fetchIfDifferent returns differences: true 100% of the time for UUPS deployments

[stshort]

Describe the bug If you deploy a UUPS contract, the function fetchIfDifferent returns differences: true in the return object 100% of the time. This is because the transaction it uses to compare the transaction data seems to be the transaction which deployed the proxy contract, not the implementation contract. I would expect to be able to detect differences so I can write a proper skip function and utilize this helper, however because of this issue, it will report changes 100% of the time, regardless of whether contract data actually changed:

https://github.com/wighawag/hardhat-deploy/blob/master/src/helpers.ts#L973

This is the line the check fails at every time.

To Reproduce Steps to reproduce the behavior:

1. Create a UUPS contract deployment script
2. Specify a skip function that uses the fetchIfDifferent function to determine whether a deploy script should be skipped.
3. Deploy the proxy contract
4. Re-run the same deployment script. Notice that the skip function incorrectly determines there were changes, and will rerun the deployment.

Expected behavior If the actual implementation contract for a UUPS contract has changed, this should return differences: true. If no data has changed from the implementation contract, it should return differences: false.

This could be likely fixed by checking the deploy options to see if it is a proxy, and if so, use the transaction hash for the implementation contract instead of the proxy contract when fetching the contract data for this comparison.

versions

• hardhat-deploy 0.11.24
• hardhat 2.12.6
• nodejs lts

Additional context Add any other context about the problem here.