We support conf.php style configuration too.

framework/Db/doc/Horde/Db/README_TESTING

@@ -16,13 +16,15 @@ As long as PHP has the PDO SQLite driver (which is enabled by default), the
 SQLite tests will always be run. This is possible using the sqlite:memory
 database; no file access or permissions are required.
 
-For the other adapters, the Horde_Db test suite looks for environment variables
-named DB_ADAPTER_$driverName_TEST_CONFIG. For the MySQLi driver, that would be
-DB_ADAPTER_MYSQLI_TEST_CONFIG. For the PDO PostgreSQL driver, that would be
-DB_ADAPTER_PDO_PGSQL_TEST_CONFIG, and so on. The value of the environment
-variable is a JSON string with the configuration array for the adapter. Here is
-an example for setting up a test DSN for the MySQL test database on localhost,
-connecting as the user horde_db with no password:
+For the other adapters, the Horde_Db test suite looks for the configuration
+file conf.php, with an example configuration found at the conf.php.dist file,
+or for environment variables named DB_ADAPTER_$driverName_TEST_CONFIG. For the
+MySQLi driver, that would be DB_ADAPTER_MYSQLI_TEST_CONFIG. For the PDO
+PostgreSQL driver, that would be DB_ADAPTER_PDO_PGSQL_TEST_CONFIG, and so
+on. The value of the environment variable is a JSON string with the
+configuration array for the adapter. Here is an example for setting up a test
+DSN for the MySQL test database on localhost, connecting as the user horde_db
+with no password:
 
 {"username":"horde_db","dbname":"test","host":"localhost"}