@chorus-one/ton/test/pool-staker.spec.ts

All-in-one tooling for building staking dApps on TON

import { toNano } from '@ton/ton'
import { TonPoolStaker } from '@chorus-one/ton'
import { describe, it } from 'mocha'
import { expect } from 'chai'

describe('TonPoolStaker_selectPool', () => {
  it('should prioritize the pool that has not reached minStake', () => {
    const result = TonPoolStaker.selectPool(200n, [100n, 300n])
    expect(result).to.equal(0) // Pool 1 needs to reach minStake
  })

  it('should prioritize the pool with a higher balance if both are below minStake', () => {
    const result = TonPoolStaker.selectPool(200n, [100n, 150n])
    expect(result).to.equal(1) // Pool 2 has a higher balance
  })

  it('should balance the pools if both have reached minStake', () => {
    const result = TonPoolStaker.selectPool(200n, [400n, 300n])
    expect(result).to.equal(1) // Pool 2 has a smaller balance
  })
})

describe('TonPoolStaker_calculateUnstakePoolAmount', () => {
  const fn = TonPoolStaker.calculateUnstakePoolAmount
  const minElectionStake = 10n

  describe('should keep both pools active, amount <= maxUnstakeKeepPool1Active + maxUnstakeKeepPool2Active', () => {
    // pool1: maxUnstakeKeepPoolActive (5n) < maxUnstakeKeepPoolAboveMin (10n)
    // pool2: maxUnstakeKeepPoolActive (10n) == maxUnstakeKeepPoolAboveMin (10n)
    // balance 1 < balance 2
    it('should unstake maxUnstakeKeepPoolActive partially, while prioritizing pool balance', () => {
      const result = fn(5n, minElectionStake, [15n, 20n], [10n, 10n], [0n, 0n], [0n, 0n])
      expect(result).to.deep.equal([0n, 5n])
    })

    // pool1: maxUnstakeKeepPoolActive (5n) < maxUnstakeKeepPoolAboveMin (10n)
    // pool2: maxUnstakeKeepPoolActive (10n) == maxUnstakeKeepPoolAboveMin (10n)
    it('should unstake maxUnstakeKeepPoolActive fully and maxUnstakeKeepPoolActive fully', () => {
      const result = fn(15n, minElectionStake, [15n, 20n], [10n, 10n], [0n, 0n], [0n, 0n])
      expect(result).to.deep.equal([5n, 10n])
    })

    // pool1: maxUnstakeKeepPoolActive (5n) > maxUnstakeKeepPoolAboveMin (3n)
    // pool2: maxUnstakeKeepPoolActive (10n) > maxUnstakeKeepPoolAboveMin (3n)
    it('should unstake maxUnstakeKeepPoolActive partially and maxUnstakeKeepPoolAboveMin fully, when maxUnstakeKeepPoolActive > maxUnstakeKeepPoolAboveMin', () => {
      const result = fn(5n, minElectionStake, [15n, 20n], [10n, 10n], [7n, 7n], [0n, 0n])
      expect(result).to.deep.equal([2n, 3n])
    })
  })

  describe('should disable pool with lowest balance, amount >= maxUnstakeKeepPool1Active + maxUnstakeKeepPool2AboveMin', () => {
    it('should unstake maxUnstakeKeepPoolActive fully and maxUnstakeKeepPoolAboveMin fully', () => {
      const result = fn(8n, minElectionStake, [13n, 12n], [10n, 10n], [5n, 5n], [0n, 0n])
      expect(result).to.deep.equal([3n, 5n])
    })

    it('should unstake maxUnstakeKeepPoolActive fully and maxUnstakeKeepPoolAboveMin partially', () => {
      const result = fn(6n, minElectionStake, [13n, 12n], [10n, 10n], [5n, 5n], [0n, 0n])
      expect(result).to.deep.equal([3n, 3n])
    })

    it('should unstake maxUnstakeKeepPoolActive fully and userMaxUnstakeAbsolute', () => {
      const result = fn(13n, minElectionStake, [13n, 12n], [10n, 10n], [5n, 5n], [0n, 0n])
      expect(result).to.deep.equal([3n, 10n])
    })

    it('should unstake maxUnstakeKeepPoolActive partially and maxUnstakeKeepPoolAboveMin partially, when maxUnstakeKeepPoolActive > maxUnstakeKeepPoolAboveMin', () => {
      const result = fn(7n, minElectionStake, [20n, 10n], [10n, 10n], [5n, 5n], [0n, 0n])
      expect(result).to.deep.equal([5n, 2n])
    })
  })

  describe('should disable pool with highest balance, amount >= maxUnstakeKeepPool1AboveMin + maxUnstakeKeepPool2Active', () => {
    it('should unstake maxUnstakeKeepPoolAboveMin fully and maxUnstakeKeepPoolActive fully', () => {
      const result = fn(9n, minElectionStake, [13n, 12n], [10n, 5n], [3n, 3n], [0n, 0n])
      expect(result).to.deep.equal([7n, 2n])
    })

    it('should unstake maxUnstakeKeepPoolAboveMin partially and maxUnstakeKeepPoolActive fully', () => {
      const result = fn(8n, minElectionStake, [13n, 12n], [10n, 4n], [1n, 1n], [0n, 0n])
      expect(result).to.deep.equal([6n, 2n])
    })

    it('should unstake userMaxUnstakeAbsolute and maxUnstakeKeepPoolActive fully', () => {
      const result = fn(12n, minElectionStake, [13n, 12n], [10n, 4n], [1n, 1n], [0n, 0n])
      expect(result).to.deep.equal([10n, 2n])
    })
  })

  describe('should disable both pools', () => {
    it('should unstake maxUnstakeKeepPoolAboveMin fully and maxUnstakeKeepPoolAboveMin partially', () => {
      const result = fn(10n, minElectionStake, [13n, 12n], [11n, 11n], [5n, 5n], [0n, 0n])
      expect(result).to.deep.equal([6n, 4n])
    })

    it('should unstake maxUnstakeKeepPoolAboveMin fully and maxUnstakeKeepPoolAboveMin fully', () => {
      const result = fn(8n, minElectionStake, [13n, 13n], [12n, 12n], [8n, 8n], [0n, 0n])
      expect(result).to.deep.equal([4n, 4n])
    })

    it('should unstake maxUnstakeKeepPoolAboveMin fully and userMaxUnstakeAbsolute', () => {
      const result = fn(16n, minElectionStake, [15n, 15n], [12n, 12n], [8n, 8n], [0n, 0n])
      expect(result).to.deep.equal([4n, 12n])
    })
  })

  describe('should unstake all', () => {
    it('should unstake userMaxUnstakeAbsolute and userMaxUnstakeAbsolute above minElectionStake', () => {
      const result = fn(8n, minElectionStake, [32n, 40n], [5n, 3n], [0n, 0n], [0n, 0n])
      expect(result).to.deep.equal([5n, 3n])
    })

    it('should unstake userMaxUnstakeAbsolute and userMaxUnstakeAbsolute bellow minElectionStake', () => {
      const result = fn(10n, minElectionStake, [7n, 7n], [5n, 5n], [0n, 0n], [0n, 0n])
      expect(result).to.deep.equal([5n, 5n])
    })

    it('should unstake userMaxUnstakeAbsolute and userMaxUnstakeAbsolute above userMinStake', () => {
      const result = fn(24n, minElectionStake, [15n, 15n], [12n, 12n], [8n, 8n], [0n, 0n])
      expect(result).to.deep.equal([12n, 12n])
    })

    it('should unstake userMaxUnstakeAbsolute and userMaxUnstakeAbsolute bellow userMinStake', () => {
      const result = fn(4n, minElectionStake, [15n, 15n], [2n, 2n], [8n, 8n], [0n, 0n])
      expect(result).to.deep.equal([2n, 2n])
    })
  })

  describe('should unstake when bellow minElectionStake', () => {
    it('should unstake maxUnstakeKeepPoolAboveMin partially', () => {
      const result = fn(1n, minElectionStake, [7n, 7n], [5n, 5n], [3n, 3n], [0n, 0n])
      expect(result).to.deep.equal([0n, 1n])
    })

    it('should unstake maxUnstakeKeepPoolAboveMin fully', () => {
      const result = fn(4n, minElectionStake, [7n, 7n], [5n, 5n], [3n, 3n], [0n, 0n])
      expect(result).to.deep.equal([2n, 2n])
    })
  })

  describe('should reject invalid amounts', () => {
    it('should reject when trying to unstake more than available', () => {
      expect(() => fn(21n, 10n, [20n, 20n], [10n, 10n], [0n, 0n], [0n, 0n])).to.throw(
        'Requested amount exceeds available stakes'
      )
    })

    it('should reject when maxUnstakeToKeepPoolAboveMin is not enough', () => {
      expect(() => fn(10n, minElectionStake, [15n, 15n], [8n, 8n], [7n, 7n], [0n, 0n])).to.throw(
        'No valid combination to unstake requested amount'
      )
    })

    it('should reject when trying to partially withdraw pool bellow userMinStake', () => {
      expect(() => fn(7n, minElectionStake, [15n, 15n], [4n, 4n], [7n, 7n], [0n, 0n])).to.throw(
        'No valid combination to unstake requested amount'
      )
    })

    it('should reject when trying to partially withdraw pool bellow userMinStake and userWithdraw is not enough', () => {
      expect(() => fn(17n, minElectionStake, [15n, 20n], [10n, 10n], [7n, 7n], [6n, 6n])).to.throw(
        'No valid combination to unstake requested amount'
      )
    })
  })

  describe('should allow partial withdraw when pool is bellow userMinStake and user has ready to withdraw amounts', () => {
    // userStaked=[4n, 4n] < userMinStake = 7n
    it('should unstake userWithdraw partially', () => {
      const result = fn(2n, minElectionStake, [15n, 20n], [10n, 10n], [7n, 7n], [6n, 6n])
      expect(result).to.deep.equal([0n, 2n])
    })

    // userStaked=[4n, 4n] < userMinStake = 7n
    it('should unstake maxUnstakeAbsolute and userWithdraw fully', () => {
      const result = fn(16n, minElectionStake, [15n, 20n], [10n, 10n], [7n, 7n], [6n, 6n])
      expect(result).to.deep.equal([10n, 6n])
    })

    // userStaked=[4n, 4n] < userMinStake = 7n
    it('should unstake userWithdraw partially and userWithdraw fully', () => {
      const result = fn(7n, minElectionStake, [15n, 20n], [10n, 10n], [7n, 7n], [6n, 6n])
      expect(result).to.deep.equal([1n, 6n])
    })
  })
})

describe('TonPoolStaker_calculateStakeAmount', () => {
  const fn = TonPoolStaker.calculateStakePoolAmount
  const minPoolStakes = [1n, 1n] as [bigint, bigint]

  it('should equalize the pool stake if both pools are above min', () => {
    // strategy: both pools are above minStake, so our goal is to optimize the
    // balance for the pool stake
    const result = fn(1000n, 200n, [250n, 200n], minPoolStakes)
    expect(result).to.eql([475n, 525n])

    // if pool balances are equal, split the stake evenly
    // the lower balance
    const result_tw = fn(
      toNano(5), // to stake
      toNano(5), // minimum for election
      [toNano(10), toNano(10)], // current pool balances
      [toNano(1), toNano(1)] // minPoolStakes
    )
    expect(result_tw).to.eql([toNano(2.5), toNano(2.5)])

    // if there is no chance to equalize the stakes, stake to the pool with
    // the lower balance
    const result_two = fn(
      toNano(3), // to stake
      toNano(5), // minimum for election
      [toNano(5), toNano(10)], // current pool balances
      [toNano(1), toNano(1)] // minPoolStakes
    )
    expect(result_two).to.eql([toNano(3), toNano(0)])

    // if the amount is enough to balance the stakes do it
    const result_three = fn(
      toNano(5), // to stake
      toNano(5), // minimum for election
      [toNano(5), toNano(10)], // current pool balances
      [toNano(1), toNano(1)] // minPoolStakes
    )
    expect(result_three).to.eql([toNano(5), toNano(0)])

    // if the remainder ( 6 - (6 - 1) = 1 ) divided evenly (0.5) is not meeting
    // the minimum stake, try to fill up the pool with the lower balance and
    // push the whole remainder to the other pool
    const result_four = fn(
      toNano(6), // to stake
      toNano(5), // minimum for election
      [toNano(5), toNano(10)], // current pool balances
      [toNano(1), toNano(1)] // minPoolStakes
    )
    expect(result_four).to.eql([toNano(5), toNano(1)])

    // it's not possible to balance the stakes and keep the minimum stake
    // so resign from balancing the pool stake and simply split the
    // amount between the pools
    const result_five = fn(
      toNano(2.4), // to stake
      toNano(1.2), // minimum for election
      [toNano(1.871), toNano(1.7348)], // current pool balances
      [toNano(1.2), toNano(1.2)] // minPoolStakes
    )
    expect(result_five).to.eql([toNano(1.2), toNano(1.2)])

    // if the remainder as a whole is not meeting the minimum stake, stake it
    // with the lowest stake pool
    const result_six = fn(
      toNano(5.5), // to stake
      toNano(5), // minimum for election
      [toNano(5), toNano(10)], // current pool balances
      [toNano(1), toNano(1)] // minPoolStakes
    )
    expect(result_six).to.eql([toNano(5.5), toNano(0)])
  })

  it('should distribute stake if only one pool is below minimum', () => {
    // activate pool two with 500 and the remainder (500) split between two pools
    const result = fn(1000n, 1000n, [1500n, 500n], minPoolStakes)
    expect(result).to.eql([250n, 750n])

    const result_two = fn(1000n, 1000n, [500n, 1500n], minPoolStakes)
    expect(result_two).to.eql([750n, 250n])

    // ^^ at edge
    const result_three = fn(500n, 1000n, [500n, 1500n], minPoolStakes)
    expect(result_three).to.eql([500n, 0n])

    // if there is not enough to activate pool two, split stakes between
    // active/inactive pool
    //
    // strategy: user stake can't activate the pool two, so staking all to pool
    // two doesn't earn any rewards. Instead, split the stake between two pools
    // so that the other staker has a chance to bring pool one in the next
    // staking action but at the same time user can still earn rewards from the
    // active pool (half of his stake)
    const result_four = fn(300n, 1000n, [500n, 1500n], minPoolStakes)
    expect(result_four).to.eql([150n, 150n])

    const result_five = fn(300n, 1000n, [1500n, 500n], minPoolStakes)
    expect(result_five).to.eql([150n, 150n])
  })

  it('should distribute stake if both pools are below minimum', () => {
    // there is no chance to make both pools active, fill the one with
    // highest stake
    const result = fn(150n, 1000n, [300n, 400n], minPoolStakes)
    expect(result).to.eql([0n, 150n])

    // ^^ same case as but reversed pool stakes
    const result_reverse = fn(150n, 1000n, [400n, 300n], minPoolStakes)
    expect(result_reverse).to.eql([150n, 0n])

    // there is a chance to make second pool active
    //
    // strategy: user stake was used to activate one pool, the remainder can
    // either be staked with the second pool or split in between active/inactive
    // pool. In the first case user doesn't earn anything on inactive pool so in
    // below case that would 4150 (our of 10150) earning no rewards. In the
    // second case only 2075 doesn't earn rewards, but at least the portion of
    // it contributes to the inactive pool being elected with next staker
    const result_two = fn(10150n, 10000n, [3000n, 4000n], minPoolStakes)
    expect(result_two).to.eql([2075n, 8075n])

    // there is a chance to make second pool active
    // strategy: as above ^^ but reversed the pools
    const result_three = fn(650n, 1000n, [400n, 300n], minPoolStakes)
    expect(result_three).to.eql([625n, 25n])

    // there is a chance to make both pools active, split the stake
    // strategy: fill both pools to the minStake and split the rest. This way
    // user stake will benefit from both pools (as both pools have been just
    // activated with his stake)
    const result_four = fn(13150n, 10000n, [3000n, 4000n], minPoolStakes)
    expect(result_four).to.eql([7075n, 6075n])
  })
})