Re: Make COPY format extendable: Extract COPY TO format implementations

Hi,

In <CAKFQuwYF7VnYcS9dkfvdzt-dgftMB1DV0bjRcNC8-4iYGS+gjw@mail.gmail.com>
  "Re: Make COPY format extendable: Extract COPY TO format implementations" on Sat, 29 Mar 2025 09:48:22 -0700,
  "David G. Johnston" <david.g.johnston@gmail.com> wrote:

> I don't think this module should be responsible for testing the validity of
> "qualified names in a string literal" behavior.  Having some of the tests
> use a schema qualification, and I'd suggest explicit
> double-quoting/case-folding, wouldn't hurt just to demonstrate it's
> possible, and how extensions should be referenced, but definitely don't
> need tests to prove the broken cases are indeed broken.  This relies on an
> existing API that has its own tests.  It is definitely pointlessly
> redundant to have 6 tests that only differ from 6 other tests in their use
> of a schema qualification.

You suggest the followings, right?

1. Add tests for "Schema.Name" with mixed cases
2. Remove the following 6 tests in
   src/test/modules/test_copy_format/sql/invalid.sql

   ----
   COPY public.test FROM stdin WITH (FORMAT 'test_schema.test_copy_format_wrong_input_type');
   COPY public.test TO stdout WITH (FORMAT 'test_schema.test_copy_format_wrong_input_type');
   COPY public.test FROM stdin WITH (FORMAT 'test_schema.test_copy_format_wrong_return_type');
   COPY public.test TO stdout WITH (FORMAT 'test_schema.test_copy_format_wrong_return_type');
   COPY public.test FROM stdin WITH (FORMAT 'test_schema.test_copy_format_wrong_return_value');
   COPY public.test TO stdout WITH (FORMAT 'test_schema.test_copy_format_wrong_return_value');
   ----

   because we have the following 6 tests:

   ----
   SET search_path = public,test_schema;
   COPY public.test FROM stdin WITH (FORMAT 'test_copy_format_wrong_input_type');
   COPY public.test TO stdout WITH (FORMAT 'test_copy_format_wrong_input_type');
   COPY public.test FROM stdin WITH (FORMAT 'test_copy_format_wrong_return_type');
   COPY public.test TO stdout WITH (FORMAT 'test_copy_format_wrong_return_type');
   COPY public.test FROM stdin WITH (FORMAT 'test_copy_format_wrong_return_value');
   COPY public.test TO stdout WITH (FORMAT 'test_copy_format_wrong_return_value');
   RESET search_path;
   ----
3. Remove the following tests because the behavior must be
   tested in other places:

   ----
   COPY public.test FROM stdin WITH (FORMAT 'nonexistent');
   COPY public.test TO stdout WITH (FORMAT 'nonexistent');
   COPY public.test FROM stdin WITH (FORMAT 'invalid.qualified.name');
   COPY public.test TO stdout WITH (FORMAT 'invalid.qualified.name');
   ----

Does it miss something?


1.: There is no difference between single-quoting and
    double-quoting here. Because the information what quote
    was used for the given FORMAT value isn't remained
    here. Should we update gram.y?

2.: I don't have a strong opinion for it. If nobody objects
    it, I'll remove them.

3.: I don't have a strong opinion for it. If nobody objects
    it, I'll remove them.


Thanks,
-- 
kou