Azure hosted MariaDB instances report the wrong version number

(difficulty: "easy", requires the ability to install a Moodle instance running on a MySQL-ish DB server including that provided by Microsoft Azure)

Test using a "remote" MariaDB server provided by Microsoft Azure

TBD (Requires a free trial account to access a MariaDB instance)

Note: the version reported in the Information column in Site administration > Server > Environment is still the one wrongly reported by the PHP client, as reported here, to keep that info consistent w/ what the PHP client is telling about that DB connection. Only the version info has been improved to what the DB Server instance tells about its actual version.

Prepare the "local" test environment

1. You can use the Moodle Docker Toolbox:

   # export MOODLE_DOCKER_WWWROOT=/path/to/moodle/branch

   # cp config.docker-template.php $MOODLE_DOCKER_WWWROOT/config.php

Regression tests on MySQL

1. Select the MySQL DB Server in your Moodle Docker Toolbox and take note of the DB version as reported by the CLI comand (here: 5.7.31):

   # export MOODLE_DOCKER_DB=mysql

   # bin/moodle-docker-compose up -d && bin/moodle-docker-compose exec db mysql -V

   mysql Ver 14.14 Distrib 5.7.31, for Linux (x86_64) using EditLine wrapper

2. Run the DML tests and verify both no failures but 1 skipped test and the match between the version reported in the PHPunit CLI output and the one from the CLI comand output above (5.7.31):

   # bin/moodle-docker-wait-for-db

   # bin/moodle-docker-compose exec webserver php admin/tool/phpunit/cli/init.php

   # bin/moodle-docker-compose exec webserver vendor/bin/phpunit lib/dml/tests/dml_test.php

   Moodle 4.0dev (Build: 20200827), 16d37dc2593e137102e97a44fed5cebfb5fdf1eb

   Php: 7.2.32, mysqli: 5.7.31, OS: Linux 3.10.0-1127.19.1.el7.x86_64 x86_64

   PHPUnit 7.5.20 by Sebastian Bergmann and contributors.

   ............................................................... 63 / 106 ( 59%)

   ..........................................S 106 / 106 (100%)

   Time: 2.99 seconds, Memory: 48.00 MB

   OK, but incomplete, skipped, or risky tests!

   Tests: 106, Assertions: 1210, Skipped: 1.

Regression tests on "plain" MariaDB

1. Stop the previous test instance, select the MariaDB Server in your Moodle Docker Toolbox and take note of the DB version as reported by the CLI comand (here: 10.2.33. -MariaDB is just a suffix):

   # bin/moodle-docker-compose down -v

   # export MOODLE_DOCKER_DB=mariadb

   # bin/moodle-docker-compose up -d && bin/moodle-docker-compose exec db mysql -V

   mysql Ver 15.1 Distrib 10.2.33-MariaDB, for debian-linux-gnu (x86_64) using readline 5.2

2. Run the DML tests and verify both no failures and the match between the version reported in the PHPunit CLI output and the one from the CLI comand output above (10.2.33):

   # bin/moodle-docker-wait-for-db

   # bin/moodle-docker-compose exec webserver php admin/tool/phpunit/cli/init.php

   # bin/moodle-docker-compose exec webserver vendor/bin/phpunit lib/dml/tests/dml_test.php

   Moodle 4.0dev (Build: 20200827), 16d37dc2593e137102e97a44fed5cebfb5fdf1eb

   Php: 7.2.32, mariadb: 10.2.33, OS: Linux 3.10.0-1127.19.1.el7.x86_64 x86_64

   PHPUnit 7.5.20 by Sebastian Bergmann and contributors.

   ............................................................... 63 / 106 ( 59%)

   ........................................... 106 / 106 (100%)

   Time: 4 seconds, Memory: 48.00 MB

   OK (106 tests, 1212 assertions)