[wip] 1211 mariadb compatibility (#1440)

fixes #1211 

As we've already upgraded our minimum requirement to 7.1 there's no current need to force a constraint on dbal 2.7+.

.travis.yml

@@ -1,9 +1,12 @@
 language: php
+sudo: false
 
 env:
-  - DB_USERNAME=travis
-services:
-  - mysql
+  global:
+    - DB=mariadb
+
+addons:
+  mariadb: '10.2'
 
 php:
   - 7.1
@@ -11,8 +14,20 @@ php:
 
 matrix:
   fast_finish: true
+  include:
+    - php: 7.1
+      addons: # to prevent mariadb
+      services: mysql
+      env:
+        - DB=mysql
+    - php: 7.2
+      addons: # to prevent mariadb
+      services: mysql
+      env:
+        - DB=mysql
+
 before_install:
-  - mysql -e 'CREATE DATABASE flarum;'
+  - if [[ "$DB" == "mysql" || "$DB" == "mariadb" ]]; then mysql -e 'CREATE DATABASE flarum;'; fi
 before_script:
   - composer self-update
   - composer install
@@ -26,5 +41,3 @@ notifications:
 
 after_success:
   - bash <(curl -s https://codecov.io/bash)
-
-sudo: false

phpunit.xml

@@ -19,4 +19,9 @@
             <exclude>./tests/Install</exclude>
         </testsuite>
     </testsuites>
+    <filter>
+        <whitelist processUncoveredFilesFromWhitelist="true">
+            <directory suffix=".php">./src/</directory>
+        </whitelist>
+    </filter>
 </phpunit>

tests/Test/Concerns/CreatesForum.php

@@ -75,9 +75,10 @@ trait CreatesForum
         $data->setSetting('mail_driver', 'log');
 
         $database = $data->getDatabaseConfiguration();
-        $database['database'] = env('DB_DATABASE', 'flarum');
-        $database['username'] = env('DB_USERNAME', 'root');
-        $database['password'] = env('DB_PASSWORD', '');
+        $database['host'] = env('DB_HOST', $database['host']);
+        $database['database'] = env('DB_DATABASE', $database['database']);
+        $database['username'] = env('DB_USERNAME', $database['username']);
+        $database['password'] = env('DB_PASSWORD', $database['password']);
         $data->setDatabaseConfiguration($database);
 
         $this->configuration = $data;