Use MYSQL_* environment variables for tests

- Prevent `.htconfig.php` override when present during tests.

diff --cc .travis.yml
index 82b5a5d,82b5a5d..b722fe7
--- 1/.travis.yml
--- 2/.travis.yml
+++ b/.travis.yml
@@@ -10,11 -10,11 +10,9 @@@ php
  services:
   - mysql
  env:
-- - USER=travis DB=test
++ - MYSQL_HOST=localhost MYSQL_PORT=3306 MYSQL_USERNAME=travis MYSQL_PASSWORD= MYSQL_DATABASE=test
  
  install:
   - composer install
  before_script:
   - mysql -e 'CREATE DATABASE IF NOT EXISTS test;'
-- # In order to avoid bin/worker.php warnings
-- - touch .htconfig.php

diff --cc htconfig.php
index 0e838bd,0e838bd..87c1301
--- 1/htconfig.php
--- 2/htconfig.php
+++ b/htconfig.php
@@@ -23,17 -23,17 +23,19 @@@ $db_data = 'mysqldatabasename'
  
  // Use environment variables for mysql if they are set beforehand
  if (!empty(getenv('MYSQL_HOST'))
--      && !empty(getenv('MYSQL_PORT'))
        && (!empty(getenv('MYSQL_USERNAME')) || !empty(getenv('MYSQL_USER')))
--      && !empty(getenv('MYSQL_PASSWORD'))
++      && !getenv('MYSQL_PASSWORD') === false
        && !empty(getenv('MYSQL_DATABASE'))) {
--      $db_host = getenv('MYSQL_HOST') . ':' . getenv('MYSQL_PORT');
++      $db_host = getenv('MYSQL_HOST');
++      if (!empty(getenv('MYSQL_PORT'))) {
++              $db_host .= ':' . getenv('MYSQL_PORT');
++      }
        if (!empty(getenv('MYSQL_USERNAME'))) {
                $db_user = getenv('MYSQL_USERNAME');
--      } elseif (!empty(getenv('MYSQL_USER'))) {
++      } else {
                $db_user = getenv('MYSQL_USER');
        }
--      $db_pass = getenv('MYSQL_PASSWORD');
++      $db_pass = (string) getenv('MYSQL_PASSWORD');
        $db_data = getenv('MYSQL_DATABASE');
  }
  

diff --cc tests/DatabaseTest.php
index 6edd45e,408e4b0..b53d591
--- 1/tests/DatabaseTest.php
--- 2/tests/DatabaseTest.php
+++ b/tests/DatabaseTest.php
@@@ -33,15 -33,15 +33,13 @@@ abstract class DatabaseTest extends Tes
                $base_config_file_path = stream_resolve_include_path($base_config_file_name);
                $config_file_path = dirname($base_config_file_path) . DIRECTORY_SEPARATOR . $config_file_name;
  
--              $config_string = file_get_contents($base_config_file_path);
++              if (!file_exists($config_file_path)) {
++                      $config_string = file_get_contents($base_config_file_path);
  
-               $config_string = str_replace('die(', '// die(', $config_string);
-               $config_string = str_replace('your.mysqlhost.com', 'localhost', $config_string);
-               $config_string = str_replace('mysqlusername'     , getenv('USER'), $config_string);
-               $config_string = str_replace('mysqlpassword'     , getenv('PASS'), $config_string);
-               $config_string = str_replace('mysqldatabasename' , getenv('DB'), $config_string);
 -              $config_string = str_replace('die(', '// die(');
 -              $config_string = str_replace('your.mysqlhost.com', 'localhost');
 -              $config_string = str_replace('mysqlusername'     , getenv('USER'));
 -              $config_string = str_replace('mysqlpassword'     , getenv('PASS'));
 -              $config_string = str_replace('mysqldatabasename' , getenv('DB'));
++                      $config_string = str_replace('die(', '// die(', $config_string);
  
--              file_put_contents($config_file_path, $config_string);
++                      file_put_contents($config_file_path, $config_string);
++              }
        }
  
        /**
@@@ -58,7 -58,7 +56,7 @@@
        protected function getConnection()
        {
                if (!dba::$connected) {
--                      dba::connect('localhost', getenv('USER'), getenv('PASS'), getenv('DB'));
++                      dba::connect(getenv('MYSQL_HOST') . ':' . getenv('MYSQL_PORT'), getenv('MYSQL_USERNAME'), getenv('MYSQL_PASSWORD'), getenv('MYSQL_DATABASE'));
  
                        if (dba::$connected) {
                                $app = get_app();