Constitutional Committee Ratification

[teodanciu]

Description

Adds constitutional committee ratification as a mandatory check in Ratify.
Closes #3701
Closes #3444

The structure of the code is very similar to drep` ratification, so we could abstract it.

Missing:

• Fix ConwayFeatures test EDIT: Fixed
• voting no when the committee is too small (CC vote always No, when the committee is too small #3444)
• there is a contradiction between a comment on the issue and (what I think I see in ) the spec EDIT: clarified

  This means that expired and resigned committee members still contribute to the ratio calculation, despite that their votes do not count.

• some unseemly duplication in the test, should find a better way to set expired or resigned members with less noise EDIT: refactored to remove the duplication!

Might be just a problem of semantics, but in this PR, I wouldn't say that expired and resigned "contribute to the ratio" (unless we interpret that as: because they're expired or resigned we don't count them at all..)

Checklist

• Commit sequence broadly makes sense and commits have useful messages
• New tests are added if needed and existing tests are updated
• When applicable, versions are updated in .cabal and CHANGELOG.md files according to the
  versioning process.
• The version bounds in .cabal files for all affected packages are updated. If you change the bounds in a cabal file, that package itself must have a version increase. (See RELEASING.md)
• All visible changes are prepended to the latest section of a CHANGELOG.md for the affected packages. New section is never added with the code changes. (See RELEASING.md)
• Code is formatted with fourmolu (use scripts/fourmolize.sh)
• Cabal files are formatted (use scripts/cabal-format.sh)
• hie.yaml has been updated (use scripts/gen-hie.sh)
• Self-reviewed the diff

[lehins]

there is a contradiction betweenhttps://github.com//issues/3701#issuecomment-1706790738 and (what I think I see in ) the spec:

Yeah, that comment on the ticket was wrong. I've fixed it. All expired and resigned CC members are considered as if they abstained:

https://github.com/input-output-hk/formal-ledger-specifications/blob/5feb58cd4f43aa331748503a2bfc9d2a04a1f015/src/Ledger/Ratify.lagda#L258-L261

[lehins]

Majority of my comments are about how the test suite can be improved.

From what I can see nothing is blocking this PR from being merged.

Great work!!!

[lehins]

Spoke too soon 😁

Latest changes made it wrong After looking a bit closer, they are actually fine.

[lehins]

Looks great. Thank you for doing this work!