curvefi / curve-dao-contracts Goto Github PK

# @version 0.2.12
"""
@title Voting Escrow
@author Curve Finance & Polars.io
@license MIT
@notice Votes have a weight depending on time, so that users are
        committed to the future of (whatever they are voting for)
@dev Vote weight decays linearly over time. Lock time cannot be
     more than `MAXTIME` (4 years).
"""

# Voting escrow to have time-weighted votes
# Votes have a weight depending on time, so that users are committed
# to the future of (whatever they are voting for).
# The weight in this implementation is linear, and lock cannot be more than maxtime:
# w ^
# 1 +        /
#   |      /
#   |    /
#   |  /
#   |/
# 0 +--------+------> time
#       maxtime (4 years?)

struct Point:
    bias: int128
    slope: int128  # - dweight / dt
    ts: uint256
    blk: uint256  # block
# We cannot really do block numbers per se b/c slope is per time, not per block
# and per block could be fairly bad b/c Ethereum changes blocktimes.
# What we can do is to extrapolate ***At functions

struct LockedBalance:
    amount: int128
    end: uint256


interface ERC20:
    def decimals() -> uint256: view
    def name() -> String[64]: view
    def symbol() -> String[32]: view
    def transfer(to: address, amount: uint256) -> bool: nonpayable
    def transferFrom(spender: address, to: address, amount: uint256) -> bool: nonpayable


# Interface for checking whether address belongs to a whitelisted
# type of a smart wallet.
# When new types are added - the whole contract is changed
# The check() method is modifying to be able to use caching
# for individual wallet addresses
interface SmartWalletChecker:
    def check(addr: address) -> bool: nonpayable

DEPOSIT_FOR_TYPE: constant(int128) = 0
CREATE_LOCK_TYPE: constant(int128) = 1
INCREASE_LOCK_AMOUNT: constant(int128) = 2
INCREASE_UNLOCK_TIME: constant(int128) = 3

event Deposit:
    provider: indexed(address)
    value: uint256
    locktime: indexed(uint256)
    type: int128
    ts: uint256

event Withdraw:
    provider: indexed(address)
    value: uint256
    ts: uint256

event Supply:
    prevSupply: uint256
    supply: uint256


WEEK: constant(uint256) = 7 * 86400  # all future times are rounded by week
MAXTIME: constant(uint256) = 4 * 365 * 86400  # 4 years
MULTIPLIER: constant(uint256) = 10 ** 18

token: public(address)
supply: public(uint256)

locked: public(HashMap[address, LockedBalance])

epoch: public(uint256)
point_history: public(Point[100000000000000000000000000000])  # epoch -> unsigned point
user_point_history: public(HashMap[address, Point[1000000000]])  # user -> Point[user_epoch]
user_point_epoch: public(HashMap[address, uint256])
slope_changes: public(HashMap[uint256, int128])  # time -> signed slope change

# Aragon's view methods for compatibility
controller: public(address)
transfersEnabled: public(bool)

name: public(String[64])
symbol: public(String[32])
version: public(String[32])
decimals: public(uint256)

# Checker for whitelisted (smart contract) wallets which are allowed to deposit
# The goal is to prevent tokenizing the escrow
future_smart_wallet_checker: public(address)
smart_wallet_checker: public(address)


@external
def __init__(token_addr: address, _name: String[64], _symbol: String[32], _version: String[32]):
    """
    @notice Contract constructor
    @param token_addr `ERC20CRV` token address
    @param _name Token name
    @param _symbol Token symbol
    @param _version Contract version - required for Aragon compatibility
    """
    self.token = token_addr
    self.point_history[0].blk = block.number
    self.point_history[0].ts = block.timestamp
    self.controller = msg.sender
    self.transfersEnabled = True

    _decimals: uint256 = ERC20(token_addr).decimals()
    assert _decimals <= 255
    self.decimals = _decimals

    self.name = _name
    self.symbol = _symbol
    self.version = _version


@external
@view
def get_last_user_slope(addr: address) -> int128:
    """
    @notice Get the most recently recorded rate of voting power decrease for `addr`
    @param addr Address of the user wallet
    @return Value of the slope
    """
    uepoch: uint256 = self.user_point_epoch[addr]
    return self.user_point_history[addr][uepoch].slope


@external
@view
def user_point_history__ts(_addr: address, _idx: uint256) -> uint256:
    """
    @notice Get the timestamp for checkpoint `_idx` for `_addr`
    @param _addr User wallet address
    @param _idx User epoch number
    @return Epoch time of the checkpoint
    """
    return self.user_point_history[_addr][_idx].ts


@external
@view
def locked__end(_addr: address) -> uint256:
    """
    @notice Get timestamp when `_addr`'s lock finishes
    @param _addr User wallet
    @return Epoch time of the lock end
    """
    return self.locked[_addr].end


@internal
def _checkpoint(addr: address, old_locked: LockedBalance, new_locked: LockedBalance):
    """
    @notice Record global and per-user data to checkpoint
    @param addr User's wallet address. No user checkpoint if 0x0
    @param old_locked Pevious locked amount / end lock time for the user
    @param new_locked New locked amount / end lock time for the user
    """
    u_old: Point = empty(Point)
    u_new: Point = empty(Point)
    old_dslope: int128 = 0
    new_dslope: int128 = 0
    _epoch: uint256 = self.epoch

    if addr != ZERO_ADDRESS:
        # Calculate slopes and biases
        # Kept at zero when they have to
        if old_locked.end > block.timestamp and old_locked.amount > 0:
            u_old.slope = old_locked.amount / MAXTIME
            u_old.bias = u_old.slope * convert(old_locked.end - block.timestamp, int128)
        if new_locked.end > block.timestamp and new_locked.amount > 0:
            u_new.slope = new_locked.amount / MAXTIME
            u_new.bias = u_new.slope * convert(new_locked.end - block.timestamp, int128)

        # Read values of scheduled changes in the slope
        # old_locked.end can be in the past and in the future
        # new_locked.end can ONLY by in the FUTURE unless everything expired: than zeros
        old_dslope = self.slope_changes[old_locked.end]
        if new_locked.end != 0:
            if new_locked.end == old_locked.end:
                new_dslope = old_dslope
            else:
                new_dslope = self.slope_changes[new_locked.end]

    last_point: Point = Point({bias: 0, slope: 0, ts: block.timestamp, blk: block.number})
    if _epoch > 0:
        last_point = self.point_history[_epoch]
    last_checkpoint: uint256 = last_point.ts
    # initial_last_point is used for extrapolation to calculate block number
    # (approximately, for *At methods) and save them
    # as we cannot figure that out exactly from inside the contract
    initial_last_point: Point = last_point
    block_slope: uint256 = 0  # dblock/dt
    if block.timestamp > last_point.ts:
        block_slope = MULTIPLIER * (block.number - last_point.blk) / (block.timestamp - last_point.ts)
    # If last point is already recorded in this block, slope=0
    # But that's ok b/c we know the block in such case

    # Go over weeks to fill history and calculate what the current point is
    t_i: uint256 = (last_checkpoint / WEEK) * WEEK
    for i in range(255):
        # Hopefully it won't happen that this won't get used in 5 years!
        # If it does, users will be able to withdraw but vote weight will be broken
        t_i += WEEK
        d_slope: int128 = 0
        if t_i > block.timestamp:
            t_i = block.timestamp
        else:
            d_slope = self.slope_changes[t_i]
        last_point.bias -= last_point.slope * convert(t_i - last_checkpoint, int128)
        last_point.slope += d_slope
        if last_point.bias < 0:  # This can happen
            last_point.bias = 0
        if last_point.slope < 0:  # This cannot happen - just in case
            last_point.slope = 0
        last_checkpoint = t_i
        last_point.ts = t_i
        last_point.blk = initial_last_point.blk + block_slope * (t_i - initial_last_point.ts) / MULTIPLIER
        _epoch += 1
        if t_i == block.timestamp:
            last_point.blk = block.number
            break
        else:
            self.point_history[_epoch] = last_point

    self.epoch = _epoch
    # Now point_history is filled until t=now

    if addr != ZERO_ADDRESS:
        # If last point was in this block, the slope change has been applied already
        # But in such case we have 0 slope(s)
        last_point.slope += (u_new.slope - u_old.slope)
        last_point.bias += (u_new.bias - u_old.bias)
        if last_point.slope < 0:
            last_point.slope = 0
        if last_point.bias < 0:
            last_point.bias = 0

    # Record the changed point into history
    self.point_history[_epoch] = last_point

    if addr != ZERO_ADDRESS:
        # Schedule the slope changes (slope is going down)
        # We subtract new_user_slope from [new_locked.end]
        # and add old_user_slope to [old_locked.end]
        if old_locked.end > block.timestamp:
            # old_dslope was <something> - u_old.slope, so we cancel that
            old_dslope += u_old.slope
            if new_locked.end == old_locked.end:
                old_dslope -= u_new.slope  # It was a new deposit, not extension
            self.slope_changes[old_locked.end] = old_dslope

        if new_locked.end > block.timestamp:
            if new_locked.end > old_locked.end:
                new_dslope -= u_new.slope  # old slope disappeared at this point
                self.slope_changes[new_locked.end] = new_dslope
            # else: we recorded it already in old_dslope

        # Now handle user history
        user_epoch: uint256 = self.user_point_epoch[addr] + 1

        self.user_point_epoch[addr] = user_epoch
        u_new.ts = block.timestamp
        u_new.blk = block.number
        self.user_point_history[addr][user_epoch] = u_new


@internal
def _deposit_for(_addr: address, _value: uint256, unlock_time: uint256, locked_balance: LockedBalance, type: int128):
    """
    @notice Deposit and lock tokens for a user
    @param _addr User's wallet address
    @param _value Amount to deposit
    @param unlock_time New time when to unlock the tokens, or 0 if unchanged
    @param locked_balance Previous locked amount / timestamp
    """
    _locked: LockedBalance = locked_balance
    supply_before: uint256 = self.supply

    self.supply = supply_before + _value
    old_locked: LockedBalance = _locked
    # Adding to existing lock, or if a lock is expired - creating a new one
    _locked.amount += convert(_value, int128)
    if unlock_time != 0:
        _locked.end = unlock_time
    self.locked[_addr] = _locked

    # Possibilities:
    # Both old_locked.end could be current or expired (>/< block.timestamp)
    # value == 0 (extend lock) or value > 0 (add to lock or extend lock)
    # _locked.end > block.timestamp (always)
    self._checkpoint(_addr, old_locked, _locked)

    if _value != 0:
        assert ERC20(self.token).transferFrom(_addr, self, _value)

    log Deposit(_addr, _value, _locked.end, type, block.timestamp)
    log Supply(supply_before, supply_before + _value)


@internal
def _passive_deposit_for(_addr: address, _value: uint256, unlock_time: uint256, locked_balance: LockedBalance, type: int128):
    """
    @notice Deposit and lock tokens for a user
    @param _addr User's wallet address
    @param _value Amount to deposit
    @param unlock_time New time when to unlock the tokens, or 0 if unchanged
    @param locked_balance Previous locked amount / timestamp
    """
    _locked: LockedBalance = locked_balance
    supply_before: uint256 = self.supply

    self.supply = supply_before + _value
    old_locked: LockedBalance = _locked
    # Adding to existing lock, or if a lock is expired - creating a new one
    _locked.amount += convert(_value, int128)
    if unlock_time != 0:
        _locked.end = unlock_time
    self.locked[_addr] = _locked

    # Possibilities:
    # Both old_locked.end could be current or expired (>/< block.timestamp)
    # value == 0 (extend lock) or value > 0 (add to lock or extend lock)
    # _locked.end > block.timestamp (always)
    self._checkpoint(_addr, old_locked, _locked)

    log Deposit(_addr, _value, _locked.end, type, block.timestamp)
    log Supply(supply_before, supply_before + _value)


@external
def checkpoint():
    """
    @notice Record global data to checkpoint
    """
    self._checkpoint(ZERO_ADDRESS, empty(LockedBalance), empty(LockedBalance))


@external
@nonreentrant('lock')
def deposit_for(_addr: address, _value: uint256):
    """
    @notice Deposit `_value` tokens for `_addr` and add to the lock
    @dev Anyone (even a smart contract) can deposit for someone else, but
         cannot extend their locktime and deposit for a brand new user
    @param _addr User's wallet address
    @param _value Amount to add to user's lock
    """
    _locked: LockedBalance = self.locked[_addr]

    assert _value > 0  # dev: need non-zero value
    assert _locked.amount > 0, "No existing lock found"
    assert _locked.end > block.timestamp, "Cannot add to expired lock. Withdraw"

    self._deposit_for(_addr, _value, 0, self.locked[_addr], DEPOSIT_FOR_TYPE)


@external
@nonreentrant('lock')
def create_lock(_value: uint256, _unlock_time: uint256):
    """
    @notice Deposit `_value` tokens for `msg.sender` and lock until `_unlock_time`
    @param _value Amount to deposit
    @param _unlock_time Epoch time when tokens unlock, rounded down to whole weeks
    """
    if msg.sender != tx.origin:
        raise "Smart contract depositors not allowed"

    unlock_time: uint256 = (_unlock_time / WEEK) * WEEK  # Locktime is rounded down to weeks
    _locked: LockedBalance = self.locked[msg.sender]

    assert _value > 0  # dev: need non-zero value
    assert _locked.amount == 0, "Withdraw old tokens first"
    assert unlock_time > block.timestamp, "Can only lock until time in the future"
    assert unlock_time <= block.timestamp + MAXTIME, "Voting lock can be 4 years max"

    self._deposit_for(msg.sender, _value, unlock_time, _locked, CREATE_LOCK_TYPE)


@external
@nonreentrant('lock')
def create_lock_for_origin(_value: uint256, _unlock_time: uint256):
    """
    @notice Deposit `_value` tokens for `tx.origin` and lock until `_unlock_time`
    @param _value Amount to deposit
    @param _unlock_time Epoch time when tokens unlock, rounded down to whole weeks
    """
    assert self.crowdsale == msg.sender, "Sender should be crowdsale"
    unlock_time: uint256 = (_unlock_time / WEEK) * WEEK  # Locktime is rounded down to weeks
    _locked: LockedBalance = self.locked[tx.origin]

    assert _value > 0  # dev: need non-zero value
    assert _locked.amount == 0, "Withdraw old tokens first"
    assert unlock_time > block.timestamp, "Can only lock until time in the future"
    assert unlock_time <= block.timestamp + MAXTIME, "Voting lock can be 4 years max"

    self._passive_deposit_for(tx.origin, _value, unlock_time, _locked, CREATE_LOCK_TYPE)


@external
@nonreentrant('lock')
def increase_amount(_value: uint256):
    """
    @notice Deposit `_value` additional tokens for `msg.sender`
            without modifying the unlock time
    @param _value Amount of tokens to deposit and add to the lock
    """
    _locked: LockedBalance = self.locked[msg.sender]

    assert _value > 0  # dev: need non-zero value
    assert _locked.amount > 0, "No existing lock found"
    assert _locked.end > block.timestamp, "Cannot add to expired lock. Withdraw"

    self._deposit_for(msg.sender, _value, 0, _locked, INCREASE_LOCK_AMOUNT)


@external
@nonreentrant('lock')
def increase_unlock_time(_unlock_time: uint256):
    """
    @notice Extend the unlock time for `msg.sender` to `_unlock_time`
    @param _unlock_time New epoch time for unlocking
    """
    _locked: LockedBalance = self.locked[msg.sender]
    unlock_time: uint256 = (_unlock_time / WEEK) * WEEK  # Locktime is rounded down to weeks

    assert _locked.end > block.timestamp, "Lock expired"
    assert _locked.amount > 0, "Nothing is locked"
    assert unlock_time > _locked.end, "Can only increase lock duration"
    assert unlock_time <= block.timestamp + MAXTIME, "Voting lock can be 4 years max"

    self._deposit_for(msg.sender, 0, unlock_time, _locked, INCREASE_UNLOCK_TIME)


@external
@nonreentrant('lock')
def withdraw():
    """
    @notice Withdraw all tokens for `msg.sender`
    @dev Only possible if the lock has expired
    """
    _locked: LockedBalance = self.locked[msg.sender]
    assert block.timestamp >= _locked.end, "The lock didn't expire"
    value: uint256 = convert(_locked.amount, uint256)

    old_locked: LockedBalance = _locked
    _locked.end = 0
    _locked.amount = 0
    self.locked[msg.sender] = _locked
    supply_before: uint256 = self.supply
    self.supply = supply_before - value

    # old_locked can have either expired <= timestamp or zero end
    # _locked has only 0 end
    # Both can have >= 0 amount
    self._checkpoint(msg.sender, old_locked, _locked)

    assert ERC20(self.token).transfer(msg.sender, value)

    log Withdraw(msg.sender, value, block.timestamp)
    log Supply(supply_before, supply_before - value)


# The following ERC20/minime-compatible methods are not real balanceOf and supply!
# They measure the weights for the purpose of voting, so they don't represent
# real coins.

@external
@view
def find_block_epoch(_block: uint256, max_epoch: uint256) -> uint256:
    """
    @notice Binary search to estimate timestamp for block number
    @param _block Block to find
    @param max_epoch Don't go beyond this epoch
    @return Approximate timestamp for block
    """
    # Binary search
    _min: uint256 = 0
    _max: uint256 = max_epoch
    for i in range(128):  # Will be always enough for 128-bit numbers
        if _min >= _max:
            break
        _mid: uint256 = (_min + _max + 1) / 2
        if self.point_history[_mid].blk <= _block:
            _min = _mid
        else:
            _max = _mid - 1
    return _min


crowdsale: public(address)
    

@external
def changeCrowdsale(_newCrowdsale: address):
    assert msg.sender == self.controller, "Caller should be controller"
    self.crowdsale = _newCrowdsale
    

brownie run scripts/deployment/deploy_dao.py development --network mainnet-fork

brownie run scripts/deployment/deploy_dao.py development --network mainnet-fork

  File "brownie/_cli/run.py", line 50, in main
    return_value, frame = run(
  File "brownie/project/scripts.py", line 103, in run
    return_value = f_locals[method_name](*args, **kwargs)
  File "./scripts/deployment/deploy_dao.py", line 70, in development
    deploy_part_two(accounts[0], token, voting_escrow)
  File "./scripts/deployment/deploy_dao.py", line 101, in deploy_part_two
    pool_proxy = PoolProxy.deploy({"from": admin, "required_confs": confs})
  File "brownie/network/contract.py", line 528, in __call__
    return tx["from"].deploy(
  File "brownie/network/account.py", line 509, in deploy
    data = contract.deploy.encode_input(*args)
  File "brownie/network/contract.py", line 557, in encode_input
    data = format_input(self.abi, args)
  File "brownie/convert/normalize.py", line 20, in format_input
    raise type(e)(f"{abi['name']} {e}") from None
ValueError: constructor Sequence has incorrect length, expected 3 but got 0

  File "brownie/_cli/run.py", line 50, in main
    return_value, frame = run(
  File "brownie/project/scripts.py", line 103, in run
    return_value = f_locals[method_name](*args, **kwargs)
  File "./scripts/deployment/deploy_dao.py", line 70, in development
    deploy_part_two(accounts[0], token, voting_escrow)
  File "./scripts/deployment/deploy_dao.py", line 115, in deploy_part_two
    gauge = LiquidityGauge.deploy(lp_token, minter, {"from": admin, "required_confs": confs})
  File "brownie/network/contract.py", line 528, in __call__
    return tx["from"].deploy(
  File "brownie/network/account.py", line 509, in deploy
    data = contract.deploy.encode_input(*args)
  File "brownie/network/contract.py", line 557, in encode_input
    data = format_input(self.abi, args)
  File "brownie/convert/normalize.py", line 20, in format_input
    raise type(e)(f"{abi['name']} {e}") from None
ValueError: constructor Sequence has incorrect length, expected 3 but got 2

  File "brownie/_cli/run.py", line 50, in main
    return_value, frame = run(
  File "brownie/project/scripts.py", line 103, in run
    return_value = f_locals[method_name](*args, **kwargs)
  File "./scripts/deployment/deploy_dao.py", line 70, in development
    deploy_part_two(accounts[0], token, voting_escrow)
  File "./scripts/deployment/deploy_dao.py", line 120, in deploy_part_two
    gauge = LiquidityGaugeReward.deploy(
  File "brownie/network/contract.py", line 528, in __call__
    return tx["from"].deploy(
  File "brownie/network/account.py", line 509, in deploy
    data = contract.deploy.encode_input(*args)
  File "brownie/network/contract.py", line 557, in encode_input
    data = format_input(self.abi, args)
  File "brownie/convert/normalize.py", line 20, in format_input
    raise type(e)(f"{abi['name']} {e}") from None
ValueError: constructor Sequence has incorrect length, expected 5 but got 4

brownie run scripts/deployment/deploy_dao.py development --network mainnet-fork

brownie test tests/unitary
brownie test tests/integration

WEEK: constant(uint256) = 7 * 86400  # all future times are rounded by week
MAXTIME: constant(uint256) = 4 * **365** * 86400  # 4 years
MULTIPLIER: constant(uint256) = 10 ** 18