Using transactions in a separate database with Drupal PHPUnit tests

Update April 2009:
I’ve started working with Mark Bennett on phpunit_setup.inc and moved it up to a github repository. Mark has adapted it to work with Drupal 5, and we’re working on a number of other related ideas as well. I’ll post updates here about our progress.

This month I’ve been experimenting with using testing ideas from Ruby on Rails while developing a Drupal module. To read more, see:

• Using MySQL transactions with Drupal unit tests
• Using a test database with Drupal unit tests

If you want to try this out yourself, follow these instructions:

1. Edit settings.php and use an array of two values for $db_url:

   $db_url["default"] = 'mysql://user:password@localhost/drupal;
   $db_url["test"] = 'mysql://user:password@localhost/drupal_test';

2. Create a new test database in MySQL:

   CREATE DATABASE drupal_test DEFAULT CHARACTER SET utf8
                               COLLATE utf8_unicode_ci;

3. Download and save phpunit_setup.inc somewhere in your Drupal application; for example in the “includes” folder.
4. Include phpunit_setup.inc at the top of each of your PHPUnit test classes. See one of the two articles above for example PHPUnit tests.

5. Execute your PHPUnit test class from the root folder of your Drupal app:

   $ cd /path/to/your/drupal-site
   $ phpunit YourClass modules/your_module/YourClassFileName.php 
   PHPUnit 3.2.21 by Sebastian Bergmann.
   ..
   Time: 0 seconds
   OK (2 tests)

For more information about how to run PHPUnit with Drupal, see: Writing your first PHPUnit test in Drupal.