Re: psql: tab-completion support for COPY ... TO/FROM STDIN, STDOUT, and PROGRAM - Mailing list pgsql-hackers

On Mon, Dec 22, 2025 at 7:37 AM Yugo Nagata <nagata@sraoss.co.jp> wrote:
>
> On Mon, 24 Nov 2025 15:32:36 -0800
> Masahiko Sawada <sawada.mshk@gmail.com> wrote:
>
> I'm sorry for the late response.
>
> > Thank you for updating the patch! I have one question about the
> > following change:
> >
> > +   /* Complete COPY <sth> FROM|TO [PROGRAM] filename WITH ( */
> > +   else if (HeadMatches("COPY|\\copy", MatchAny, "FROM|TO",
> > MatchAnyExcept("PROGRAM"), "WITH", "(") ||
> > +            HeadMatches("COPY|\\copy", MatchAny, "FROM|TO",
> > "PROGRAM", MatchAny, "WITH", "("))
> > +   {
> > +       if (!HeadMatches("COPY|\\copy", MatchAny, "FROM|TO",
> > MatchAnyExcept("PROGRAM"), "WITH", "(*)") &&
> > +           !HeadMatches("COPY|\\copy", MatchAny, "FROM|TO",
> > "PROGRAM", MatchAny, "WITH", "(*)"))
> > +       {
> >
> > Given get_previous_words() treats a completed parenthesized option
> > list as one word, why is the later if statement necessary? In the
> > situation where the condition of the later if statement becomes false,
> > the condition of the first 'else if' statement should have become
> > false, no?
>
> First of all, the condition of the outer 'else if' was wrong.
> What I actually meant was:
>
>  +   /* Complete COPY <sth> FROM|TO [PROGRAM] filename WITH ( */
>  +   else if (HeadMatches("COPY|\\copy", MatchAny, "FROM|TO",
> MatchAnyExcept("PROGRAM"), "WITH", "(*") ||
>  +            HeadMatches("COPY|\\copy", MatchAny, "FROM|TO",
>  "PROGRAM", MatchAny, "WITH", "(*"))
>
> That is, the last word should be "(*" instead of "(".
> I've attached an updated patch reflecting this fix.
>
> This patterm is mimic how option lists are handled in the other places.
> For example:
>
> 3160     else if (HeadMatches("ANALYZE", "(*") &&
> 3161              !HeadMatches("ANALYZE", "(*)"))
>
> This prevents option completion after a completed paranthesized option list.
> For example, after "ANALYZE (VERVOSE ON) tbl (", no ANALYZE options are suggested,
> instead column names of the table "tbl" are suggested.
>
> Similarly, this change prevents completion of COPY options after
> "COPY tbl FROM stdin WITH ( FORMAT text ) WHERE (", for example.

Thank you for updating the patch and the explanation!

I agree with these changes, so I've pushed the patch. Also, this
commit fest item is now marked as 'Committed'.


Regards,

--
Masahiko Sawada
Amazon Web Services: https://aws.amazon.com