These were all revealed as small inconsistencies in things including the test dataset, by an experiment with using Hash::Merge for what is now _merge_schema, which as you're undoubtedly aware copies data rather than mutating it.
Coverage increased (+0.2%) to 100.0% when pulling d519660123652e9ba7e5828de9d229666b718cc9 on mohawk2:mutability-tweaks into a523e20b1e7103bb5db8e20db0c919465e31a345 on preaction:master.
These were all revealed as small inconsistencies in things including the test dataset, by an experiment with using
Hash::Merge
for what is now_merge_schema
, which as you're undoubtedly aware copies data rather than mutating it.