Unpredictable gas limit error when sending transaction (in documentation example)

Hi. I’m following the “connecting to the DAI contract” code on the getting started documentation, and I keep on getting an unpredictable gas limit error.

For reference, here’s my code:

async function interact() {
  // https://docs.ethers.io/v5/getting-started/#getting-started--contracts
  const daiAddress = "dai.tokens.ethers.eth";

  const daiAbi = [
    // Some details about the token
    "function name() view returns (string)",
    "function symbol() view returns (string)",

    // Get the account balance
    "function balanceOf(address) view returns (uint)",

    // Send some of your tokens to someone else
    "function transfer(address to, uint amount)",

    // An event triggered whenever anyone transfers to someone else
    "event Transfer(address indexed from, address indexed to, uint amount)"
  ];

  const provider = ethers.getDefaultProvider(process.env.NETWORK);

  const wallet = new ethers.Wallet.fromMnemonic(process.env.METAMASK_PRIVATE_KEY).connect(provider);

  const daiContract = new ethers.Contract(daiAddress, daiAbi, provider);
  let daiSymbol = await daiContract.symbol(); 
  console.log(daiSymbol);

  const erc20_rw = new ethers.Contract(daiAddress, daiAbi, wallet)

  // // Each DAI has 18 decimal places
  const dai = ethers.utils.parseUnits("1.0", 18);

  await erc20_rw.transfer('0x7a250d5630B4cF539739dF2C5dAcb4c659F2488D', dai);
}

And every time this runs I get the following error:

Error: cannot estimate gas; transaction may fail or may require manual gas limit (error={"reason":"cannot estimate gas; transaction may fail or may require manual gas limit","code":"UNPREDICTABLE_GAS_LIMIT","method":"estimateGas","transaction":{"from":"0xe586C7BE1Ab861B658Ff49849ea27b0aFe0D5782","gasPrice":{"type":"BigNumber","hex":"0x47868c0000"},"to":"0x6B175474E89094C44Da98b954EedeAC495271d0F","data":"0xa9059cbb0000000000000000000000007a250d5630b4cf539739df2c5dacb4c659f2488d0000000000000000000000000000000000000000000000000de0b6b3a7640000"}}, tx={"data":"0xa9059cbb0000000000000000000000007a250d5630b4cf539739df2c5dacb4c659f2488d0000000000000000000000000000000000000000000000000de0b6b3a7640000","to":{},"from":"0xe586C7BE1Ab861B658Ff49849ea27b0aFe0D5782","gasPrice":{},"nonce":{},"gasLimit":{},"chainId":{}}, code=UNPREDICTABLE_GAS_LIMIT, version=abstract-signer/5.0.14)
    at Logger.makeError (/Users/alex/Local/Million-Dollar-NFT/NFT-contracts/node_modules/@ethersproject/logger/src.ts/index.ts:205:28)
    at Logger.throwError (/Users/alex/Local/Million-Dollar-NFT/NFT-contracts/node_modules/@ethersproject/logger/src.ts/index.ts:217:20)
    at /Users/alex/Local/Million-Dollar-NFT/NFT-contracts/node_modules/@ethersproject/abstract-signer/src.ts/index.ts:213:31
    at processTicksAndRejections (internal/process/task_queues.js:97:5)
    at async Promise.all (index 5) {
  reason: 'cannot estimate gas; transaction may fail or may require manual gas limit',
  code: 'UNPREDICTABLE_GAS_LIMIT',
  error: Error: cannot estimate gas; transaction may fail or may require manual gas limit (method="estimateGas", transaction={"from":"0xe586C7BE1Ab861B658Ff49849ea27b0aFe0D5782","gasPrice":{"type":"BigNumber","hex":"0x47868c0000"},"to":"0x6B175474E89094C44Da98b954EedeAC495271d0F","data":"0xa9059cbb0000000000000000000000007a250d5630b4cf539739df2c5dacb4c659f2488d0000000000000000000000000000000000000000000000000de0b6b3a7640000"}, code=UNPREDICTABLE_GAS_LIMIT, version=providers/5.0.24)
      at Logger.makeError (/Users/alex/Local/Million-Dollar-NFT/NFT-contracts/node_modules/@ethersproject/logger/src.ts/index.ts:205:28)
      at Logger.throwError (/Users/alex/Local/Million-Dollar-NFT/NFT-contracts/node_modules/@ethersproject/logger/src.ts/index.ts:217:20)
      at /Users/alex/Local/Million-Dollar-NFT/NFT-contracts/node_modules/@ethersproject/providers/src.ts/fallback-provider.ts:631:24
      at Array.forEach (<anonymous>)
      at /Users/alex/Local/Million-Dollar-NFT/NFT-contracts/node_modules/@ethersproject/providers/src.ts/fallback-provider.ts:613:33
      at step (/Users/alex/Local/Million-Dollar-NFT/NFT-contracts/node_modules/@ethersproject/providers/lib/fallback-provider.js:48:23)
      at Object.next (/Users/alex/Local/Million-Dollar-NFT/NFT-contracts/node_modules/@ethersproject/providers/lib/fallback-provider.js:29:53)
      at step (/Users/alex/Local/Million-Dollar-NFT/NFT-contracts/node_modules/@ethersproject/providers/lib/fallback-provider.js:33:139)
      at Object.next (/Users/alex/Local/Million-Dollar-NFT/NFT-contracts/node_modules/@ethersproject/providers/lib/fallback-provider.js:29:53)
      at fulfilled (/Users/alex/Local/Million-Dollar-NFT/NFT-contracts/node_modules/@ethersproject/providers/lib/fallback-provider.js:20:58) {
    reason: 'cannot estimate gas; transaction may fail or may require manual gas limit',
    code: 'UNPREDICTABLE_GAS_LIMIT',
    method: 'estimateGas',
    transaction: {
      from: '0xe586C7BE1Ab861B658Ff49849ea27b0aFe0D5782',
      gasPrice: [BigNumber],
      to: '0x6B175474E89094C44Da98b954EedeAC495271d0F',
      data: '0xa9059cbb0000000000000000000000007a250d5630b4cf539739df2c5dacb4c659f2488d0000000000000000000000000000000000000000000000000de0b6b3a7640000'
    }
  },
  tx: {
    data: '0xa9059cbb0000000000000000000000007a250d5630b4cf539739df2c5dacb4c659f2488d0000000000000000000000000000000000000000000000000de0b6b3a7640000',
    to: Promise { '0x6B175474E89094C44Da98b954EedeAC495271d0F' },
    from: '0xe586C7BE1Ab861B658Ff49849ea27b0aFe0D5782',
    gasPrice: Promise { [BigNumber] },
    nonce: Promise { 0 },
    gasLimit: Promise { <rejected> [Circular] },
    chainId: Promise { 1 }
  }

How can I fix this?

[zemse]

await erc20_rw.transfer('0x7a250d5630B4cF539739dF2C5dAcb4c659F2488D', dai, {
  gasLimit: 1000000
});

For more docs you can visit here.

[hamishjohnson]

Overriding the gasLimit worked for me 😃 tyvm