of the tip.
#[pallet::constant]
type TipFindersFee: Get<Percent>;
/// The non-zero amount held on deposit for placing a tip report.
#[pallet::constant]
type TipReportDepositBase: Get<BalanceOf<Self, I>>;
/// The maximum amount for a single tip.
#[pallet::constant]
type MaxTipAmount: Get<BalanceOf<Self, I>>;
/// Origin from which tippers must come.
///
/// `ContainsLengthBound::max_len` must be cost free (i.e. no storage read or heavy
/// operation). Benchmarks depend on the value of `ContainsLengthBound::max_len` be sure to
/// update weights file when altering this method.
type Tippers: SortedMembers<Self::AccountId> + ContainsLengthBound;
/// Handler for the unbalanced decrease when slashing for a removed tip.
type OnSlash: OnUnbalanced<NegativeImbalanceOf<Self, I>>;
/// Weight information for extrinsics in this pallet.
type WeightInfo: WeightInfo;
}
/// TipsMap that are not yet completed. Keyed by the hash of `(reason, who)` from the value.
/// This has the insecure enumerable hash function since the key itself is already
/// guaranteed to be a secure hash.
#[pallet::storage]
pub type Tips<T: Config<I>, I: 'static = ()> = StorageMap<
_,
Twox64Concat,
T::Hash,
OpenTip<T::AccountId, BalanceOf<T, I>, BlockNumberFor<T>, T::Hash>,
OptionQuery,
>;
/// Simple preimage lookup from the reason's hash to the original data. Again, has an
/// insecure enumerable hash since the key is guaranteed to be the result of a secure hash.
#[pallet::storage]
pub type Reasons<T: Config<I>, I: 'static = ()> =
StorageMap<_, Identity, T::Hash, Vec<u8>, OptionQuery>;
#[pallet::event]
#[pallet::generate_deposit(pub(super) fn deposit_event)]
pub enum Event<T: Config<I>, I: 'static = ()> {
/// A new tip suggestion has been opened.
NewTip { tip_hash: T::Hash },
/// A tip suggestion has reached threshold and is closing.
TipClosing { tip_hash: T::Hash },
/// A tip suggestion has been closed.
TipClosed { tip_hash: T::Hash, who: T::AccountId, payout: BalanceOf<T, I> },
/// A tip suggestion has been retracted.
TipRetracted { tip_hash: T::Hash },
/// A tip suggestion has been slashed.
TipSlashed { tip_hash: T::Hash, finder: T::AccountId, deposit: BalanceOf<T, I> },
}
#[pallet::error]
pub enum Error<T, I = ()> {
/// The reason given is just too big.
ReasonTooBig,
/// The tip was already found/started.
AlreadyKnown,
/// The tip hash is unknown.
UnknownTip,
/// The tip given was too generous.
MaxTipAmountExceeded,
/// The account attempting to retract the tip is not the finder of the tip.
NotFinder,
/// The tip cannot be claimed/closed because there are not enough tippers yet.
StillOpen,
/// The tip cannot be claimed/closed because it's still in the countdown period.
Premature,
}
#[pallet::call]
impl<T: Config<I>, I: 'static> Pallet<T, I> {
/// Report something `reason` that deserves a tip and claim any eventual the finder's fee.
///
/// The dispatch origin for this call must be _Signed_.
///
/// Payment: `TipReportDepositBase` will be reserved from the origin account, as well as
/// `DataDepositPerByte` for each byte in `reason`.
///
/// - `reason`: The reason for, or the thing that deserves, the tip; generally this will be
/// a UTF-8-encoded URL.
/// - `who`: The account which should be credited for the tip.
///
/// Emits `NewTip` if successful.
///
/// ## Complexity
/// - `O(R)` where `R` length of `reason`.
/// - encoding and hashing of 'reason'
#[pallet::call_index(0)]
#[pallet::weight(<T as Config<I>>::WeightInfo::report_awesome(reason.len() as u32))]
pub fn report_awesome(
origin: OriginFor<T>,
reason: Vec<u8>,
who: AccountIdLookupOf<T>,
) -> DispatchResult {
let finder = ensure_signed(origin)?;
let who = T::Lookup::lookup(who)?;
ensure!(
reason.len() <= T::MaximumReasonLength::get() as usize,
Error::<T, I>::ReasonTooBig
);
let reason_hash = T::Hashing::hash(&reason[..]);
ensure!(!Reasons::<T, I>::contains_key(&reason_hash), Error::<T, I>::AlreadyKnown);
let hash = T::Hashing::hash_of(&(&reason_hash, &who));
ensure!(!Tips::<T, I>::contains_key(&hash), Error::<T, I>::AlreadyKnown);
let deposit = T::TipReportDepositBase::get() +
T::DataDepositPerByte::get() * (reason.len() as u32).into();
T::Currency::reserve(&finder, deposit)?;
Reasons::<T, I>::insert(&reason_hash, &reason);
let tip = OpenTip {
reason: reason_hash,
who,
finder,
deposit,
closes: None,
tips: vec![],
finders_fee: true,
};
Tips::<T, I>::insert(&hash, tip);
Self::deposit_event(Event::NewTip { tip_hash: hash });
Ok(())
}
/// Retract a prior tip-report from `report_awesome`, and cancel the process of tipping.
///
/// If successful, the original deposit will be unreserved.
///
/// The dispatch origin for this call must be _Signed_ and the tip identified by `hash`
/// must have been reported by the signing account through `report_awesome` (and not
/// through `tip_new`).
///
/// - `hash`: The identity of the open tip for which a tip value is declared. This is formed
/// as the hash of the tuple of the original tip `reason` and the beneficiary account ID.
///
/// Emits `TipRetracted` if successful.
///
/// ## Complexity
/// - `O(1)`
/// - Depends on the length of `T::Hash` which is fixed.
#[pallet::call_index(1)]
#[pallet::weight(<T as Config<I>>::WeightInfo::retract_tip())]
pub fn retract_tip(origin: OriginFor<T>, hash: T::Hash) -> DispatchResult {
let who = ensure_signed(origin)?;
let tip = Tips::<T, I>::get(&hash).ok_or(Error::<T, I>::UnknownTip)?;
ensure!(tip.finder == who, Error::<T, I>::NotFinder);
Reasons::<T, I>::remove(&tip.reason);
Tips::<T, I>::remove(&hash);
if !tip.deposit.is_zero() {
let err_amount = T::Currency::unreserve(&who, tip.deposit);
debug_assert!(err_amount.is_zero());
}
Self::deposit_event(Event::TipRetracted { tip_hash: hash });
Ok(())
}
/// Give a tip for something new; no finder's fee will be taken.
///
/// The dispatch origin for this call must be _Signed_ and the signing account must be a
/// member of the `Tippers` set.
///
/// - `reason`: The reason for, or the thing that deserves, the tip; generally this will be
/// a UTF-8-encoded URL.
/// - `who`: The account which should be credited for the tip.
/// - `tip_value`: The amount of tip that the sender would like to give. The median tip
/// value of active tippers will be given to the `who`.
///
/// Emits `NewTip` if successful.
///
/// ## Complexity
/// - `O(R + T)` where `R` length of `reason`, `T` is the number of tippers.
/// - `O(T)`: decoding `Tipper` vec of length `T`. `T` is charged as upper bound given by
/// `ContainsLengthBound`. The actual cost depends on the implementation of
/// `T::Tippers`.
/// - `O(R)`: hashing and encoding of reason of length `R`
#[pallet::call_index(2)]
#[pallet::weight(<T as Config<I>>::WeightInfo::tip_new(reason.len() as u32, T::Tippers::max_len() as u32))]
pub fn tip_new(
origin: OriginFor<T>,
reason: Vec<u8>,
who: AccountIdLookupOf<T>,
#[pallet::compact] tip_value: BalanceOf<T, I>,
) -> DispatchResult {
let tipper = ensure_signed(origin)?;
let who = T::Lookup::lookup(who)?;
ensure!(T::Tippers::contains(&tipper), BadOrigin);
ensure!(T::MaxTipAmount::get() >= tip_value, Error::<T, I>::MaxTipAmountExceeded);
let reason_hash = T::Hashing::hash(&reason[..]);
ensure!(!Reasons::<T, I>::contains_key(&reason_hash), Error::<T, I>::AlreadyKnown);
let hash = T::Hashing::hash_of(&(&reason_hash, &who));
Reasons::<T, I>::insert(&reason_hash, &reason);
Self::deposit_event(Event::NewTip { tip_hash: hash });
let tips = vec![(tipper.clone(), tip_value)];
let tip = OpenTip {
reason: reason_hash,
who,
finder: tipper,
deposit: Zero::zero(),
closes: None,
tips,
finders_fee: false,
};
Tips::<T, I>::insert(&hash, tip);
Ok(())
}
/// Declare a tip value for an already-open tip.
///
/// The dispatch origin for this call must be _Signed_ and the signing account must be a
/// member of the `Tippers` set.
///
/// - `hash`: The identity of the open tip for which a tip value is declared. This is formed
/// as the hash of the tuple of the hash of the original tip `reason` and the beneficiary
/// account ID.
/// - `tip_value`: The amount of tip that the sender would like to give. The median tip
/// value of active tippers will be given to the `who`.
///
/// Emits `TipClosing` if the threshold of tippers has been reached and the countdown period
/// has started.
///
/// ## Complexity
/// - `O(T)` where `T` is the number of tippers. decoding `Tipper` vec of length `T`, insert
/// tip and check closing, `T` is charged as upper bound given by `ContainsLengthBound`.
/// The actual cost depends on the implementation of `T::Tippers`.
///
/// Actually weight could be lower as it depends on how many tips are in `OpenTip` but it
/// is weighted as if almost full i.e of length `T-1`.
#[pallet::call_index(3)]
#[pallet::weight(<T as Config<I>>::WeightInfo::tip(T::Tippers::max_len() as u32))]
pub fn tip(
origin: OriginFor<T>,
hash: T::Hash,
#[pallet::compact] tip_value: BalanceOf<T, I>,
) -> DispatchResult {
let tipper = ensure_signed(origin)?;
ensure!(T::Tippers::contains(&tipper), BadOrigin);
ensure!(T::MaxTipAmount::get() >= tip_value, Error::<T, I>::MaxTipAmountExceeded);
let mut tip = Tips::<T, I>::get(hash).ok_or(Error::<T, I>::UnknownTip)?;
if Self::insert_tip_and_check_closing(&mut tip, tipper, tip_value) {
Self::deposit_event(Event::TipClosing { tip_hash: hash });
}
Tips::<T, I>::insert(&hash, tip);
Ok(())
}
/// Close and payout a tip.
///
/// The dispatch origin for this call must be _Signed_.
///
/// The tip identified by `hash` must have finished its countdown period.
///
/// - `hash`: The identity of the open tip for which a tip value is declared. This is formed
/// as the hash of the tuple of the original tip `reason` and the beneficiary account ID.
///
/// ## Complexity
/// - : `O(T)` where `T` is the number of tippers. decoding `Tipper` vec of length `T`. `T`
/// is charged as upper bound given by `ContainsLengthBound`. The actual cost depends on
/// the implementation of `T::Tippers`.
#[pallet::call_index(4)]
#[pallet::weight(<T as Config<I>>::WeightInfo::close_tip(T::Tippers::max_len() as u32))]
pub fn close_tip(origin: OriginFor<T>, hash: T::Hash) -> DispatchResult {
ensure_signed(origin)?;
let tip = Tips::<T, I>::get(hash).ok_or(Error::<T, I>::UnknownTip)?;
let n = tip.closes.as_ref().ok_or(Error::<T, I>::StillOpen)?;
ensure!(frame_system::Pallet::<T>::block_number() >= *n, Error::<T, I>::Premature);
// closed.
Reasons::<T, I>::remove(&tip.reason);
Tips::<T, I>::remove(hash);
Self::payout_tip(hash, tip);
Ok(())
}
/// Remove and slash an already-open tip.
///
/// May only be called from `T::RejectOrigin`.
///
/// As a result, the finder is slashed and the deposits are lost.
///
/// Emits `TipSlashed` if successful.
///
/// ## Complexity
/// - O(1).
#[pallet::call_index(5)]
#[pallet::weight(<T as Config<I>>::WeightInfo::slash_tip(T::Tippers::max_len() as u32))]
pub fn slash_tip(origin: OriginFor<T>, hash: T::Hash) -> DispatchResult {
T::RejectOrigin::ensure_origin(origin)?;
let tip = Tips::<T, I>::take(hash).ok_or(Error::<T, I>::UnknownTip)?;
if !tip.deposit.is_zero() {
let imbalance = T::Currency::slash_reserved(&tip.finder, tip.deposit).0;
T::OnSlash::on_unbalanced(imbalance);
}
Reasons::<T, I>::remove(&tip.reason);
Self::deposit_event(Event::TipSlashed {
tip_hash: hash,
finder: tip.finder,
deposit: tip.deposit,
});
Ok(())
}
}
#[pallet::hooks]
impl<T: Config<I>, I: 'static> Hooks<BlockNumberFor<T>> for Pallet<T, I> {
fn integrity_test() {
assert!(
!T::TipReportDepositBase::get().is_zero(),
"`TipReportDepositBase` should not be zero",
);
}
#[cfg(feature = "try-runtime")]
fn try_state(_n: BlockNumberFor<T>) -> Result<(), TryRuntimeError> {
Self::do_try_state()
}
}
}
impl<T: Config<I>, I: 'static> Pallet<T, I> {
// Add public immutables and private mutables.
/// Access tips storage from outside
pub fn tips(
hash: T::Hash,
) -> Option<OpenTip<T::AccountId, BalanceOf<T, I>, BlockNumberFor<T>, T::Hash>> {
Tips::<T, I>::get(hash)
}
/// Access reasons storage from outside
pub fn reasons(hash: T::Hash) -> Option<Vec<u8>> {
Reasons::<T, I>::get(hash)
}
/// The account ID of the treasury pot.
///
/// This actually does computation. If you need to keep using it, then make sure you cache the
/// value and only call this once.
pub fn account_id() -> T::AccountId {
T::PalletId::get().into_account_truncating()
}
/// Given a mutable reference to an `OpenTip`, insert the tip into it and check whether it
/// closes, if so, then deposit the relevant event and set closing accordingly.
///
/// `O(T)` and one storage access.
fn insert_tip_and_check_closing(
tip: &mut OpenTip<T::AccountId, BalanceOf<T, I>, BlockNumberFor<T>, T::Hash>,
tipper: T::AccountId,
tip_value: BalanceOf<T, I>,
) -> bool {
match tip.tips.binary_search_by_key(&&tipper, |x| &x.0) {
Ok(pos) => tip.tips[pos] = (tipper, tip_value),
Err(pos) => tip.tips.insert(pos, (tipper, tip_value)),
}
Self::retain_active_tips(&mut tip.tips);
let threshold = (T::Tippers::count() + 1) / 2;
if tip.tips.len() >= threshold && tip.closes.is_none() {
tip.closes = Some(frame_system::Pallet::<T>::block_number() + T::TipCountdown::get());
true
} else {
false
}
}
/// Remove any non-members of `Tippers` from a `tips` vector. `O(T)`.
fn retain_active_tips(tips: &mut Vec<(T::AccountId, BalanceOf<T, I>)>) {
let members = T::Tippers::sorted_members();
let mut members_iter = members.iter();
let mut member = members_iter.next();
tips.retain(|(ref a, _)| loop {
match member {
None => break false,
Some(m) if m > a => break false,
Some(m) => {
member = members_iter.next();
if m < a {
continue
} else {
break true
}
},
}
});
}
/// Execute the payout of a tip.
///
/// Up to three balance operations.
/// Plus `O(T)` (`T` is Tippers length).
fn payout_tip(
hash: T::Hash,
tip: OpenTip<T::AccountId, BalanceOf<T, I>, BlockNumberFor<T>, T::Hash>,
) {
let mut tips = tip.tips;
Self::retain_active_tips(&mut tips);
tips.sort_by_key(|i| i.1);
let treasury = Self::account_id();
let max_payout = pallet_treasury::Pallet::<T, I>::pot();
let mut payout = tips[tips.len() / 2].1.min(max_payout);
if !tip.deposit.is_zero() {
let err_amount = T::Currency::unreserve(&tip.finder, tip.deposit);
debug_assert!(err_amount.is_zero());
}
if tip.finders_fee && tip.finder != tip.who {
// pay out the finder's fee.
let finders_fee = T::TipFindersFee::get() * payout;
payout -= finders_fee;
// this should go through given we checked it's at most the free balance, but still
// we only make a best-effort.
let res = T::Currency::transfer(&treasury, &tip.finder, finders_fee, KeepAlive);
debug_assert!(res.is_ok());
}
// same as above: best-effort only.
let res = T::Currency::transfer(&treasury, &tip.who, payout, KeepAlive);
debug_assert!(res.is_ok());
Self::deposit_event(Event::TipClosed { tip_hash: hash, who: tip.who, payout });
}
pub fn migrate_retract_tip_for_tip_new(module: &[u8], item: &[u8]) {
/// An open tipping "motion". Retains all details of a tip including information on the
/// finder and the members who have voted.
#[derive(Clone, Eq, PartialEq, Encode, Decode, RuntimeDebug)]
pub struct OldOpenTip<
AccountId: Parameter,
Balance: Parameter,
BlockNumber: Parameter,
Hash: Parameter,
> {
/// The hash of the reason for the tip. The reason should be a human-readable UTF-8
/// encoded string. A URL would be sensible.
reason: Hash,
/// The account to be tipped.
who: AccountId,
/// The account who began this tip and the amount held on deposit.
finder: Option<(AccountId, Balance)>,
/// The block number at which this tip will close if `Some`. If `None`, then no closing
/// is scheduled.
closes: Option<BlockNumber>,
/// The members who have voted for this tip. Sorted by AccountId.
tips: Vec<(AccountId, Balance)>,
}
use frame_support::{migration::storage_key_iter, Twox64Concat};
let zero_account = T::AccountId::decode(&mut TrailingZeroInput::new(&[][..]))
.expect("infinite input; qed");
for (hash, old_tip) in storage_key_iter::<
T::Hash,
OldOpenTip<T::AccountId, BalanceOf<T, I>, BlockNumberFor<T>, T::Hash>,
Twox64Concat,
>(module, item)
.drain()
{
let (finder, deposit, finders_fee) = match old_tip.finder {
Some((finder, deposit)) => (finder, deposit, true),
None => (zero_account.clone(), Zero::zero(), false),
};
let new_tip = OpenTip {
reason: old_tip.reason,
who: old_tip.who,
finder,
deposit,
closes: old_tip.closes,
tips: old_tip.tips,
finders_fee,
};
Tips::<T, I>::insert(hash, new_tip)
}
}
/// Ensure the correctness of the state of this pallet.
///
/// This should be valid before and after each state transition of this pallet.
///
/// ## Invariants:
/// 1. The number of entries in `Tips` should be equal to `Reasons`.
/// 2. Reasons exists for each Tip[`OpenTip.reason`].
/// 3. If `OpenTip.finders_fee` is true, then OpenTip.deposit should be greater than zero.
#[cfg(any(feature = "try-runtime", test))]
pub fn do_try_state() -> Result<(), TryRuntimeError> {
let reasons = Reasons::<T, I>::iter_keys().collect::<Vec<_>>();
let tips = Tips::<T, I>::iter_keys().collect::<Vec<_>>();
ensure!(
reasons.len() == tips.len(),
TryRuntimeError::Other("Equal length of entries in `Tips` and `Reasons` Storage")
);
for tip in Tips::<T, I>::iter_keys() {
let open_tip = Tips::<T, I>::get(&tip).expect("All map keys are valid; qed");
if open_tip.finders_fee {
ensure!(
!open_tip.deposit.is_zero(),
TryRuntimeError::Other(
"Tips with `finders_fee` should have non-zero `deposit`."
)
)
}
ensure!(
reasons.contains(&open_tip.reason),
TryRuntimeError::Other("no reason for this tip")
);
}
Ok(())
}
}