Uniswap V3未收费用计算

Question

根据白皮书，当一个位置在范围内时

未收费用=流动性( feeGrowthGlobal - feeGrowthOutsidelowerTick - feeGrowthOutsideUpperTick - feeGrowthInside)

但对于稳定的硬币，feeGrowthGlobal - feeGrowthOutsideLowerTick - feeGrowthOutsideUpperTick似乎是负的，导致负的未收取的费用。

示例

 {
        "id": "149982",
        "liquidity": "70751535817529022692995",
        "pool": {
          "feeGrowthGlobal0X128": "1218682304163016184766177108699434636279"
        },
        "tickLower": {
          "feeGrowthOutside0X128": "1145577432605598277662216874263285465942"
        },
        "tickUpper": {
          "feeGrowthOutside0X128": "1125981180184479101654443162252506477054"
        },
        "token0": {
          "symbol": "DAI"
        },
        "token1": {
          "symbol": "WETH"
        }
      },

1218682304163016184766177108699434636279 - 1145577432605598277662216874263285465942 - 1125981180184479101654443162252506477054 = -1052876308627061194550482927816357306717

Answer 1

我的两分钱：

我编写了一个函数，该函数执行静态调用，在其他函数中传递最大可收集值，以查看要收集多少挂起。

export const calculatePendingFees = async (
  tokenId: number,
  recipient: string,
  amount0Max: BigNumber,
  amount1Max: BigNumber,
  chainId: number
) => {
  try {
    const params = {
      tokenId: tokenId,
      recipient: recipient,
      amount0Max: amount0Max,
      amount1Max: amount1Max,
    }

    const nonfungible = new ethers.Contract(
      NONFUNGIBLE_POSITION_MANAGER_ADDRESS[chainId],
      Nonfungiblepositionmanager.abi,
      PROVIDER[chainId]
    )

    const feesGenerated = await nonfungible.callStatic.collect(params)
    return feesGenerated
  } catch (error) {
    console.log(error.message, "calculate fees error")
  }
}

对于amount0Max和amount1Max，您可以使用以下内容：

const MAX_UINT128 = BigNumber.from(2).pow(128).sub(1)

此函数将返回未收取的费用:)

Answer 2

在对无符号整数值进行数学计算时，需要考虑潜在的流量低于或过流的情况。更具体地说，Uniswap V3契约期望feeGrowthGlobal - feeGrowthOutsideLowerTick - feeGrowthOutsideUpperTick公式包装-大约256位(即模块)，如果您的语言本机实现BigInts (例如BigInts)，这可能会令人惊讶。例如，我的Python Pyuv3正确地处理了这个问题。