Fix NUL characters in FORMAT() output

[dveeden]

Fixes https://bugs.mysql.com/bug.php?id=82085

In sql/sql/locale.cc there is this for bg_BG:

                          '\0',       /* thousands_sep bg_BG */
                          "\x03\x03", /* grouping      bg_BG */

Other locales that set \0 as thousounds separator have grouping set to \x80\x80, but the bg_BG locale doesn't.

The result is that FORMAT(12345.67,3,'bg_BG') has a NUL character as thousands separator.

Before this commit:

mysql> SELECT FORMAT(12345.67, 3, 'bg_BG');
+------------------------------+
| FORMAT(12345.67, 3, 'bg_BG') |
+------------------------------+
| 12 345,670                   |
+------------------------------+
1 row in set (0.001 sec)

mysql> SELECT HEX(FORMAT(12345.67, 3, 'bg_BG'));
+-----------------------------------+
| HEX(FORMAT(12345.67, 3, 'bg_BG')) |
+-----------------------------------+
| 3132003334352C363730              |
+-----------------------------------+
1 row in set (0.001 sec)

With this commit:

mysql> SELECT FORMAT(12345.67,3,'bg_BG');
+----------------------------+
| FORMAT(12345.67,3,'bg_BG') |
+----------------------------+
| 12345,670                  |
+----------------------------+
1 row in set (0.001 sec)

mysql> SELECT HEX(FORMAT(12345.67,3,'bg_BG'));
+---------------------------------+
| HEX(FORMAT(12345.67,3,'bg_BG')) |
+---------------------------------+
| 31323334352C363730              |
+---------------------------------+
1 row in set (0.001 sec)

Other options considered:

1. Change the grouping for bg_BG to \x80\x80. This would probably have the same result, but allows for newly added locales to have the same issue later on.
2. Change the thousands separator for bg_BG to (space, 0x20). This would result in output that may be visually similar depending on the client, but it seems like no thousands separator was the intended behavior.

[mysql-oca-bot]

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Thanks

[dveeden]

I confirm the code being submitted is offered under the terms of the OCA, and that I am authorized to contribute it.

[mysql-oca-bot]

Hi, thank you for your contribution. Your code has been assigned to an internal queue. Please follow
bug http://bugs.mysql.com/bug.php?id=119356 for updates.
Thanks