Make mbstring extension mandatory

[cedric-anne]

Q	A
Bug fix?	yes
New feature?	no
BC breaks?	no
Deprecations?	no
Tests pass?	yes
Fixed tickets	see #16694

The symfony/polyfill-mbstring components only provides a partial implementation of the native mbstring extension. It will permit, for instance, to be able to correctly display the GLPI console (see #8331), but it will not be able to convert chars to the UTF7-IMAP encoding required by the mail collector. I propose to make this extension mandatory in future GLPI versions.

Related error:

glpiphplog.WARNING:   *** PHP Warning (2): iconv(): Wrong encoding, conversion from "UTF-8" to "UTF7-IMAP//IGNORE" is not allowed in /var/www/html/glpi/vendor/symfony/polyfill-mbstring/Mbstring.php at line 116
  Backtrace :
  vendor/symfony/polyfill-mbstring/Mbstring.php:116  iconv()
  ...or/symfony/polyfill-mbstring/bootstrap80.php:15 Symfony\Polyfill\Mbstring\Mbstring::mb_convert_encoding()
  src/MailCollector.php:1419                         mb_convert_encoding()
  src/MailCollector.php:707                          MailCollector->connect()
  src/MailCollector.php:1913                         MailCollector->collect()
  src/CronTask.php:1018                              MailCollector::cronMailgate()
  front/cron.php:84                                  CronTask::launch()

[trasher]

I had in mind it was already required :D

[cedric-anne]

I had in mind it was already required :D

It is marked as optional, so people may forget to enable it on CLI context.

[trasher]

I often do not have that in mind, since my linux distribution does not provide 2 php configs for cli and web :)