OK core tests in 1.10 with this because:

TestRowDelta > testCannotMergeDVsMismatchedSequenceNumbers() > formatVersion = 3, branch = main FAILED
    java.lang.IllegalArgumentException: Content offset is required for DV
        at org.apache.iceberg.relocated.com.google.common.base.Preconditions.checkArgument(Preconditions.java:141)
        at org.apache.iceberg.FileMetadata$Builder.build(FileMetadata.java:259)
        at org.apache.iceberg.TestRowDelta.testCannotMergeDVsMismatchedSequenceNumbers(TestRowDelta.java:2201)

that's a new test I added as part of the original change but the test relies on making sure DV fields are properly copied over in the FileMetadata builder copy(DeleteFile) api, and that was fixed in a PR #14351 . I think there's a good argument that we should backport #14351 first because that's simply a correctness problem in that API without that fix (I would expect copy to always preserve those fields as is) but I'm not sure if this will cause behavior changes in the backport release, will check that out further.

If not, then we just update this test in this 1.10 branch to just explicitly pass through the value in the builder

I would probably just modify/ remove the failing test to avoid the behavior change unless you are 100% confident we would really be always fixing a bug and not break anyone with slightly different behavior. We can always have folks upgrade to 11 if they need the check to work.

Yeah I agree @RussellSpitzer , I took another look and while we could cherry pick the specific parts of #14351 to address this bug, it's probably not worth it for a patch release where it's unclear if someone relies on the fields being nulled out or something after a copy. It's better to have that change be in 1.11. I updated the tests to work around the issue.

Thanks all, merging!