I've re-written the set of tests as suggested (I hope!). I've not re-run the coverage report (yet) to ensure we're at least as well covered as v3, but attached is v4 for your inspection (amusement?). I've tried to author the SQL tests such that failures clearly indicate what's at gone wrong.
This exercise turned into a lot more LOC than I'd expected, I hope it provides some value to the community for testing this important data structure and helps to codify the API clearly. best. -greg
v4-0001-Add-a-module-that-tests-Bitmapset.patch
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