fix(ctb): N-03 Assert for impossible condition

[maurelian]

Description

Uses assert rather than a require statements to check for conditions we believe are unreachable.

This is more semantically explicit, and should enable us to more effectively use some advanced analysis methods in our testing.

IMO it's also more readable.

Tests

We don't have a good harness in place for verifying that code is unreachable. Making use of Solidity's SMTChecker would be good to do eventually.

[changeset-bot]

🦋 Changeset detected

Latest commit: f873a73

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 5 packages

Name	Type
@eth-optimism/contracts-bedrock	Patch
@eth-optimism/actor-tests	Patch
@eth-optimism/sdk	Patch
@eth-optimism/drippie-mon	Patch
@eth-optimism/message-relayer	Patch

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[tynes]

100% on getting the SMT checker going. Do you know of anything better than the solidity docs for an intro on getting going with it?

[maurelian]

This looks interesting, though not directly useful without installing dapp: https://fv.ethereum.org/2021/12/01/smtchecker-dapptools/

For what little I've used it in the past I've just referred to the official docs.

[mergify]

Hey @maurelian! This PR has merge conflicts. Please fix them before continuing review.

[tynes]

This looks like it needs a rebase before merge, but the code looks good to me

[mergify]

This PR has been added to the merge queue, and will be merged soon.

[mergify]

This PR is next in line to be merged, and will be merged as soon as checks pass.