cardano-testnet: Avoid rewrite of sgMaxLovelaceSupply

[smelc]

Description

Avoid this hacky rewrite that was necessary for the treasury growth test to pass (without the rewrite the treasury was negative).

How to trust this PR

The treasury growth test now passes without the genesis' rewrite (try it with PARALLEL_TESTNETS=1 DISABLE_RETRIES=1 cabal test cardano-testnet-test --test-options '-p "/Treasury Growth/"')

Checklist

• Commit sequence broadly makes sense and commits have useful messages
• CI passes. See note on CI.
• Self-reviewed the diff

[Jimbo4350]

So we are overwriting the inputGenesisShelleyFp. We don't want to do this.

[Jimbo4350]

It would be better to either:

• Disallow values that result in a negative treasury
• Add a check that will fail if the treasury in the node state is negative

We don't to hard code values unless its specifically contained in a default Haskell value

[smelc]

@Jimbo4350> Please note that this was the case before this PR, I'm not changing this behavior here 🙂

Disallow values that result in a negative treasury

Add a check that will fail if the treasury in the node state is negative

That was actually my first instinct, but alas, looking at the ledger's spec; it seems quite involved to catch cases that will cause treasury to be negative (at least with my level of knowledge) and also it seemed wrong to have this code here. I would favor reusing the ledger's core that does this (if any).

We don't to hard code values unless its specifically contained in a default Haskell value

Agreed, but I would rather do that in a follow-up PR. This PR is an improvement over the current state, so it makes sense as a first step.

[Jimbo4350]

Please note that this was the case before this PR, I'm not changing this behavior here

Yep definitely wasn't blaming you. It was likely me who put those values there 🤡

Agreed, but I would rather do that in a follow-up PR.

👍