2020-01-15 13:20:54 -08:00

212 lines
10 KiB
TypeScript

import { OwnerStakeByStatus, StakeInfo, StakeStatus, StoredBalance } from '@0x/contracts-staking';
import { constants } from '@0x/contracts-test-utils';
import { BigNumber } from '@0x/utils';
import '@azure/core-asynciterator-polyfill';
import * as _ from 'lodash';
import { AssertionResult } from '../assertions/function_assertion';
import { assetProxyTransferFailedAssertion } from '../assertions/generic_assertions';
import { validMoveStakeAssertion } from '../assertions/moveStake';
import { validStakeAssertion } from '../assertions/stake';
import { invalidUnstakeAssertion, validUnstakeAssertion } from '../assertions/unstake';
import { validWithdrawDelegatorRewardsAssertion } from '../assertions/withdrawDelegatorRewards';
import { Pseudorandom } from '../utils/pseudorandom';
import { Actor, Constructor } from './base';
export interface StakerInterface {
stakeAsync: (amount: BigNumber, poolId?: string) => Promise<void>;
}
/**
* This mixin encapsulates functionality associated with stakers within the 0x ecosystem.
* This includes staking ZRX (and optionally delegating it to a specific pool).
*/
export function StakerMixin<TBase extends Constructor>(Base: TBase): TBase & Constructor<StakerInterface> {
return class extends Base {
public stake: OwnerStakeByStatus;
public readonly actor: Actor;
/**
* The mixin pattern requires that this constructor uses `...args: any[]`, but this class
* really expects a single `ActorConfig` parameter (assuming `Actor` is used as the base
* class).
*/
constructor(...args: any[]) {
// tslint:disable-next-line:no-inferred-empty-object-type
super(...args);
this.actor = (this as any) as Actor;
this.actor.mixins.push('Staker');
this.stake = {
[StakeStatus.Undelegated]: new StoredBalance(),
[StakeStatus.Delegated]: { total: new StoredBalance() },
};
// Register this mixin's assertion generators
this.actor.simulationActions = {
...this.actor.simulationActions,
validStake: this._validStake(),
invalidStake: this._invalidStake(),
validUnstake: this._validUnstake(),
invalidUnstake: this._invalidUnstake(),
validMoveStake: this._validMoveStake(),
validWithdrawDelegatorRewards: this._validWithdrawDelegatorRewards(),
};
}
/**
* Stakes the given amount of ZRX. If `poolId` is provided, subsequently delegates the newly
* staked ZRX with that pool.
*/
public async stakeAsync(amount: BigNumber, poolId?: string): Promise<void> {
const { stakingWrapper } = this.actor.deployment.staking;
await stakingWrapper.stake(amount).awaitTransactionSuccessAsync({
from: this.actor.address,
});
if (poolId !== undefined) {
await stakingWrapper
.moveStake(
new StakeInfo(StakeStatus.Undelegated),
new StakeInfo(StakeStatus.Delegated, poolId),
amount,
)
.awaitTransactionSuccessAsync({ from: this.actor.address });
}
}
private async *_validStake(): AsyncIterableIterator<AssertionResult> {
const { zrx } = this.actor.deployment.tokens;
const { deployment, balanceStore } = this.actor.simulationEnvironment!;
const assertion = validStakeAssertion(deployment, this.actor.simulationEnvironment!, this.stake);
while (true) {
await balanceStore.updateErc20BalancesAsync();
const zrxBalance = balanceStore.balances.erc20[this.actor.address][zrx.address];
const amount = Pseudorandom.integer(0, zrxBalance);
yield assertion.executeAsync([amount], { from: this.actor.address });
}
}
private async *_invalidStake(): AsyncIterableIterator<AssertionResult> {
const { zrx } = this.actor.deployment.tokens;
const { deployment, balanceStore } = this.actor.simulationEnvironment!;
const assertion = assetProxyTransferFailedAssertion(deployment.staking.stakingWrapper, 'stake');
while (true) {
await balanceStore.updateErc20BalancesAsync();
const zrxBalance = balanceStore.balances.erc20[this.actor.address][zrx.address];
const amount = Pseudorandom.integer(zrxBalance, constants.MAX_UINT256);
yield assertion.executeAsync([amount], { from: this.actor.address });
}
}
private async *_validUnstake(): AsyncIterableIterator<AssertionResult> {
const { stakingWrapper } = this.actor.deployment.staking;
const { deployment, balanceStore } = this.actor.simulationEnvironment!;
const assertion = validUnstakeAssertion(deployment, this.actor.simulationEnvironment!, this.stake);
while (true) {
await balanceStore.updateErc20BalancesAsync();
const undelegatedStake = await stakingWrapper
.getOwnerStakeByStatus(this.actor.address, StakeStatus.Undelegated)
.callAsync();
const withdrawableStake = BigNumber.min(
undelegatedStake.currentEpochBalance,
undelegatedStake.nextEpochBalance,
);
const amount = Pseudorandom.integer(0, withdrawableStake);
yield assertion.executeAsync([amount], { from: this.actor.address });
}
}
private async *_invalidUnstake(): AsyncIterableIterator<AssertionResult> {
const { stakingWrapper } = this.actor.deployment.staking;
const { deployment, balanceStore } = this.actor.simulationEnvironment!;
while (true) {
await balanceStore.updateErc20BalancesAsync();
const undelegatedStake = await stakingWrapper
.getOwnerStakeByStatus(this.actor.address, StakeStatus.Undelegated)
.callAsync();
const withdrawableStake = BigNumber.min(
undelegatedStake.currentEpochBalance,
undelegatedStake.nextEpochBalance,
);
const assertion = invalidUnstakeAssertion(deployment, withdrawableStake);
const amount = Pseudorandom.integer(withdrawableStake, constants.MAX_UINT256);
yield assertion.executeAsync([amount], { from: this.actor.address });
}
}
private async *_validMoveStake(): AsyncIterableIterator<AssertionResult> {
const { deployment, stakingPools } = this.actor.simulationEnvironment!;
const assertion = validMoveStakeAssertion(deployment, this.actor.simulationEnvironment!, this.stake);
while (true) {
const { currentEpoch } = this.actor.simulationEnvironment!;
// Pick a random pool that this staker has delegated to (undefined if no such pools exist)
const fromPoolId = Pseudorandom.sample(
Object.keys(_.omit(this.stake[StakeStatus.Delegated], ['total'])),
);
// The `from` status must be Undelegated if the staker isn't delegated to any pools
// at the moment, or if the chosen pool is unfinalized
const fromStatus =
fromPoolId === undefined || stakingPools[fromPoolId].lastFinalized.isLessThan(currentEpoch.minus(1))
? StakeStatus.Undelegated
: (Pseudorandom.sample(
[StakeStatus.Undelegated, StakeStatus.Delegated],
[0.2, 0.8], // 20% chance of `Undelegated`, 80% chance of `Delegated`
) as StakeStatus);
const from = new StakeInfo(fromStatus, fromPoolId);
// Pick a random pool to move the stake to
const toPoolId = Pseudorandom.sample(Object.keys(stakingPools));
// The `from` status must be Undelegated if no pools exist in the simulation yet,
// or if the chosen pool is unfinalized
const toStatus =
toPoolId === undefined || stakingPools[toPoolId].lastFinalized.isLessThan(currentEpoch.minus(1))
? StakeStatus.Undelegated
: (Pseudorandom.sample(
[StakeStatus.Undelegated, StakeStatus.Delegated],
[0.2, 0.8], // 20% chance of `Undelegated`, 80% chance of `Delegated`
) as StakeStatus);
const to = new StakeInfo(toStatus, toPoolId);
// The next epoch balance of the `from` stake is the amount that can be moved
const moveableStake =
from.status === StakeStatus.Undelegated
? this.stake[StakeStatus.Undelegated].nextEpochBalance
: this.stake[StakeStatus.Delegated][from.poolId].nextEpochBalance;
const amount = Pseudorandom.integer(0, moveableStake);
yield assertion.executeAsync([from, to, amount], { from: this.actor.address });
}
}
private async *_validWithdrawDelegatorRewards(): AsyncIterableIterator<AssertionResult | void> {
const { stakingPools } = this.actor.simulationEnvironment!;
const assertion = validWithdrawDelegatorRewardsAssertion(
this.actor.deployment,
this.actor.simulationEnvironment!,
);
while (true) {
const prevEpoch = this.actor.simulationEnvironment!.currentEpoch.minus(1);
// Pick a finalized pool
const poolId = Pseudorandom.sample(
Object.keys(stakingPools).filter(id =>
stakingPools[id].lastFinalized.isGreaterThanOrEqualTo(prevEpoch),
),
);
if (poolId === undefined) {
yield;
} else {
yield assertion.executeAsync([poolId], { from: this.actor.address });
}
}
}
};
}
export class Staker extends StakerMixin(Actor) {}