Struct pallet_balances::pallet::Pallet

pub struct Pallet<T, I = ()>(_);

The pallet implementing the on-chain logic.

Implementations

impl<T: Config<I>, I: 'static> Pallet<T, I>

pub fn transfer(
    origin: OriginFor<T>,
    dest: <T::Lookup as StaticLookup>::Source,
    value: T::Balance
) -> DispatchResultWithPostInfo

Transfer some liquid free balance to another account.

transfer will set the FreeBalance of the sender and receiver. It will decrease the total issuance of the system by the TransferFee. If the sender’s account is below the existential deposit as a result of the transfer, the account will be reaped.

The dispatch origin for this call must be Signed by the transactor.

• Dependent on arguments but not critical, given proper implementations for input config types. See related functions below.
• It contains a limited number of reads and writes internally and no complex computation.

Related functions:

• ensure_can_withdraw is always called internally but has a bounded complexity.
• Transferring balances to accounts that did not exist before will cause T::OnNewAccount::on_new_account to be called.
• Removing enough funds from an account will trigger T::DustRemoval::on_unbalanced.
• transfer_keep_alive works the same way as transfer, but has an additional check that the transfer will not kill the origin account.

---

• Base Weight: 73.64 µs, worst case scenario (account created, account removed)
• DB Weight: 1 Read and 1 Write to destination account
• Origin account is already in memory, so no DB operations for them.

pub fn set_balance(
    origin: OriginFor<T>,
    who: <T::Lookup as StaticLookup>::Source,
    new_free: T::Balance,
    new_reserved: T::Balance
) -> DispatchResultWithPostInfo

Set the balances of a given account.

This will alter FreeBalance and ReservedBalance in storage. it will also decrease the total issuance of the system (TotalIssuance). If the new free or reserved balance is below the existential deposit, it will reset the account nonce (frame_system::AccountNonce).

The dispatch origin for this call is root.

• Independent of the arguments.
• Contains a limited number of reads and writes.

---

• Base Weight:
  • Creating: 27.56 µs
  • Killing: 35.11 µs
• DB Weight: 1 Read, 1 Write to who

pub fn force_transfer(
    origin: OriginFor<T>,
    source: <T::Lookup as StaticLookup>::Source,
    dest: <T::Lookup as StaticLookup>::Source,
    value: T::Balance
) -> DispatchResultWithPostInfo

Exactly as transfer, except the origin must be root and the source account may be specified.

• Same as transfer, but additional read and write because the source account is not assumed to be in the overlay.

pub fn transfer_keep_alive(
    origin: OriginFor<T>,
    dest: <T::Lookup as StaticLookup>::Source,
    value: T::Balance
) -> DispatchResultWithPostInfo

Same as the transfer call, but with a check that the transfer will not kill the origin account.

99% of the time you want transfer instead.

• Cheaper than transfer because account cannot be killed.
• Base Weight: 51.4 µs
• DB Weight: 1 Read and 1 Write to dest (sender is in overlay already) #

pub fn transfer_all(
    origin: OriginFor<T>,
    dest: <T::Lookup as StaticLookup>::Source,
    keep_alive: bool
) -> DispatchResultWithPostInfo

Transfer the entire transferable balance from the caller account.

NOTE: This function only attempts to transfer transferable balances. This means that any locked, reserved, or existential deposits (when keep_alive is true), will not be transferred by this function. To ensure that this function results in a killed account, you might need to prepare the account by removing any reference counters, storage deposits, etc…

The dispatch origin of this call must be Signed.

• dest: The recipient of the transfer.
• keep_alive: A boolean to determine if the transfer_all operation should send all of the funds the account has, causing the sender account to be killed (false), or transfer everything except at least the existential deposit, which will guarantee to keep the sender account alive (true). #
• O(1). Just like transfer, but reading the user’s transferable balance first. #

impl<T: Config<I>, I: 'static> Pallet<T, I>

pub fn total_issuance() -> T::Balance

The total units issued in the system.

impl<T: Config<I>, I: 'static> Pallet<T, I>

pub fn locks<KArg>(
    k: KArg
) -> WeakBoundedVec<BalanceLock<T::Balance>, T::MaxLocks> where
    KArg: EncodeLike<T::AccountId>, 

Any liquidity locks on some account balances. NOTE: Should only be accessed when setting, changing and freeing a lock.

impl<T: Config<I>, I: 'static> Pallet<T, I>

pub fn reserves<KArg>(
    k: KArg
) -> BoundedVec<ReserveData<T::ReserveIdentifier, T::Balance>, T::MaxReserves> where
    KArg: EncodeLike<T::AccountId>, 

Named reserves on some account balances.

impl<T: Config<I>, I: 'static> Pallet<T, I>

pub fn free_balance(who: impl Borrow<T::AccountId>) -> T::Balance

Get the free balance of an account.

pub fn usable_balance(who: impl Borrow<T::AccountId>) -> T::Balance

Get the balance of an account that can be used for transfers, reservations, or any other non-locking, non-transaction-fee activity. Will be at most free_balance.

pub fn usable_balance_for_fees(who: impl Borrow<T::AccountId>) -> T::Balance

Get the balance of an account that can be used for paying transaction fees (not tipping, or any other kind of fees, though). Will be at most free_balance.

pub fn reserved_balance(who: impl Borrow<T::AccountId>) -> T::Balance

Get the reserved balance of an account.

pub fn mutate_account<R>(
    who: &T::AccountId,
    f: impl FnOnce(&mut AccountData<T::Balance>) -> R
) -> Result<R, DispatchError>

Mutate an account to some new value, or delete it entirely with None. Will enforce ExistentialDeposit law, annulling the account as needed.

NOTE: Doesn’t do any preparatory work for creating a new account, so should only be used when it is known that the account already exists.

NOTE: LOW-LEVEL: This will not attempt to maintain total issuance. It is expected that the caller will do this.

Trait Implementations

impl<T: Config<I>, I: 'static> Benchmarking<BenchmarkResults> for Pallet<T, I> where
    T: Config, 

fn benchmarks(extra: bool) -> Vec<BenchmarkMetadata>

Get the benchmarks available for this pallet. Generally there is one benchmark per extrinsic, so these are sometimes just called “extrinsics”.

fn run_benchmark(
    extrinsic: &[u8],
    c: &[(BenchmarkParameter, u32)],
    whitelist: &[TrackedStorageKey],
    verify: bool,
    internal_repeats: u32
) -> Result<Vec<BenchmarkResults>, &'static str>

Run the benchmarks for this pallet.

impl<T: Config<I>, I: 'static> Callable<T> for Pallet<T, I>

type Call = Call<T, I>

impl<T, I> Clone for Pallet<T, I>

fn clone(&self) -> Self

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl<T: Config<I>, I: 'static> Currency<<T as Config>::AccountId> for Pallet<T, I> where
    T::Balance: MaybeSerializeDeserialize + Debug, 

fn slash(
    who: &T::AccountId,
    value: Self::Balance
) -> (Self::NegativeImbalance, Self::Balance)

Slash a target account who, returning the negative imbalance created and any left over amount that could not be slashed.

Is a no-op if value to be slashed is zero or the account does not exist.

NOTE: slash() prefers free balance, but assumes that reserve balance can be drawn from in extreme circumstances. can_slash() should be used prior to slash() to avoid having to draw from reserved funds, however we err on the side of punishment if things are inconsistent or can_slash wasn’t used appropriately.

fn deposit_into_existing(
    who: &T::AccountId,
    value: Self::Balance
) -> Result<Self::PositiveImbalance, DispatchError>

Deposit some value into the free balance of an existing target account who.

Is a no-op if the value to be deposited is zero.

fn deposit_creating(
    who: &T::AccountId,
    value: Self::Balance
) -> Self::PositiveImbalance

Deposit some value into the free balance of who, possibly creating a new account.

This function is a no-op if:

• the value to be deposited is zero; or
• the value to be deposited is less than the required ED and the account does not yet exist; or
• the deposit would necessitate the account to exist and there are no provider references; or
• value is so large it would cause the balance of who to overflow.

fn withdraw(
    who: &T::AccountId,
    value: Self::Balance,
    reasons: WithdrawReasons,
    liveness: ExistenceRequirement
) -> Result<Self::NegativeImbalance, DispatchError>

Withdraw some free balance from an account, respecting existence requirements.

Is a no-op if value to be withdrawn is zero.

fn make_free_balance_be(
    who: &T::AccountId,
    value: Self::Balance
) -> SignedImbalance<Self::Balance, Self::PositiveImbalance>

Force the new free balance of a target account who to some new value balance.

type Balance = T::Balance

The balance of an account.

type PositiveImbalance = PositiveImbalance<T, I>

The opaque token type for an imbalance. This is returned by unbalanced operations and must be dealt with. It may be dropped but cannot be cloned.

type NegativeImbalance = NegativeImbalance<T, I>

The opaque token type for an imbalance. This is returned by unbalanced operations and must be dealt with. It may be dropped but cannot be cloned.

fn total_balance(who: &T::AccountId) -> Self::Balance

The combined balance of who.

fn can_slash(who: &T::AccountId, value: Self::Balance) -> bool

Same result as slash(who, value) (but without the side-effects) assuming there are no balance changes in the meantime and only the reserved balance is not taken into account.

fn total_issuance() -> Self::Balance

The total amount of issuance in the system.

fn minimum_balance() -> Self::Balance

The minimum balance any single account may have. This is equivalent to the Balances module’s ExistentialDeposit.

fn burn(amount: Self::Balance) -> Self::PositiveImbalance

Reduce the total issuance by amount and return the according imbalance. The imbalance will typically be used to reduce an account by the same amount with e.g. settle.

fn issue(amount: Self::Balance) -> Self::NegativeImbalance

Increase the total issuance by amount and return the according imbalance. The imbalance will typically be used to increase an account by the same amount with e.g. resolve_into_existing or resolve_creating.

fn free_balance(who: &T::AccountId) -> Self::Balance

The ‘free’ balance of a given account.

fn ensure_can_withdraw(
    who: &T::AccountId,
    amount: T::Balance,
    reasons: WithdrawReasons,
    new_balance: T::Balance
) -> DispatchResult

Returns Ok iff the account is able to make a withdrawal of the given amount for the given reason. Basically, it’s just a dry-run of withdraw.

fn transfer(
    transactor: &T::AccountId,
    dest: &T::AccountId,
    value: Self::Balance,
    existence_requirement: ExistenceRequirement
) -> DispatchResult

Transfer some liquid free balance to another staker.

fn pair(
    amount: Self::Balance
) -> (Self::PositiveImbalance, Self::NegativeImbalance)

Produce a pair of imbalances that cancel each other out exactly.

fn resolve_into_existing(
    who: &AccountId,
    value: Self::NegativeImbalance
) -> Result<(), Self::NegativeImbalance>

Similar to deposit_creating, only accepts a NegativeImbalance and returns nothing on success.

fn resolve_creating(who: &AccountId, value: Self::NegativeImbalance)

Similar to deposit_creating, only accepts a NegativeImbalance and returns nothing on success.

fn settle(
    who: &AccountId,
    value: Self::PositiveImbalance,
    reasons: WithdrawReasons,
    liveness: ExistenceRequirement
) -> Result<(), Self::PositiveImbalance>

Similar to withdraw, only accepts a PositiveImbalance and returns nothing on success.

impl<T, I> Debug for Pallet<T, I>

fn fmt(&self, fmt: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl<T: Config<I>, I: 'static> GetStorageVersion for Pallet<T, I>

fn current_storage_version() -> StorageVersion

Returns the current storage version as supported by the pallet.

fn on_chain_storage_version() -> StorageVersion

Returns the on-chain storage version of the pallet as stored in the storage.

impl<T: Config<I>, I: 'static> Hooks<<T as Config>::BlockNumber> for Pallet<T, I>

fn on_finalize(_n: BlockNumber)

The block is being finalized. Implement to have something happen.

fn on_idle(_n: BlockNumber, _remaining_weight: u64) -> u64

This will be run when the block is being finalized (before on_finalize). Implement to have something happen using the remaining weight. Will not fire if the remaining weight is 0. Return the weight used, the hook will subtract it from current weight used and pass the result to the next on_idle hook if it exists.

fn on_initialize(_n: BlockNumber) -> u64

The block is being initialized. Implement to have something happen.

fn on_runtime_upgrade() -> u64

Perform a module upgrade.

fn pre_upgrade() -> Result<(), &'static str>

Execute some pre-checks prior to a runtime upgrade.

fn post_upgrade() -> Result<(), &'static str>

Execute some post-checks after a runtime upgrade.

fn offchain_worker(_n: BlockNumber)

Implementing this function on a module allows you to perform long-running tasks that make (by default) validators generate transactions that feed results of those long-running computations back on chain.

fn integrity_test()

Run integrity test.

impl<T: Config<I>, I: 'static> Inspect<<T as Config>::AccountId> for Pallet<T, I>

type Balance = T::Balance

Scalar type for representing balance of an account.

fn total_issuance() -> Self::Balance

The total amount of issuance in the system.

fn minimum_balance() -> Self::Balance

The minimum balance any single account may have.

fn balance(who: &T::AccountId) -> Self::Balance

Get the balance of who.

fn reducible_balance(who: &T::AccountId, keep_alive: bool) -> Self::Balance

Get the maximum amount that who can withdraw/transfer successfully.

fn can_deposit(who: &T::AccountId, amount: Self::Balance) -> DepositConsequence

Returns true if the balance of who may be increased by amount.

fn can_withdraw(
    who: &T::AccountId,
    amount: Self::Balance
) -> WithdrawConsequence<Self::Balance>

Returns Failed if the balance of who may not be decreased by amount, otherwise the consequence.

impl<T: Config<I>, I: 'static> InspectHold<<T as Config>::AccountId> for Pallet<T, I>

fn balance_on_hold(who: &T::AccountId) -> T::Balance

Amount of funds held in reserve by who.

fn can_hold(who: &T::AccountId, amount: T::Balance) -> bool

Check to see if some amount of funds of who may be placed on hold.

impl<T: Config<I>, I: 'static> IntegrityTest for Pallet<T, I>

fn integrity_test()

Run integrity test.

impl<T: Config<I>, I: 'static> LockableCurrency<<T as Config>::AccountId> for Pallet<T, I> where
    T::Balance: MaybeSerializeDeserialize + Debug, 

type Moment = T::BlockNumber

The quantity used to denote time; usually just a BlockNumber.

type MaxLocks = T::MaxLocks

The maximum number of locks a user should have on their account.

fn set_lock(
    id: LockIdentifier,
    who: &T::AccountId,
    amount: T::Balance,
    reasons: WithdrawReasons
)

Create a new balance lock on account who.

fn extend_lock(
    id: LockIdentifier,
    who: &T::AccountId,
    amount: T::Balance,
    reasons: WithdrawReasons
)

Changes a balance lock (selected by id) so that it becomes less liquid in all parameters or creates a new one if it does not exist.

fn remove_lock(id: LockIdentifier, who: &T::AccountId)

Remove an existing lock.

impl<T: Config<I>, I: 'static> ModuleErrorMetadata for Pallet<T, I>

fn metadata() -> &'static [ErrorMetadata]

impl<T: Config<I>, I: 'static> Mutate<<T as Config>::AccountId> for Pallet<T, I>

fn mint_into(who: &T::AccountId, amount: Self::Balance) -> DispatchResult

Increase the balance of who by exactly amount, minting new tokens. If that isn’t possible then an Err is returned and nothing is changed.

fn burn_from(
    who: &T::AccountId,
    amount: Self::Balance
) -> Result<Self::Balance, DispatchError>

Decrease the balance of who by at least amount, possibly slightly more in the case of minimum_balance requirements, burning the tokens. If that isn’t possible then an Err is returned and nothing is changed. If successful, the amount of tokens reduced is returned.

fn slash(
    who: &AccountId,
    amount: Self::Balance
) -> Result<Self::Balance, DispatchError>

Attempt to reduce the balance of who by as much as possible up to amount, and possibly slightly more due to minimum_balance requirements. If no decrease is possible then an Err is returned and nothing is changed. If successful, the amount of tokens reduced is returned.

fn teleport(
    source: &AccountId,
    dest: &AccountId,
    amount: Self::Balance
) -> Result<Self::Balance, DispatchError>

Transfer funds from one account into another. The default implementation uses mint_into and burn_from and may generate unwanted events.

impl<T: Config<I>, I: 'static> MutateHold<<T as Config>::AccountId> for Pallet<T, I>

fn hold(who: &T::AccountId, amount: Self::Balance) -> DispatchResult

Hold some funds in an account.

fn release(
    who: &T::AccountId,
    amount: Self::Balance,
    best_effort: bool
) -> Result<T::Balance, DispatchError>

Release up to amount held funds in an account.

fn transfer_held(
    source: &T::AccountId,
    dest: &T::AccountId,
    amount: Self::Balance,
    best_effort: bool,
    on_hold: bool
) -> Result<Self::Balance, DispatchError>

Transfer held funds into a destination account.

impl<T: Config<I>, I: 'static> NamedReservableCurrency<<T as Config>::AccountId> for Pallet<T, I> where
    T::Balance: MaybeSerializeDeserialize + Debug, 

fn reserve_named(
    id: &Self::ReserveIdentifier,
    who: &T::AccountId,
    value: Self::Balance
) -> DispatchResult

Move value from the free balance from who to a named reserve balance.

Is a no-op if value to be reserved is zero.

fn unreserve_named(
    id: &Self::ReserveIdentifier,
    who: &T::AccountId,
    value: Self::Balance
) -> Self::Balance

Unreserve some funds, returning any amount that was unable to be unreserved.

Is a no-op if the value to be unreserved is zero.

fn slash_reserved_named(
    id: &Self::ReserveIdentifier,
    who: &T::AccountId,
    value: Self::Balance
) -> (Self::NegativeImbalance, Self::Balance)

Slash from reserved balance, returning the negative imbalance created, and any amount that was unable to be slashed.

Is a no-op if the value to be slashed is zero.

fn repatriate_reserved_named(
    id: &Self::ReserveIdentifier,
    slashed: &T::AccountId,
    beneficiary: &T::AccountId,
    value: Self::Balance,
    status: Status
) -> Result<Self::Balance, DispatchError>

Move the reserved balance of one account into the balance of another, according to status. If status is Reserved, the balance will be reserved with given id.

Is a no-op if:

• the value to be moved is zero; or
• the slashed id equal to beneficiary and the status is Reserved.

type ReserveIdentifier = T::ReserveIdentifier

An identifier for a reserve. Used for disambiguating different reserves so that they can be individually replaced or removed.

fn reserved_balance_named(
    id: &Self::ReserveIdentifier,
    who: &T::AccountId
) -> Self::Balance

The amount of the balance of a given account that is externally reserved; this can still get slashed, but gets slashed last of all.

fn ensure_reserved_named(
    id: &Self::ReserveIdentifier,
    who: &AccountId,
    value: Self::Balance
) -> Result<(), DispatchError>

Ensure the reserved balance is equal to value.

fn unreserve_all_named(
    id: &Self::ReserveIdentifier,
    who: &AccountId
) -> Self::Balance

Unreserve all the named reserved balances, returning unreserved amount.

fn slash_all_reserved_named(
    id: &Self::ReserveIdentifier,
    who: &AccountId
) -> Self::NegativeImbalance

Slash all the reserved balance, returning the negative imbalance created.

fn repatriate_all_reserved_named(
    id: &Self::ReserveIdentifier,
    slashed: &AccountId,
    beneficiary: &AccountId,
    status: BalanceStatus
) -> Result<(), DispatchError>

Move all the named reserved balance of one account into the balance of another, according to status. If status is Reserved, the balance will be reserved with given id.

impl<T: Config<I>, I: 'static> OffchainWorker<<T as Config>::BlockNumber> for Pallet<T, I>

fn offchain_worker(n: <T as Config>::BlockNumber)

This function is being called after every block import (when fully synced).

impl<T: Config<I>, I: 'static> OnFinalize<<T as Config>::BlockNumber> for Pallet<T, I>

fn on_finalize(n: <T as Config>::BlockNumber)

The block is being finalized. Implement to have something happen.

impl<T: Config<I>, I: 'static> OnGenesis for Pallet<T, I>

fn on_genesis()

Something that should happen at genesis.

impl<T: Config<I>, I: 'static> OnIdle<<T as Config>::BlockNumber> for Pallet<T, I>

fn on_idle(n: <T as Config>::BlockNumber, remaining_weight: Weight) -> Weight

The block is being finalized. Implement to have something happen in case there is leftover weight. Check the passed remaining_weight to make sure it is high enough to allow for your pallet’s extra computation.

impl<T: Config<I>, I: 'static> OnInitialize<<T as Config>::BlockNumber> for Pallet<T, I>

fn on_initialize(n: <T as Config>::BlockNumber) -> Weight

The block is being initialized. Implement to have something happen.

impl<T: Config<I>, I: 'static> OnRuntimeUpgrade for Pallet<T, I>

fn on_runtime_upgrade() -> Weight

Perform a module upgrade.

fn pre_upgrade() -> Result<(), &'static str>

Execute some pre-checks prior to a runtime upgrade.

fn post_upgrade() -> Result<(), &'static str>

Execute some post-checks after a runtime upgrade.

impl<T: Config<I>, I: 'static> PalletInfoAccess for Pallet<T, I>

fn index() -> usize

Index of the pallet as configured in the runtime.

fn name() -> &'static str

Name of the pallet as configured in the runtime.

impl<T, I> PartialEq<Pallet<T, I>> for Pallet<T, I>

fn eq(&self, other: &Self) -> bool

This method tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

This method tests for !=.

impl<T: Config<I>, I: 'static> ReservableCurrency<<T as Config>::AccountId> for Pallet<T, I> where
    T::Balance: MaybeSerializeDeserialize + Debug, 

fn can_reserve(who: &T::AccountId, value: Self::Balance) -> bool

Check if who can reserve value from their free balance.

Always true if value to be reserved is zero.

fn reserve(who: &T::AccountId, value: Self::Balance) -> DispatchResult

Move value from the free balance from who to their reserved balance.

Is a no-op if value to be reserved is zero.

fn unreserve(who: &T::AccountId, value: Self::Balance) -> Self::Balance

Unreserve some funds, returning any amount that was unable to be unreserved.

Is a no-op if the value to be unreserved is zero or the account does not exist.

fn slash_reserved(
    who: &T::AccountId,
    value: Self::Balance
) -> (Self::NegativeImbalance, Self::Balance)

Slash from reserved balance, returning the negative imbalance created, and any amount that was unable to be slashed.

Is a no-op if the value to be slashed is zero or the account does not exist.

fn repatriate_reserved(
    slashed: &T::AccountId,
    beneficiary: &T::AccountId,
    value: Self::Balance,
    status: Status
) -> Result<Self::Balance, DispatchError>

Move the reserved balance of one account into the balance of another, according to status.

Is a no-op if:

• the value to be moved is zero; or
• the slashed id equal to beneficiary and the status is Reserved.

fn reserved_balance(who: &T::AccountId) -> Self::Balance

The amount of the balance of a given account that is externally reserved; this can still get slashed, but gets slashed last of all.

impl<T: Config<I>, I: 'static> StorageInfoTrait for Pallet<T, I>

fn storage_info() -> Vec<StorageInfo>

impl<T: Config<I>, I: 'static> Transfer<<T as Config>::AccountId> for Pallet<T, I>

fn transfer(
    source: &T::AccountId,
    dest: &T::AccountId,
    amount: T::Balance,
    keep_alive: bool
) -> Result<T::Balance, DispatchError>

Transfer funds from one account into another.

impl<T: Config<I>, I: 'static> Unbalanced<<T as Config>::AccountId> for Pallet<T, I>

fn set_balance(who: &T::AccountId, amount: Self::Balance) -> DispatchResult

Set the balance of who to amount. If this cannot be done for some reason (e.g. because the account cannot be created or an overflow) then an Err is returned.

fn set_total_issuance(amount: Self::Balance)

Set the total issuance to amount.

fn decrease_balance(
    who: &AccountId,
    amount: Self::Balance
) -> Result<Self::Balance, DispatchError>

Reduce the balance of who by amount. If it cannot be reduced by that amount for some reason, return Err and don’t reduce it at all. If Ok, return the imbalance.

fn decrease_balance_at_most(
    who: &AccountId,
    amount: Self::Balance
) -> Self::Balance

Reduce the balance of who by the most that is possible, up to amount.

fn increase_balance(
    who: &AccountId,
    amount: Self::Balance
) -> Result<Self::Balance, DispatchError>

Increase the balance of who by amount. If it cannot be increased by that amount for some reason, return Err and don’t increase it at all. If Ok, return the imbalance.

fn increase_balance_at_most(
    who: &AccountId,
    amount: Self::Balance
) -> Self::Balance

Increase the balance of who by the most that is possible, up to amount.

impl<T, I> Eq for Pallet<T, I>