you're upgrading the repository from language version 1 to 2, version 2 adds new compiler errors that rejects some old code, or the library has removed some old deprecated API the repository was still using in some places—the key here being that it can't be something that needs to be completely atomic.
you have hundreds or thousands of files to fix. that is unreviewable as a single commit, but as a per-file, per-library, per-oncall, etc. commit it is not that bad.
you have hundreds or thousands of files to fix. that is unreviewable as a single commit, but as a per-file, per-library, per-oncall, etc. commit it is not that bad.