Re: patch: psql variables tabcomplete

Hello

2010/10/4 Itagaki Takahiro <itagaki(dot)takahiro(at)gmail(dot)com>:
> On Mon, Aug 16, 2010 at 8:32 PM, Pavel Stehule <pavel(dot)stehule(at)gmail(dot)com> wrote:
>> fixed spelling
>>
>> 2010/8/16 Pavel Stehule <pavel(dot)stehule(at)gmail(dot)com>:
>>> I found so there are not support for tabcomple of psql variables.
>
> Contents & Purpose
> ==================
> This small patch adds support for tab-completion of \set meta command in psql.
> Variables that can be set with \set include not only user-defined ones but also
> many pre-defined ones. So, the patch is useful to remember variable names.
>
> Initial Run
> ===========
> The patch can be applied to git master with one hunk, but it's not a problem.
>  Hunk #1 succeeded at 2582 (offset 65 lines).
>
> It can be compiled with no warnings, but it might be better to add an explicit
> cast for the void * returned from realloc() (if we continue to use it;
> see below).

fixed

>
> Performance
> ===========
> Since we don't have so many variables at once in normal use, the tab completion
> won't be a performance critical part.
>
> Bugs, suggestions, etc.
> =======================
> BUG: If we have just 100 variables, there is a buffer overrun for the last
> NULL sentinel.

fixed

>
> realloc() is used in the patch, but it is rarely used in the existing codes.
> It is used in converting a single-linked list into an array, but we could
> remove it if we use two loops (for length and for copying). Or, we will
> still use realloc, a wrapper for pg_realloc() might be better than using
> realloc() directly to avoid "out of memory" checks for each callee.
>
> We don't have commands for display a list of such variables and \echo is
> not tab-completed even with the patch. "Only supported by \set" might be
> a bit unbalanced.
>

it's good idea. I looked on it - and it is job for other patch. Some
test are in experimental patch. But this needs more work - output is
little bit ugly - I thing so prefix and suffix should not be showed.
So psql autocomplete should to work with some prefixes and suffixes
and this needs a significant changes - so it isn't possible in this
moment - just point for ToDo.

Thank you very much for review.

Regards

Pavel Stehule

> --
> Itagaki Takahiro
>