Обсуждение: psql: tab-completion support for COPY ... TO/FROM STDIN, STDOUT, and PROGRAM

Hi,

Currently, tab completion for COPY only suggests filenames after TO or
FROM, even though STDIN, STDOUT, and PROGRAM are also valid syntax options.

I'd like to propose improving the tab completion behavior as described in
the subject, so that these keywords are suggested appropriately, and filenames
are offered as potential command names after the PROGRAM keyword.

I've attached this proposal as a patch series with the following three parts:


0001: Refactor match_previous_words() to remove direct use of rl_completion_matches()

This is a preparatory cleanup. Most completions in match_previous_words() already use 
COMPLETE_WITH* macros, which wrap rl_completion_matches(). However, some direct calls
still remain.

This patch replaces the remaining direct calls with COMPLETE_WITH_FILES or 
COMPLETE_WITH_GENERATOR, improving consistency and readability.

0002: Add tab completion support for COPY ... TO/FROM STDIN, STDOUT, and PROGRAM

This is the main patch. It extends tab completion to suggest STDIN, STDOUT, and PROGRAM
after TO or FROM. After PROGRAM, filenames are suggested as possible command names.

To support this, a new macro COMPLETE_WITH_FILES_PLUS is introduced. This allows
combining literal keywords with filename suggestions in the completion list.

0003: Improve tab completion for COPY option lists

Currently, only the first option in a parenthesized list is suggested during completion,
and nothing is suggested after a comma.

This patch enables suggestions after each comma, improving usability when specifying
multiple options.

Although not directly related to the main proposal, I believe this is a helpful enhancement
to COPY tab completion and included it here for completeness.

I’d appreciate your review and feedback on this series.


Best regards,
Yugo Nagata

-- 
Yugo Nagata <nagata@sraoss.co.jp>

On Thu, 5 Jun 2025 10:08:35 +0900
Yugo Nagata <nagata@sraoss.co.jp> wrote:

> Hi,
> 
> Currently, tab completion for COPY only suggests filenames after TO or
> FROM, even though STDIN, STDOUT, and PROGRAM are also valid syntax options.
> 
> I'd like to propose improving the tab completion behavior as described in
> the subject, so that these keywords are suggested appropriately, and filenames
> are offered as potential command names after the PROGRAM keyword.
> 
> I've attached this proposal as a patch series with the following three parts:

I'm sorry but the previous patches were accidentally broken and didn't work.
I've attached fixed patches. 
 
> 
> 0001: Refactor match_previous_words() to remove direct use of rl_completion_matches()
> 
> This is a preparatory cleanup. Most completions in match_previous_words() already use 
> COMPLETE_WITH* macros, which wrap rl_completion_matches(). However, some direct calls
> still remain.
> 
> This patch replaces the remaining direct calls with COMPLETE_WITH_FILES or 
> COMPLETE_WITH_GENERATOR, improving consistency and readability.
> 
> 0002: Add tab completion support for COPY ... TO/FROM STDIN, STDOUT, and PROGRAM
> 
> This is the main patch. It extends tab completion to suggest STDIN, STDOUT, and PROGRAM
> after TO or FROM. After PROGRAM, filenames are suggested as possible command names.
> 
> To support this, a new macro COMPLETE_WITH_FILES_PLUS is introduced. This allows
> combining literal keywords with filename suggestions in the completion list.
> 
> 0003: Improve tab completion for COPY option lists
> 
> Currently, only the first option in a parenthesized list is suggested during completion,
> and nothing is suggested after a comma.
> 
> This patch enables suggestions after each comma, improving usability when specifying
> multiple options.
> 
> Although not directly related to the main proposal, I believe this is a helpful enhancement
> to COPY tab completion and included it here for completeness.
> 
> I’d appreciate your review and feedback on this series.
> 
> 
> Best regards,
> Yugo Nagata
> 
> -- 
> Yugo Nagata <nagata@sraoss.co.jp>


-- 
Yugo Nagata <nagata@sraoss.co.jp>

On Thu, 5 Jun 2025 16:52:00 +0900
Yugo Nagata <nagata@sraoss.co.jp> wrote:

> On Thu, 5 Jun 2025 10:08:35 +0900
> Yugo Nagata <nagata@sraoss.co.jp> wrote:
> 
> > Hi,
> > 
> > Currently, tab completion for COPY only suggests filenames after TO or
> > FROM, even though STDIN, STDOUT, and PROGRAM are also valid syntax options.
> > 
> > I'd like to propose improving the tab completion behavior as described in
> > the subject, so that these keywords are suggested appropriately, and filenames
> > are offered as potential command names after the PROGRAM keyword.
> > 
> > I've attached this proposal as a patch series with the following three parts:
> 
> I'm sorry but the previous patches were accidentally broken and didn't work.
> I've attached fixed patches. 
>  
> > 
> > 0001: Refactor match_previous_words() to remove direct use of rl_completion_matches()
> > 
> > This is a preparatory cleanup. Most completions in match_previous_words() already use 
> > COMPLETE_WITH* macros, which wrap rl_completion_matches(). However, some direct calls
> > still remain.
> > 
> > This patch replaces the remaining direct calls with COMPLETE_WITH_FILES or 
> > COMPLETE_WITH_GENERATOR, improving consistency and readability.
> > 
> > 0002: Add tab completion support for COPY ... TO/FROM STDIN, STDOUT, and PROGRAM
> > 
> > This is the main patch. It extends tab completion to suggest STDIN, STDOUT, and PROGRAM
> > after TO or FROM. After PROGRAM, filenames are suggested as possible command names.
> > 
> > To support this, a new macro COMPLETE_WITH_FILES_PLUS is introduced. This allows
> > combining literal keywords with filename suggestions in the completion list.
> > 
> > 0003: Improve tab completion for COPY option lists
> > 
> > Currently, only the first option in a parenthesized list is suggested during completion,
> > and nothing is suggested after a comma.
> > 
> > This patch enables suggestions after each comma, improving usability when specifying
> > multiple options.
> > 
> > Although not directly related to the main proposal, I believe this is a helpful enhancement
> > to COPY tab completion and included it here for completeness.
> > 
> > I’d appreciate your review and feedback on this series.


I've attached rebased patches.

Best regards,
Yugo Nagata


-- 
Yugo Nagata <nagata@sraoss.co.jp>

On Tue, 17 Jun 2025 00:08:32 +0900
Yugo Nagata <nagata@sraoss.co.jp> wrote:

> On Thu, 5 Jun 2025 16:52:00 +0900
> Yugo Nagata <nagata@sraoss.co.jp> wrote:
> 
> > On Thu, 5 Jun 2025 10:08:35 +0900
> > Yugo Nagata <nagata@sraoss.co.jp> wrote:
> > 
> > > Hi,
> > > 
> > > Currently, tab completion for COPY only suggests filenames after TO or
> > > FROM, even though STDIN, STDOUT, and PROGRAM are also valid syntax options.
> > > 
> > > I'd like to propose improving the tab completion behavior as described in
> > > the subject, so that these keywords are suggested appropriately, and filenames
> > > are offered as potential command names after the PROGRAM keyword.
> > > 
> > > I've attached this proposal as a patch series with the following three parts:
> > 
> > I'm sorry but the previous patches were accidentally broken and didn't work.
> > I've attached fixed patches. 
> >  
> > > 
> > > 0001: Refactor match_previous_words() to remove direct use of rl_completion_matches()
> > > 
> > > This is a preparatory cleanup. Most completions in match_previous_words() already use 
> > > COMPLETE_WITH* macros, which wrap rl_completion_matches(). However, some direct calls
> > > still remain.
> > > 
> > > This patch replaces the remaining direct calls with COMPLETE_WITH_FILES or 
> > > COMPLETE_WITH_GENERATOR, improving consistency and readability.
> > > 
> > > 0002: Add tab completion support for COPY ... TO/FROM STDIN, STDOUT, and PROGRAM
> > > 
> > > This is the main patch. It extends tab completion to suggest STDIN, STDOUT, and PROGRAM
> > > after TO or FROM. After PROGRAM, filenames are suggested as possible command names.
> > > 
> > > To support this, a new macro COMPLETE_WITH_FILES_PLUS is introduced. This allows
> > > combining literal keywords with filename suggestions in the completion list.
> > > 
> > > 0003: Improve tab completion for COPY option lists
> > > 
> > > Currently, only the first option in a parenthesized list is suggested during completion,
> > > and nothing is suggested after a comma.
> > > 
> > > This patch enables suggestions after each comma, improving usability when specifying
> > > multiple options.
> > > 
> > > Although not directly related to the main proposal, I believe this is a helpful enhancement
> > > to COPY tab completion and included it here for completeness.
> > > 
> > > I’d appreciate your review and feedback on this series.

I've attached rebased patches.

Regards,
Yugo Nagata

-- 
Yugo Nagata <nagata@sraoss.co.jp>

On Thu, 17 Jul 2025 10:57:36 +0900
Yugo Nagata <nagata@sraoss.co.jp> wrote:

> On Tue, 17 Jun 2025 00:08:32 +0900
> Yugo Nagata <nagata@sraoss.co.jp> wrote:
> 
> > On Thu, 5 Jun 2025 16:52:00 +0900
> > Yugo Nagata <nagata@sraoss.co.jp> wrote:
> > 
> > > On Thu, 5 Jun 2025 10:08:35 +0900
> > > Yugo Nagata <nagata@sraoss.co.jp> wrote:
> > > 
> > > > Hi,
> > > > 
> > > > Currently, tab completion for COPY only suggests filenames after TO or
> > > > FROM, even though STDIN, STDOUT, and PROGRAM are also valid syntax options.
> > > > 
> > > > I'd like to propose improving the tab completion behavior as described in
> > > > the subject, so that these keywords are suggested appropriately, and filenames
> > > > are offered as potential command names after the PROGRAM keyword.
> > > > 
> > > > I've attached this proposal as a patch series with the following three parts:
> > > 
> > > I'm sorry but the previous patches were accidentally broken and didn't work.
> > > I've attached fixed patches. 
> > >  
> > > > 
> > > > 0001: Refactor match_previous_words() to remove direct use of rl_completion_matches()
> > > > 
> > > > This is a preparatory cleanup. Most completions in match_previous_words() already use 
> > > > COMPLETE_WITH* macros, which wrap rl_completion_matches(). However, some direct calls
> > > > still remain.
> > > > 
> > > > This patch replaces the remaining direct calls with COMPLETE_WITH_FILES or 
> > > > COMPLETE_WITH_GENERATOR, improving consistency and readability.
> > > > 
> > > > 0002: Add tab completion support for COPY ... TO/FROM STDIN, STDOUT, and PROGRAM
> > > > 
> > > > This is the main patch. It extends tab completion to suggest STDIN, STDOUT, and PROGRAM
> > > > after TO or FROM. After PROGRAM, filenames are suggested as possible command names.
> > > > 
> > > > To support this, a new macro COMPLETE_WITH_FILES_PLUS is introduced. This allows
> > > > combining literal keywords with filename suggestions in the completion list.
> > > > 
> > > > 0003: Improve tab completion for COPY option lists
> > > > 
> > > > Currently, only the first option in a parenthesized list is suggested during completion,
> > > > and nothing is suggested after a comma.
> > > > 
> > > > This patch enables suggestions after each comma, improving usability when specifying
> > > > multiple options.
> > > > 
> > > > Although not directly related to the main proposal, I believe this is a helpful enhancement
> > > > to COPY tab completion and included it here for completeness.
> > > > 
> > > > I’d appreciate your review and feedback on this series.

The previous patch was broken failed to complie since I missed following
the required format of if-conditions in match_previous_words().
I've attached update patches.

Regards,
Yugo Nagata

-- 
Yugo Nagata <nagata@sraoss.co.jp>

On Fri, 18 Jul 2025 at 12:49, Yugo Nagata <nagata@sraoss.co.jp> wrote:
>
> On Thu, 17 Jul 2025 10:57:36 +0900
> Yugo Nagata <nagata@sraoss.co.jp> wrote:
>
> > On Tue, 17 Jun 2025 00:08:32 +0900
> > Yugo Nagata <nagata@sraoss.co.jp> wrote:
> >
> > > On Thu, 5 Jun 2025 16:52:00 +0900
> > > Yugo Nagata <nagata@sraoss.co.jp> wrote:
> > >
> > > > On Thu, 5 Jun 2025 10:08:35 +0900
> > > > Yugo Nagata <nagata@sraoss.co.jp> wrote:
> > > >
> > > > > Hi,
> > > > >
> > > > > Currently, tab completion for COPY only suggests filenames after TO or
> > > > > FROM, even though STDIN, STDOUT, and PROGRAM are also valid syntax options.
> > > > >
> > > > > I'd like to propose improving the tab completion behavior as described in
> > > > > the subject, so that these keywords are suggested appropriately, and filenames
> > > > > are offered as potential command names after the PROGRAM keyword.
> > > > >
> > > > > I've attached this proposal as a patch series with the following three parts:
> > > >
> > > > I'm sorry but the previous patches were accidentally broken and didn't work.
> > > > I've attached fixed patches.
> > > >
> > > > >
> > > > > 0001: Refactor match_previous_words() to remove direct use of rl_completion_matches()
> > > > >
> > > > > This is a preparatory cleanup. Most completions in match_previous_words() already use
> > > > > COMPLETE_WITH* macros, which wrap rl_completion_matches(). However, some direct calls
> > > > > still remain.
> > > > >
> > > > > This patch replaces the remaining direct calls with COMPLETE_WITH_FILES or
> > > > > COMPLETE_WITH_GENERATOR, improving consistency and readability.
> > > > >
> > > > > 0002: Add tab completion support for COPY ... TO/FROM STDIN, STDOUT, and PROGRAM
> > > > >
> > > > > This is the main patch. It extends tab completion to suggest STDIN, STDOUT, and PROGRAM
> > > > > after TO or FROM. After PROGRAM, filenames are suggested as possible command names.
> > > > >
> > > > > To support this, a new macro COMPLETE_WITH_FILES_PLUS is introduced. This allows
> > > > > combining literal keywords with filename suggestions in the completion list.
> > > > >
> > > > > 0003: Improve tab completion for COPY option lists
> > > > >
> > > > > Currently, only the first option in a parenthesized list is suggested during completion,
> > > > > and nothing is suggested after a comma.
> > > > >
> > > > > This patch enables suggestions after each comma, improving usability when specifying
> > > > > multiple options.
> > > > >
> > > > > Although not directly related to the main proposal, I believe this is a helpful enhancement
> > > > > to COPY tab completion and included it here for completeness.
> > > > >
> > > > > I’d appreciate your review and feedback on this series.
>
> The previous patch was broken failed to complie since I missed following
> the required format of if-conditions in match_previous_words().
> I've attached update patches.
>
> Regards,
> Yugo Nagata
>
> --
> Yugo Nagata <nagata@sraoss.co.jp>

Hi! This tab completion support is indeed very useful. Thanks for
working on this.
I spotted potential improvement here: current v5 does not support COPY
completion for a pattern I do frequently use:
specifying COPY options without WITH clause e.g. "copy yy from
'/home/reshke/cpg/csv.csv' <tab>" Is not completed with BINARY, CSV,
DELIMITER etc.

--
Best regards,
Kirill Reshke

Hi

> > > > > > Currently, tab completion for COPY only suggests filenames after TO or
> > > > > > FROM, even though STDIN, STDOUT, and PROGRAM are also valid syntax options.
> > > > > >
> > > > > > I'd like to propose improving the tab completion behavior as described in
> > > > > > the subject, so that these keywords are suggested appropriately, and filenames
> > > > > > are offered as potential command names after the PROGRAM keyword.
> > > > > >
> > > > > > I've attached this proposal as a patch series with the following three parts:
> > > > >
> > > > > I'm sorry but the previous patches were accidentally broken and didn't work.
> > > > > I've attached fixed patches.
> > > > >
> > > > > >
> > > > > > 0001: Refactor match_previous_words() to remove direct use of rl_completion_matches()
> > > > > >
> > > > > > This is a preparatory cleanup. Most completions in match_previous_words() already use
> > > > > > COMPLETE_WITH* macros, which wrap rl_completion_matches(). However, some direct calls
> > > > > > still remain.
> > > > > >
> > > > > > This patch replaces the remaining direct calls with COMPLETE_WITH_FILES or
> > > > > > COMPLETE_WITH_GENERATOR, improving consistency and readability.
> > > > > >
> > > > > > 0002: Add tab completion support for COPY ... TO/FROM STDIN, STDOUT, and PROGRAM
> > > > > >
> > > > > > This is the main patch. It extends tab completion to suggest STDIN, STDOUT, and PROGRAM
> > > > > > after TO or FROM. After PROGRAM, filenames are suggested as possible command names.
> > > > > >
> > > > > > To support this, a new macro COMPLETE_WITH_FILES_PLUS is introduced. This allows
> > > > > > combining literal keywords with filename suggestions in the completion list.
> > > > > >
> > > > > > 0003: Improve tab completion for COPY option lists
> > > > > >
> > > > > > Currently, only the first option in a parenthesized list is suggested during completion,
> > > > > > and nothing is suggested after a comma.
> > > > > >
> > > > > > This patch enables suggestions after each comma, improving usability when specifying
> > > > > > multiple options.
> > > > > >
> > > > > > Although not directly related to the main proposal, I believe this is a helpful enhancement
> > > > > > to COPY tab completion and included it here for completeness.
> > > > > >
> > > > > > I’d appreciate your review and feedback on this series.

> Hi! This tab completion support is indeed very useful. Thanks for
> working on this.

Thank you for your feedback!

> I spotted potential improvement here: current v5 does not support COPY
> completion for a pattern I do frequently use:
> specifying COPY options without WITH clause e.g. "copy yy from
> '/home/reshke/cpg/csv.csv' <tab>" Is not completed with BINARY, CSV,
> DELIMITER etc.

This is the old syntax and is supported for backward compatibility 
(commit 923413ac6d3), but I’m not sure it’s worth supporting in tab
completion. Perhaps it would be better to discuss this point in a
separate thread.

Regards,
Yugo Nagata


-- 
Yugo Nagata <nagata@sraoss.co.jp>

On Thu, 28 Aug 2025 at 12:22, Yugo Nagata <nagata@sraoss.co.jp> wrote:
>
> > Hi! This tab completion support is indeed very useful. Thanks for
> > working on this.
>
> Thank you for your feedback!
>
> > I spotted potential improvement here: current v5 does not support COPY
> > completion for a pattern I do frequently use:
> > specifying COPY options without WITH clause e.g. "copy yy from
> > '/home/reshke/cpg/csv.csv' <tab>" Is not completed with BINARY, CSV,
> > DELIMITER etc.
>
> This is the old syntax and is supported for backward compatibility
> (commit 923413ac6d3), but I’m not sure it’s worth supporting in tab
> completion. Perhaps it would be better to discuss this point in a
> separate thread.
>

I see your point. However I do not think that old syntax is a show-stopper here.
current psql (on HEAD) has TAB support for archaic patterns like START
<tab> completed with TRANSACTION and ABORT W<tab> completed with WORK.
And I do think that the case I use in COPY (and propose to support
thus) is more frequent than these two. I came across this thread while
looking to support my usecase.
This does not make you obligated to support this in this patch series.
I can even send v5-0004 with this support in the thread if that's
okay.

--
Best regards,
Kirill Reshke

On Fri, Jul 18, 2025 at 12:49 AM Yugo Nagata <nagata@sraoss.co.jp> wrote:
>
> On Thu, 17 Jul 2025 10:57:36 +0900
> Yugo Nagata <nagata@sraoss.co.jp> wrote:
>
> > On Tue, 17 Jun 2025 00:08:32 +0900
> > Yugo Nagata <nagata@sraoss.co.jp> wrote:
> >
> > > On Thu, 5 Jun 2025 16:52:00 +0900
> > > Yugo Nagata <nagata@sraoss.co.jp> wrote:
> > >
> > > > On Thu, 5 Jun 2025 10:08:35 +0900
> > > > Yugo Nagata <nagata@sraoss.co.jp> wrote:
> > > >
> > > > > Hi,
> > > > >
> > > > > Currently, tab completion for COPY only suggests filenames after TO or
> > > > > FROM, even though STDIN, STDOUT, and PROGRAM are also valid syntax options.
> > > > >
> > > > > I'd like to propose improving the tab completion behavior as described in
> > > > > the subject, so that these keywords are suggested appropriately, and filenames
> > > > > are offered as potential command names after the PROGRAM keyword.
> > > > >
> > > > > I've attached this proposal as a patch series with the following three parts:
> > > >
> > > > I'm sorry but the previous patches were accidentally broken and didn't work.
> > > > I've attached fixed patches.
> > > >
> > > > >
> > > > > 0001: Refactor match_previous_words() to remove direct use of rl_completion_matches()
> > > > >
> > > > > This is a preparatory cleanup. Most completions in match_previous_words() already use
> > > > > COMPLETE_WITH* macros, which wrap rl_completion_matches(). However, some direct calls
> > > > > still remain.
> > > > >
> > > > > This patch replaces the remaining direct calls with COMPLETE_WITH_FILES or
> > > > > COMPLETE_WITH_GENERATOR, improving consistency and readability.
> > > > >
> > > > > 0002: Add tab completion support for COPY ... TO/FROM STDIN, STDOUT, and PROGRAM
> > > > >
> > > > > This is the main patch. It extends tab completion to suggest STDIN, STDOUT, and PROGRAM
> > > > > after TO or FROM. After PROGRAM, filenames are suggested as possible command names.
> > > > >
> > > > > To support this, a new macro COMPLETE_WITH_FILES_PLUS is introduced. This allows
> > > > > combining literal keywords with filename suggestions in the completion list.
> > > > >
> > > > > 0003: Improve tab completion for COPY option lists
> > > > >
> > > > > Currently, only the first option in a parenthesized list is suggested during completion,
> > > > > and nothing is suggested after a comma.
> > > > >
> > > > > This patch enables suggestions after each comma, improving usability when specifying
> > > > > multiple options.
> > > > >
> > > > > Although not directly related to the main proposal, I believe this is a helpful enhancement
> > > > > to COPY tab completion and included it here for completeness.
> > > > >
> > > > > I’d appreciate your review and feedback on this series.
>
> The previous patch was broken failed to complie since I missed following
> the required format of if-conditions in match_previous_words().
> I've attached update patches.
>

I agree with the basic direction of the patches. Here are some
comments on the first two patches:

v5-0001-Refactor-match_previous_words-to-remove-direct-us.patch:

---
+#define COMPLETE_WITH_GENERATOR(function) \
+   matches = rl_completion_matches(text, function)

I think it would be clearer if we use 'generator' or 'genfunc' instead
of 'function' as a macro argument.


v5-0002-Add-tab-completion-support-for-COPY-.-TO-FROM-STD.patch:

---
+        /* Complete COPY|\copy <sth> FROM|TO PROGRAM command */
+        else if (Matches("COPY|\\copy", MatchAny, "FROM|TO", "PROGRAM"))
+                COMPLETE_WITH_FILES("", HeadMatches("COPY"));  /*
COPY requires quoted filename */

Why does it complete the query with files names even after 'PROGRAM'?

---
+static char *
+_complete_from_files(const char *text, int state)
 {

 I think the comments of complete_from_files() should be moved to this
new function. For instance, the comments starts with:

* This function wraps rl_filename_completion_function() to strip quotes from
* the input before searching for matches and to quote any matches for which
* the consuming command will require it.

But complete_from_files() function no longer calls
rl_filename_completion_function().

---
-   /* Complete COPY <sth> FROM <sth> */
-   else if (Matches("COPY|\\copy", MatchAny, "FROM", MatchAny))
+   /* Complete COPY <sth> FROM [PROGRAM] <sth> */
+   else if (Matches("COPY|\\copy", MatchAny, "FROM",
MatchAnyExcept("PROGRAM")) ||
+            Matches("COPY|\\copy", MatchAny, "FROM", "PROGRAM", MatchAny))

I see this kind of conversion many places in the patch; convert one
condition with MatchAny into two conditions with
MatchAnyExcept("PROGRAM") and '"PROGRAM", MatchAny'. How about
simplifying it using MatchAnyN. For example,

else if (Matches("COPY|\\copy", MatchAny, "FROM", MatchAny, MatchAnyN))

Regards,

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

On Wed, 17 Sep 2025 12:53:10 -0700
Masahiko Sawada <sawada.mshk@gmail.com> wrote:

> On Fri, Jul 18, 2025 at 12:49 AM Yugo Nagata <nagata@sraoss.co.jp> wrote:
> >
> > On Thu, 17 Jul 2025 10:57:36 +0900
> > Yugo Nagata <nagata@sraoss.co.jp> wrote:
> >
> > > On Tue, 17 Jun 2025 00:08:32 +0900
> > > Yugo Nagata <nagata@sraoss.co.jp> wrote:
> > >
> > > > On Thu, 5 Jun 2025 16:52:00 +0900
> > > > Yugo Nagata <nagata@sraoss.co.jp> wrote:
> > > >
> > > > > On Thu, 5 Jun 2025 10:08:35 +0900
> > > > > Yugo Nagata <nagata@sraoss.co.jp> wrote:
> > > > >
> > > > > > Hi,
> > > > > >
> > > > > > Currently, tab completion for COPY only suggests filenames after TO or
> > > > > > FROM, even though STDIN, STDOUT, and PROGRAM are also valid syntax options.
> > > > > >
> > > > > > I'd like to propose improving the tab completion behavior as described in
> > > > > > the subject, so that these keywords are suggested appropriately, and filenames
> > > > > > are offered as potential command names after the PROGRAM keyword.
> > > > > >
> > > > > > I've attached this proposal as a patch series with the following three parts:
> > > > >
> > > > > I'm sorry but the previous patches were accidentally broken and didn't work.
> > > > > I've attached fixed patches.
> > > > >
> > > > > >
> > > > > > 0001: Refactor match_previous_words() to remove direct use of rl_completion_matches()
> > > > > >
> > > > > > This is a preparatory cleanup. Most completions in match_previous_words() already use
> > > > > > COMPLETE_WITH* macros, which wrap rl_completion_matches(). However, some direct calls
> > > > > > still remain.
> > > > > >
> > > > > > This patch replaces the remaining direct calls with COMPLETE_WITH_FILES or
> > > > > > COMPLETE_WITH_GENERATOR, improving consistency and readability.
> > > > > >
> > > > > > 0002: Add tab completion support for COPY ... TO/FROM STDIN, STDOUT, and PROGRAM
> > > > > >
> > > > > > This is the main patch. It extends tab completion to suggest STDIN, STDOUT, and PROGRAM
> > > > > > after TO or FROM. After PROGRAM, filenames are suggested as possible command names.
> > > > > >
> > > > > > To support this, a new macro COMPLETE_WITH_FILES_PLUS is introduced. This allows
> > > > > > combining literal keywords with filename suggestions in the completion list.
> > > > > >
> > > > > > 0003: Improve tab completion for COPY option lists
> > > > > >
> > > > > > Currently, only the first option in a parenthesized list is suggested during completion,
> > > > > > and nothing is suggested after a comma.
> > > > > >
> > > > > > This patch enables suggestions after each comma, improving usability when specifying
> > > > > > multiple options.
> > > > > >
> > > > > > Although not directly related to the main proposal, I believe this is a helpful enhancement
> > > > > > to COPY tab completion and included it here for completeness.
> > > > > >
> > > > > > I’d appreciate your review and feedback on this series.
> >
> > The previous patch was broken failed to complie since I missed following
> > the required format of if-conditions in match_previous_words().
> > I've attached update patches.
> >
> 
> I agree with the basic direction of the patches. Here are some
> comments on the first two patches:

Thank you for reviewing it.
I've attached an updated patch.

> 
> v5-0001-Refactor-match_previous_words-to-remove-direct-us.patch:
> 
> ---
> +#define COMPLETE_WITH_GENERATOR(function) \
> +   matches = rl_completion_matches(text, function)
> 
> I think it would be clearer if we use 'generator' or 'genfunc' instead
> of 'function' as a macro argument.

I fixed it to use 'generator'.

> 
> v5-0002-Add-tab-completion-support-for-COPY-.-TO-FROM-STD.patch:
> 
> ---
> +        /* Complete COPY|\copy <sth> FROM|TO PROGRAM command */
> +        else if (Matches("COPY|\\copy", MatchAny, "FROM|TO", "PROGRAM"))
> +                COMPLETE_WITH_FILES("", HeadMatches("COPY"));  /*
> COPY requires quoted filename */
> 
> Why does it complete the query with files names even after 'PROGRAM'?

Users can specify the command by giving a filename with an absolute or
relative path, so I think it makes sense to allow filename completion
after PROGRAM.

> ---
> +static char *
> +_complete_from_files(const char *text, int state)
>  {
> 
>  I think the comments of complete_from_files() should be moved to this
> new function. For instance, the comments starts with:
> 
> * This function wraps rl_filename_completion_function() to strip quotes from
> * the input before searching for matches and to quote any matches for which
> * the consuming command will require it.
> 
> But complete_from_files() function no longer calls
> rl_filename_completion_function().

I moved the comments to the top of _complete_from_files() and added a new
comment for complete_from_files() to describe that it is a wrapper of the
former.
 
> ---
> -   /* Complete COPY <sth> FROM <sth> */
> -   else if (Matches("COPY|\\copy", MatchAny, "FROM", MatchAny))
> +   /* Complete COPY <sth> FROM [PROGRAM] <sth> */
> +   else if (Matches("COPY|\\copy", MatchAny, "FROM",
> MatchAnyExcept("PROGRAM")) ||
> +            Matches("COPY|\\copy", MatchAny, "FROM", "PROGRAM", MatchAny))
> 
> I see this kind of conversion many places in the patch; convert one
> condition with MatchAny into two conditions with
> MatchAnyExcept("PROGRAM") and '"PROGRAM", MatchAny'. How about
> simplifying it using MatchAnyN. For example,
> 
> else if (Matches("COPY|\\copy", MatchAny, "FROM", MatchAny, MatchAnyN))

We could simplify this by using MatchAnyN, but doing so would cause "WITH ("
or "WHERE" to be suggested after "WITH (...)", even though that is not allowed
by the syntax. This could be misleading for users, so I wonder whether it is
worth adding a bit of complexity to prevent possible confusion.

Regards,
Yugo Nagata

-- 
Yugo Nagata <nagata@sraoss.co.jp>

On Thu, 18 Sep 2025 12:05:06 +0900
Yugo Nagata <nagata@sraoss.co.jp> wrote:

> On Wed, 17 Sep 2025 12:53:10 -0700
> Masahiko Sawada <sawada.mshk@gmail.com> wrote:
> 
> > On Fri, Jul 18, 2025 at 12:49 AM Yugo Nagata <nagata@sraoss.co.jp> wrote:
> > >
> > > On Thu, 17 Jul 2025 10:57:36 +0900
> > > Yugo Nagata <nagata@sraoss.co.jp> wrote:
> > >
> > > > On Tue, 17 Jun 2025 00:08:32 +0900
> > > > Yugo Nagata <nagata@sraoss.co.jp> wrote:
> > > >
> > > > > On Thu, 5 Jun 2025 16:52:00 +0900
> > > > > Yugo Nagata <nagata@sraoss.co.jp> wrote:
> > > > >
> > > > > > On Thu, 5 Jun 2025 10:08:35 +0900
> > > > > > Yugo Nagata <nagata@sraoss.co.jp> wrote:
> > > > > >
> > > > > > > Hi,
> > > > > > >
> > > > > > > Currently, tab completion for COPY only suggests filenames after TO or
> > > > > > > FROM, even though STDIN, STDOUT, and PROGRAM are also valid syntax options.
> > > > > > >
> > > > > > > I'd like to propose improving the tab completion behavior as described in
> > > > > > > the subject, so that these keywords are suggested appropriately, and filenames
> > > > > > > are offered as potential command names after the PROGRAM keyword.
> > > > > > >
> > > > > > > I've attached this proposal as a patch series with the following three parts:
> > > > > >
> > > > > > I'm sorry but the previous patches were accidentally broken and didn't work.
> > > > > > I've attached fixed patches.
> > > > > >
> > > > > > >
> > > > > > > 0001: Refactor match_previous_words() to remove direct use of rl_completion_matches()
> > > > > > >
> > > > > > > This is a preparatory cleanup. Most completions in match_previous_words() already use
> > > > > > > COMPLETE_WITH* macros, which wrap rl_completion_matches(). However, some direct calls
> > > > > > > still remain.
> > > > > > >
> > > > > > > This patch replaces the remaining direct calls with COMPLETE_WITH_FILES or
> > > > > > > COMPLETE_WITH_GENERATOR, improving consistency and readability.
> > > > > > >
> > > > > > > 0002: Add tab completion support for COPY ... TO/FROM STDIN, STDOUT, and PROGRAM
> > > > > > >
> > > > > > > This is the main patch. It extends tab completion to suggest STDIN, STDOUT, and PROGRAM
> > > > > > > after TO or FROM. After PROGRAM, filenames are suggested as possible command names.
> > > > > > >
> > > > > > > To support this, a new macro COMPLETE_WITH_FILES_PLUS is introduced. This allows
> > > > > > > combining literal keywords with filename suggestions in the completion list.
> > > > > > >
> > > > > > > 0003: Improve tab completion for COPY option lists
> > > > > > >
> > > > > > > Currently, only the first option in a parenthesized list is suggested during completion,
> > > > > > > and nothing is suggested after a comma.
> > > > > > >
> > > > > > > This patch enables suggestions after each comma, improving usability when specifying
> > > > > > > multiple options.
> > > > > > >
> > > > > > > Although not directly related to the main proposal, I believe this is a helpful enhancement
> > > > > > > to COPY tab completion and included it here for completeness.
> > > > > > >
> > > > > > > I’d appreciate your review and feedback on this series.
> > >
> > > The previous patch was broken failed to complie since I missed following
> > > the required format of if-conditions in match_previous_words().
> > > I've attached update patches.
> > >
> > 
> > I agree with the basic direction of the patches. Here are some
> > comments on the first two patches:
> 
> Thank you for reviewing it.
> I've attached an updated patch.
> 
> > 
> > v5-0001-Refactor-match_previous_words-to-remove-direct-us.patch:
> > 
> > ---
> > +#define COMPLETE_WITH_GENERATOR(function) \
> > +   matches = rl_completion_matches(text, function)
> > 
> > I think it would be clearer if we use 'generator' or 'genfunc' instead
> > of 'function' as a macro argument.
> 
> I fixed it to use 'generator'.
> 
> > 
> > v5-0002-Add-tab-completion-support-for-COPY-.-TO-FROM-STD.patch:
> > 
> > ---
> > +        /* Complete COPY|\copy <sth> FROM|TO PROGRAM command */
> > +        else if (Matches("COPY|\\copy", MatchAny, "FROM|TO", "PROGRAM"))
> > +                COMPLETE_WITH_FILES("", HeadMatches("COPY"));  /*
> > COPY requires quoted filename */
> > 
> > Why does it complete the query with files names even after 'PROGRAM'?
> 
> Users can specify the command by giving a filename with an absolute or
> relative path, so I think it makes sense to allow filename completion
> after PROGRAM.
> 
> > ---
> > +static char *
> > +_complete_from_files(const char *text, int state)
> >  {
> > 
> >  I think the comments of complete_from_files() should be moved to this
> > new function. For instance, the comments starts with:
> > 
> > * This function wraps rl_filename_completion_function() to strip quotes from
> > * the input before searching for matches and to quote any matches for which
> > * the consuming command will require it.
> > 
> > But complete_from_files() function no longer calls
> > rl_filename_completion_function().
> 
> I moved the comments to the top of _complete_from_files() and added a new
> comment for complete_from_files() to describe that it is a wrapper of the
> former.
>  
> > ---
> > -   /* Complete COPY <sth> FROM <sth> */
> > -   else if (Matches("COPY|\\copy", MatchAny, "FROM", MatchAny))
> > +   /* Complete COPY <sth> FROM [PROGRAM] <sth> */
> > +   else if (Matches("COPY|\\copy", MatchAny, "FROM",
> > MatchAnyExcept("PROGRAM")) ||
> > +            Matches("COPY|\\copy", MatchAny, "FROM", "PROGRAM", MatchAny))
> > 
> > I see this kind of conversion many places in the patch; convert one
> > condition with MatchAny into two conditions with
> > MatchAnyExcept("PROGRAM") and '"PROGRAM", MatchAny'. How about
> > simplifying it using MatchAnyN. For example,
> > 
> > else if (Matches("COPY|\\copy", MatchAny, "FROM", MatchAny, MatchAnyN))
> 
> We could simplify this by using MatchAnyN, but doing so would cause "WITH ("
> or "WHERE" to be suggested after "WITH (...)", even though that is not allowed
> by the syntax. This could be misleading for users, so I wonder whether it is
> worth adding a bit of complexity to prevent possible confusion.

There was a mistake in the previous statement: "WHERE" appearing after "WITH (...)"
is actually correct. However, this also results in "WITH" being suggested after
"WHERE", which is not permitted by the syntax.

Regards,
Yugo Nagata

-- 
Yugo Nagata <nagata@sraoss.co.jp>

On Wed, Sep 17, 2025 at 8:27 PM Yugo Nagata <nagata@sraoss.co.jp> wrote:
>
> On Thu, 18 Sep 2025 12:05:06 +0900
> Yugo Nagata <nagata@sraoss.co.jp> wrote:
>
> > On Wed, 17 Sep 2025 12:53:10 -0700
> > Masahiko Sawada <sawada.mshk@gmail.com> wrote:
> >
> > > On Fri, Jul 18, 2025 at 12:49 AM Yugo Nagata <nagata@sraoss.co.jp> wrote:
> > > >
> > > > On Thu, 17 Jul 2025 10:57:36 +0900
> > > > Yugo Nagata <nagata@sraoss.co.jp> wrote:
> > > >
> > > > > On Tue, 17 Jun 2025 00:08:32 +0900
> > > > > Yugo Nagata <nagata@sraoss.co.jp> wrote:
> > > > >
> > > > > > On Thu, 5 Jun 2025 16:52:00 +0900
> > > > > > Yugo Nagata <nagata@sraoss.co.jp> wrote:
> > > > > >
> > > > > > > On Thu, 5 Jun 2025 10:08:35 +0900
> > > > > > > Yugo Nagata <nagata@sraoss.co.jp> wrote:
> > > > > > >
> > > > > > > > Hi,
> > > > > > > >
> > > > > > > > Currently, tab completion for COPY only suggests filenames after TO or
> > > > > > > > FROM, even though STDIN, STDOUT, and PROGRAM are also valid syntax options.
> > > > > > > >
> > > > > > > > I'd like to propose improving the tab completion behavior as described in
> > > > > > > > the subject, so that these keywords are suggested appropriately, and filenames
> > > > > > > > are offered as potential command names after the PROGRAM keyword.
> > > > > > > >
> > > > > > > > I've attached this proposal as a patch series with the following three parts:
> > > > > > >
> > > > > > > I'm sorry but the previous patches were accidentally broken and didn't work.
> > > > > > > I've attached fixed patches.
> > > > > > >
> > > > > > > >
> > > > > > > > 0001: Refactor match_previous_words() to remove direct use of rl_completion_matches()
> > > > > > > >
> > > > > > > > This is a preparatory cleanup. Most completions in match_previous_words() already use
> > > > > > > > COMPLETE_WITH* macros, which wrap rl_completion_matches(). However, some direct calls
> > > > > > > > still remain.
> > > > > > > >
> > > > > > > > This patch replaces the remaining direct calls with COMPLETE_WITH_FILES or
> > > > > > > > COMPLETE_WITH_GENERATOR, improving consistency and readability.
> > > > > > > >
> > > > > > > > 0002: Add tab completion support for COPY ... TO/FROM STDIN, STDOUT, and PROGRAM
> > > > > > > >
> > > > > > > > This is the main patch. It extends tab completion to suggest STDIN, STDOUT, and PROGRAM
> > > > > > > > after TO or FROM. After PROGRAM, filenames are suggested as possible command names.
> > > > > > > >
> > > > > > > > To support this, a new macro COMPLETE_WITH_FILES_PLUS is introduced. This allows
> > > > > > > > combining literal keywords with filename suggestions in the completion list.
> > > > > > > >
> > > > > > > > 0003: Improve tab completion for COPY option lists
> > > > > > > >
> > > > > > > > Currently, only the first option in a parenthesized list is suggested during completion,
> > > > > > > > and nothing is suggested after a comma.
> > > > > > > >
> > > > > > > > This patch enables suggestions after each comma, improving usability when specifying
> > > > > > > > multiple options.
> > > > > > > >
> > > > > > > > Although not directly related to the main proposal, I believe this is a helpful enhancement
> > > > > > > > to COPY tab completion and included it here for completeness.
> > > > > > > >
> > > > > > > > I’d appreciate your review and feedback on this series.
> > > >
> > > > The previous patch was broken failed to complie since I missed following
> > > > the required format of if-conditions in match_previous_words().
> > > > I've attached update patches.
> > > >
> > >
> > > I agree with the basic direction of the patches. Here are some
> > > comments on the first two patches:
> >
> > Thank you for reviewing it.
> > I've attached an updated patch.

Thank you for updating the patches!

> >
> > >
> > > v5-0001-Refactor-match_previous_words-to-remove-direct-us.patch:
> > >
> > > ---
> > > +#define COMPLETE_WITH_GENERATOR(function) \
> > > +   matches = rl_completion_matches(text, function)
> > >
> > > I think it would be clearer if we use 'generator' or 'genfunc' instead
> > > of 'function' as a macro argument.
> >
> > I fixed it to use 'generator'.

LGTM. I've pushed the 0001 patch.

> >
> > >
> > > v5-0002-Add-tab-completion-support-for-COPY-.-TO-FROM-STD.patch:
> > >
> > > ---
> > > +        /* Complete COPY|\copy <sth> FROM|TO PROGRAM command */
> > > +        else if (Matches("COPY|\\copy", MatchAny, "FROM|TO", "PROGRAM"))
> > > +                COMPLETE_WITH_FILES("", HeadMatches("COPY"));  /*
> > > COPY requires quoted filename */
> > >
> > > Why does it complete the query with files names even after 'PROGRAM'?
> >
> > Users can specify the command by giving a filename with an absolute or
> > relative path, so I think it makes sense to allow filename completion
> > after PROGRAM.

Agreed.

> >
> > > ---
> > > +static char *
> > > +_complete_from_files(const char *text, int state)
> > >  {
> > >
> > >  I think the comments of complete_from_files() should be moved to this
> > > new function. For instance, the comments starts with:
> > >
> > > * This function wraps rl_filename_completion_function() to strip quotes from
> > > * the input before searching for matches and to quote any matches for which
> > > * the consuming command will require it.
> > >
> > > But complete_from_files() function no longer calls
> > > rl_filename_completion_function().
> >
> > I moved the comments to the top of _complete_from_files() and added a new
> > comment for complete_from_files() to describe that it is a wrapper of the
> > former.
> >
> > > ---
> > > -   /* Complete COPY <sth> FROM <sth> */
> > > -   else if (Matches("COPY|\\copy", MatchAny, "FROM", MatchAny))
> > > +   /* Complete COPY <sth> FROM [PROGRAM] <sth> */
> > > +   else if (Matches("COPY|\\copy", MatchAny, "FROM",
> > > MatchAnyExcept("PROGRAM")) ||
> > > +            Matches("COPY|\\copy", MatchAny, "FROM", "PROGRAM", MatchAny))
> > >
> > > I see this kind of conversion many places in the patch; convert one
> > > condition with MatchAny into two conditions with
> > > MatchAnyExcept("PROGRAM") and '"PROGRAM", MatchAny'. How about
> > > simplifying it using MatchAnyN. For example,
> > >
> > > else if (Matches("COPY|\\copy", MatchAny, "FROM", MatchAny, MatchAnyN))
> >
> > We could simplify this by using MatchAnyN, but doing so would cause "WITH ("
> > or "WHERE" to be suggested after "WITH (...)", even though that is not allowed
> > by the syntax. This could be misleading for users, so I wonder whether it is
> > worth adding a bit of complexity to prevent possible confusion.
>
> There was a mistake in the previous statement: "WHERE" appearing after "WITH (...)"
> is actually correct. However, this also results in "WITH" being suggested after
> "WHERE", which is not permitted by the syntax.

True. How about other places? That is, where we check the completion
after "WITH (". For example:

-   /* Complete COPY <sth> TO filename WITH ( */
-   else if (Matches("COPY|\\copy", MatchAny, "TO", MatchAny, "WITH", "("))
+   /* Complete COPY <sth> TO [PROGRAM] filename WITH ( */
+   else if (Matches("COPY|\\copy", MatchAny, "TO",
MatchAnyExcept("PROGRAM"), "WITH", "(") ||
+            Matches("COPY|\\copy", MatchAny, "TO", "PROGRAM",
MatchAny, "WITH", "("))

Does it make sense to replace these two lines with the following one line?

else if (Matches("COPY|\\copy", MatchAny, "TO", MatchAny, MatchAnyN,
"WITH", "("))

Regards,

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

On Thu, 25 Sep 2025 14:31:18 -0700
Masahiko Sawada <sawada.mshk@gmail.com> wrote:

> > > I fixed it to use 'generator'.
> 
> LGTM. I've pushed the 0001 patch.

Thank you!

> > > > ---
> > > > -   /* Complete COPY <sth> FROM <sth> */
> > > > -   else if (Matches("COPY|\\copy", MatchAny, "FROM", MatchAny))
> > > > +   /* Complete COPY <sth> FROM [PROGRAM] <sth> */
> > > > +   else if (Matches("COPY|\\copy", MatchAny, "FROM",
> > > > MatchAnyExcept("PROGRAM")) ||
> > > > +            Matches("COPY|\\copy", MatchAny, "FROM", "PROGRAM", MatchAny))
> > > >
> > > > I see this kind of conversion many places in the patch; convert one
> > > > condition with MatchAny into two conditions with
> > > > MatchAnyExcept("PROGRAM") and '"PROGRAM", MatchAny'. How about
> > > > simplifying it using MatchAnyN. For example,
> > > >
> > > > else if (Matches("COPY|\\copy", MatchAny, "FROM", MatchAny, MatchAnyN))
> > >
> > > We could simplify this by using MatchAnyN, but doing so would cause "WITH ("
> > > or "WHERE" to be suggested after "WITH (...)", even though that is not allowed
> > > by the syntax. This could be misleading for users, so I wonder whether it is
> > > worth adding a bit of complexity to prevent possible confusion.
> >
> > There was a mistake in the previous statement: "WHERE" appearing after "WITH (...)"
> > is actually correct. However, this also results in "WITH" being suggested after
> > "WHERE", which is not permitted by the syntax.
> 
> True. How about other places? That is, where we check the completion
> after "WITH (". For example:
> 
> -   /* Complete COPY <sth> TO filename WITH ( */
> -   else if (Matches("COPY|\\copy", MatchAny, "TO", MatchAny, "WITH", "("))
> +   /* Complete COPY <sth> TO [PROGRAM] filename WITH ( */
> +   else if (Matches("COPY|\\copy", MatchAny, "TO",
> MatchAnyExcept("PROGRAM"), "WITH", "(") ||
> +            Matches("COPY|\\copy", MatchAny, "TO", "PROGRAM",
> MatchAny, "WITH", "("))
> 
> Does it make sense to replace these two lines with the following one line?
> 
> else if (Matches("COPY|\\copy", MatchAny, "TO", MatchAny, MatchAnyN,
> "WITH", "("))

That works for other places where options are suggested after "WITH (" and
"WHERE" is suggested after "WITH (*)".

I've attached updated patches using MatchAnyN following your suggestion.

The patch 0002 was also changed to use Matches, since MathAnyN cannot be used
with HeadMatches. I don't think this is a problem, because the COPY command cannot
be nested and "COPY or "\copy" would always appear at the beginning.

Regards,
Yugo Nagata

-- 
Yugo Nagata <nagata@sraoss.co.jp>