On Tue, Apr 13, 2021 at 8:59 AM Tom Lane <t...@sss.pgh.pa.us> wrote: > I am wondering what was the intent of this test case added by commit > 257836a75: > > CREATE INDEX icuidx16_mood ON collate_test(id) WHERE mood > 'ok' COLLATE > "fr-x-icu"; > > where "mood" is of an enum type, which surely does not respond to > collations. > > The reason I ask is that this case started failing after I fixed > a parse_coerce.c bug that allowed a CollateExpr node to survive > in this WHERE expression, which by rights it should not. I'm > inclined to think that the test case is wrong and should be removed, > but maybe there's some reason to have a variant of it.
Indeed, this doesn't do anything useful, other than prove that we record a collation dependency where it is (uselessly) allowed in an expression. Since you're not going to allow that anymore, it should be dropped.
