Uniswap V1 ABI not working well

[Codonyat]

I wish to read from Uniswap V1 smart contract:
const uniswapFactoryV1ABI = fs.readFileSync('./src/UniswapFactoryV1.json','utf8'); const contract = new ethers.Contract("0xc0a47dFe034B400B47bDaD5FecDa2621de6c4d95",uniswapFactoryV1ABI,wallet); contract.tokenCount().then(count => console.log(count.toNumber()));

but it throws an exception:
UnhandledPromiseRejectionWarning: Error: call revert exception (method="tokenCount()", errorSignature=null, errorArgs=[null], reason=null, code=CALL_EXCEPTION, version=abi/5.0.1)

However when I used the human-readable ABI
const uniswapFactoryV1ABI = ["function tokenCount() view returns(uint)"];
it works and returns a number.

The JSON ABI is obtained from Etherscan and I have verified that this exception does not occur with Uniswap v2.

[ricmoo]

Can you post the results of a console.dir(uniswapFactoryV1ABI, { depth: null })?

[Codonyat]

Yes, sir.

  '    {\r\n' +
  '       "name":"NewExchange",\r\n' +  
  '       "inputs":[\r\n' +
  '          {\r\n' +
  '             "type":"address",\r\n' +
  '             "name":"token",\r\n' +  
  '             "indexed":true\r\n' +   
  '          },\r\n' +
  '          {\r\n' +
  '             "type":"address",\r\n' +
  '             "name":"exchange",\r\n' +
  '             "indexed":true\r\n' +
  '          }\r\n' +
  '       ],\r\n' +
  '       "anonymous":false,\r\n' +
  '       "type":"event"\r\n' +
  '    },\r\n' +
  '    {\r\n' +
  '       "name":"initializeFactory",\r\n' +
  '       "outputs":[\r\n' +
  ' \r\n' +
  '       ],\r\n' +
  '       "inputs":[\r\n' +
  '          {\r\n' +
  '             "type":"address",\r\n' +
  '             "name":"template"\r\n' +
  '          }\r\n' +
  '       ],\r\n' +
  '       "constant":false,\r\n' +
  '       "payable":false,\r\n' +
  '       "type":"function",\r\n' +
  '       "gas":35725\r\n' +
  '    },\r\n' +
  '    {\r\n' +
  '       "name":"createExchange",\r\n' +
  '       "outputs":[\r\n' +
  '          {\r\n' +
  '             "type":"address",\r\n' +
  '             "name":"out"\r\n' +
  '          }\r\n' +
  '       ],\r\n' +
  '       "inputs":[\r\n' +
  '          {\r\n' +
  '             "type":"address",\r\n' +
  '             "name":"token"\r\n' +
  '          }\r\n' +
  '       ],\r\n' +
  '       "constant":false,\r\n' +
  '       "payable":false,\r\n' +
  '       "type":"function",\r\n' +
  '       "gas":187911\r\n' +
  '    },\r\n' +
  '    {\r\n' +
  '       "name":"getExchange",\r\n' +
  '       "outputs":[\r\n' +
  '          {\r\n' +
  '             "type":"address",\r\n' +
  '             "name":"out"\r\n' +
  '          }\r\n' +
  '       ],\r\n' +
  '       "inputs":[\r\n' +
  '          {\r\n' +
  '             "type":"address",\r\n' +
  '             "name":"token"\r\n' +
  '          }\r\n' +
  '       ],\r\n' +
  '       "constant":true,\r\n' +
  '       "payable":false,\r\n' +
  '       "type":"function",\r\n' +
  '       "gas":715\r\n' +
  '    },\r\n' +
  '    {\r\n' +
  '       "name":"getToken",\r\n' +
  '       "outputs":[\r\n' +
  '          {\r\n' +
  '             "type":"address",\r\n' +
  '             "name":"out"\r\n' +
  '          }\r\n' +
  '       ],\r\n' +
  '       "inputs":[\r\n' +
  '          {\r\n' +
  '             "type":"address",\r\n' +
  '             "name":"exchange"\r\n' +
  '          }\r\n' +
  '       ],\r\n' +
  '       "constant":true,\r\n' +
  '       "payable":false,\r\n' +
  '       "type":"function",\r\n' +
  '       "gas":745\r\n' +
  '    },\r\n' +
  '    {\r\n' +
  '       "name":"getTokenWithId",\r\n' +
  '       "outputs":[\r\n' +
  '          {\r\n' +
  '             "type":"address",\r\n' +
  '             "name":"out"\r\n' +
  '          }\r\n' +
  '       ],\r\n' +
  '       "inputs":[\r\n' +
  '          {\r\n' +
  '             "type":"uint256",\r\n' +
  '             "name":"token_id"\r\n' +
  '          }\r\n' +
  '       ],\r\n' +
  '       "constant":true,\r\n' +
  '       "payable":false,\r\n' +
  '       "type":"function",\r\n' +
  '       "gas":736\r\n' +
  '    },\r\n' +
  '    {\r\n' +
  '       "name":"exchangeTemplate",\r\n' +
  '       "outputs":[\r\n' +
  '          {\r\n' +
  '             "type":"address",\r\n' +
  '             "name":"out"\r\n' +
  '          }\r\n' +
  '       ],\r\n' +
  '       "inputs":[\r\n' +
  ' \r\n' +
  '       ],\r\n' +
  '       "constant":true,\r\n' +
  '       "payable":false,\r\n' +
  '       "type":"function",\r\n' +
  '       "gas":633\r\n' +
  '    },\r\n' +
  '    {\r\n' +
  '       "name":"tokenCount",\r\n' +
  '       "outputs":[\r\n' +
  '          {\r\n' +
  '             "type":"uint256",\r\n' +
  '             "name":"out"\r\n' +
  '          }\r\n' +
  '       ],\r\n' +
  '       "inputs":[\r\n' +
  ' \r\n' +
  '       ],\r\n' +
  '       "constant":true,\r\n' +
  '       "payable":false,\r\n' +
  '       "type":"function",\r\n' +
  '       "gas":663\r\n' +
  '    }\r\n' +
  ' ]'```

[jinchung]

I'm also facing a similar issue trying to read constant functions on the Uniswap v1 exchange contract after upgrading to ethers v5. With the v5 upgrade, it started giving me a call revert exception to read things like tokenAddress, balanceOf, totalSupply, etc. Interestingly, I don't get this issue when calling constant functions on other contracts (such as the ERC20 ABI) with v5.

I tried using the human-readable ABI as mentioned above, and that works fine.

• The contract addresses I'm using are Uniswap v1 liquidity pool token addresses (e.g, SAI pool: "0x09cabec1ead1c0ba254b09efb3ee13841712be14", DAI pool: "0x2a1530c4c41db0b0b2bb646cb5eb1a67b7158667")
• The ABI I'm using is: https://github.com/Uniswap/uniswap-v1/blob/master/abi/uniswap_exchange.json
• My provider is just the ethers JsonRpcProvider with an Infura url that includes my API key (doing all this on mainnet)

My provider doesn't seem out of sync block-wise (calling getBlockNumber on the provider returns what I expect), and like I said above, it works fine with similar constant function calls on other contracts.

For now, I'll use the human-readable ABI, but wanted to add my issue on here.

[treeder]

I'm not sure if this is related, but it sounds like it's got something to do with it and hopefully it will help someone else that has the same issue.

If I use this in my human readable abi it does NOT work and I get the call revert exception like OP:

"function tokenURI(uint256) view returns (string)",

If I change it to uint, it works.

"function tokenURI(uint) view returns (string)",

[ricmoo]

@treeder Can you provide a transaction example where those two don't do the same thing? The 256 should be optional and not affect anything.

[ricmoo]

Is the OP still an issue? I'm moving it to discussions, but would love more feedback on the problem or if it has been resolved.

[MattCrBoom]

(