Bug in response-handling for post-processing on etherscan-provider

[MatsThijssen]

Ethers Version

6.7.1

Search Terms

json, unexpected token, <, SyntaxError

Describe the Problem

Error in post-processing function stemming from a syntax-error in JSON.parse() was thrown when calling broadcastTransaction on an EtherScan-provider. Not sure how to reproduce, have never seen this before.

I believe the error is associated with this line: https://github.com/ethers-io/ethers.js/blob/main/src.ts/providers/provider-etherscan.ts#L258 where I guess the response is not properly sanitized for some specific cases, though I am not 100% sure what happened here.

What makes the error quite severe is that the transaction was still broadcast onto the network, which is obviously unexpected if the function throws.

Code Snippet

No response

Contract ABI

No response

Errors

Error: error in post-processing function (request={  }, response={  }, error={  }, code=SERVER_ERROR, version=6.7.1)
    at makeError (/home/node/node_modules/ethers/lib.commonjs/utils/errors.js:125:21)
    at assert (/home/node/node_modules/ethers/lib.commonjs/utils/errors.js:142:15)
    at FetchResponse.assertOk (/home/node/node_modules/ethers/lib.commonjs/utils/fetch.js:789:32)
    at #send (/home/node/node_modules/ethers/lib.commonjs/utils/fetch.js:470:90)
    at process.processTicksAndRejections (node:internal/process/task_queues:95:5)
    at async EtherscanProvider.fetch (/home/node/node_modules/ethers/lib.commonjs/providers/provider-etherscan.js:203:26)
    at async #perform (/home/node/node_modules/ethers/lib.commonjs/providers/abstract-provider.js:265:16)
    at async EtherscanProvider.getBlockNumber (/home/node/node_modules/ethers/lib.commonjs/providers/abstract-provider.js:373:55)
    at async Promise.all (index 0)
    at async resolveProperties (/home/node/node_modules/ethers/lib.commonjs/utils/properties.js:36:21)

Environment

node.js (v12 or newer)

Environment (Other)

No response