Ship some of the new Solidity panic codes as part of "@ethersproject/constants"

[PaulRBerg]

Since Solidity v0.8.0, a new invalid opcode is used instead of the revert opcode in certain cases (the compiler panics instead of reverting). Common cases include arithmetic overflow and underflow and division by zero.

The consequence for contract developers is that now we have to account for these panic codes in our tests. Thus I ended up defining them in a TypeScript enum:

https://github.com/hifi-finance/prb-math/blob/33d957a4dd56f63c8b098300d07a4e47ae376ded/packages/prb-math/test/shared/errors.ts

I think that these will become popular enough to deserve to be included in the @ethersproject/constants package.

[ricmoo]

I don't know if the constants makes the most sense to keep them in, but the Interface object already parses out Panic events, I should add the Panic reasons to Panic errors.

It probably won't make it into v5, but I'll add this in v6, so the Interface object will automatically add the extra property.

[PaulRBerg]

You mean the Interface object part of an instance of Contract?

[ricmoo]

Yes, it's its own package (@ethersproject/abi), which the Contract object uses. It currently detects Panic and includes Panic(uint256) as the signature and Panic as the name.

I'll add a field like panicReason when a Panic is triggered.

[ricmoo]

(the Contract class is a thin meta-class wrapping the concrete Interface object)