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Uniswap V1 ABI "duplicate output parameter "out" in function removeLiquidity" error thrown

See original GitHub issue

When using ethers@v5 and loading the Uniswap V1 ABI I get “duplicate output parameter “out” in function removeLiquidity” error thrown.

ABI Culprit

{
    "name": "removeLiquidity",
    "outputs": [
      { "type": "uint256", "name": "out" },
      { "type": "uint256", "name": "out" }
    ],
    "inputs": [
      { "type": "uint256", "name": "amount" },
      { "type": "uint256", "name": "min_eth" },
      { "type": "uint256", "name": "min_tokens" },
      { "type": "uint256", "name": "deadline" }
    ],
    "constant": false,
    "payable": false,
    "type": "function",
    "gas": 116814
  },

Not sure if I should report this error here, because it seems like a Uniswap problem when Vyper compiles the ABI, but seeing as it’s unlikely to change, I thought it would be worth reporting because Uniswap is obviously super popular and people are going to use the generated ABI when V5 gets released.

Reference to the Vyper Smart Contract

https://github.com/Uniswap/uniswap-v1/blob/master/contracts/uniswap_exchange.vy#L83

Issue Analytics

State:
Created 3 years ago
Comments:7 (5 by maintainers)

Top GitHub Comments

1reaction

ricmoocommented, May 14, 2020

Coolio. I’ll close this now then, but if you still have any problem, please re-open.

Thanks! 😃

1reaction

ricmoocommented, May 13, 2020

This has been added to 5.0.0-beta.187. Try it out and let me know if you still have any problems. 😃

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