I agree with advice of code style, and I have trim trailing whitespace in V6 patch.
The v6 patch still has code format issue, and the v6 looks almost same to v5.
git am v6-0001-fix-group_by_has_partkey-bug-and-add-regress-test.patch Applying: fix-group_by_has_partkey-bug-and-add-regress-test .git/rebase-apply/patch:31: trailing whitespace. * Set collation in group by clause using COLLATE syntax, .git/rebase-apply/patch:41: trailing whitespace.