Re: Support tab completion for upper character inputs in psql

On 07.01.22 06:17, tanghy.fnst@fujitsu.com wrote:
> On Friday, January 7, 2022 1:08 PM, Japin Li <japinli@hotmail.com> wrote:
>> +/*
>> + * pg_string_tolower - Fold a string to lower case if the string is not quoted
>> + * and only contains ASCII characters.
>> + * For German/Turkish etc text, no change will be made.
>> + *
>> + * The returned value has to be freed.
>> + */
>> +static char *
>> +pg_string_tolower_if_ascii(const char *text)
>> +{
>>
>> s/pg_string_tolower/pg_string_tolower_if_ascii/ for comments.
>>
> 
> Thanks for your review.
> Comment fixed in the attached V11 patch.

As I just posted over at [0], the tab completion of enum values appears 
to be broken at the moment, so I can't really analyze what impact your 
patch would have on it.  (But it makes me suspicious about the test case 
in your patch.)  I suspect it would treat enum labels as 
case-insensitive, which would be wrong.  But we need to fix that issue 
first before we can proceed here.

The rest of the patch seems ok in principle, since AFAICT enums are the 
only query result in tab-complete.c that are not identifiers and thus 
subject to case issues.

I would perhaps move the pg_string_tolower_if_ascii() calls to before 
escape_string() in each case.  It won't make a difference to the result, 
but it seems conceptually better.


[0]: 
https://www.postgresql.org/message-id/8ca82d89-ec3d-8b28-8291-500efaf23b25@enterprisedb.com