class ConnectionUnitTest

class ConnectionUnitTest extends DrupalUnitTestCase {
    protected $key;
    protected $target;
    protected $originalTarget;
    protected $monitor;
    protected $originalCount;
    protected $skipTest;
    public static function getInfo() {
        return array(
            'name' => 'Connection unit tests',
            'description' => 'Tests management of database connections.',
            'group' => 'Database',
        );
    }
    function setUp() {
        parent::setUp();
        $this->key = 'default';
        $this->originalTarget = 'default';
        $this->target = 'DatabaseConnectionUnitTest';
        // Determine whether the database driver is MySQL. If it is not, the test
        // methods will not be executed.
        // @todo Make this test driver-agnostic, or find a proper way to skip it.
        // @see http://drupal.org/node/1273478
        $connection_info = Database::getConnectionInfo('default');
        $this->skipTest = (bool) ($connection_info['default']['driver'] != 'mysql');
        if ($this->skipTest) {
            // Insert an assertion to prevent Simpletest from interpreting the test
            // as failure.
            $this->pass('This test is only compatible with MySQL.');
        }
        // Create an additional connection to monitor the connections being opened
        // and closed in this test.
        // @see TestBase::changeDatabasePrefix()
        $connection_info = Database::getConnectionInfo('default');
        Database::addConnectionInfo('default', 'monitor', $connection_info['default']);
        global $databases;
        $databases['default']['monitor'] = $connection_info['default'];
        $this->monitor = Database::getConnection('monitor');
    }
    
    /**
     * Adds a new database connection info to Database.
     */
    protected function addConnection() {
        // Add a new target to the connection, by cloning the current connection.
        $connection_info = Database::getConnectionInfo($this->key);
        Database::addConnectionInfo($this->key, $this->target, $connection_info[$this->originalTarget]);
        // Verify that the new target exists.
        $info = Database::getConnectionInfo($this->key);
        // Note: Custom assertion message to not expose database credentials.
        $this->assertIdentical($info[$this->target], $connection_info[$this->key], 'New connection info found.');
    }
    
    /**
     * Returns the connection ID of the current test connection.
     *
     * @return integer
     */
    protected function getConnectionID() {
        return (int) Database::getConnection($this->target, $this->key)
            ->query('SELECT CONNECTION_ID()')
            ->fetchField();
    }
    
    /**
     * Asserts that a connection ID exists.
     *
     * @param integer $id
     *   The connection ID to verify.
     */
    protected function assertConnection($id) {
        $list = $this->monitor
            ->query('SHOW PROCESSLIST')
            ->fetchAllKeyed(0, 0);
        return $this->assertTrue(isset($list[$id]), format_string('Connection ID @id found.', array(
            '@id' => $id,
        )));
    }
    
    /**
     * Asserts that a connection ID does not exist.
     *
     * @param integer $id
     *   The connection ID to verify.
     */
    protected function assertNoConnection($id) {
        $list = $this->monitor
            ->query('SHOW PROCESSLIST')
            ->fetchAllKeyed(0, 0);
        return $this->assertFalse(isset($list[$id]), format_string('Connection ID @id not found.', array(
            '@id' => $id,
        )));
    }
    
    /**
     * Tests Database::closeConnection() without query.
     *
     * @todo getConnectionID() executes a query.
     */
    function testOpenClose() {
        if ($this->skipTest) {
            return;
        }
        // Add and open a new connection.
        $this->addConnection();
        $id = $this->getConnectionID();
        Database::getConnection($this->target, $this->key);
        // Verify that there is a new connection.
        $this->assertConnection($id);
        // Close the connection.
        Database::closeConnection($this->target, $this->key);
        // Wait 20ms to give the database engine sufficient time to react.
        usleep(20000);
        // Verify that we are back to the original connection count.
        $this->assertNoConnection($id);
    }
    
    /**
     * Tests Database::closeConnection() with a query.
     */
    function testOpenQueryClose() {
        if ($this->skipTest) {
            return;
        }
        // Add and open a new connection.
        $this->addConnection();
        $id = $this->getConnectionID();
        Database::getConnection($this->target, $this->key);
        // Verify that there is a new connection.
        $this->assertConnection($id);
        // Execute a query.
        Database::getConnection($this->target, $this->key)
            ->query('SHOW TABLES');
        // Close the connection.
        Database::closeConnection($this->target, $this->key);
        // Wait 20ms to give the database engine sufficient time to react.
        usleep(20000);
        // Verify that we are back to the original connection count.
        $this->assertNoConnection($id);
    }
    
    /**
     * Tests Database::closeConnection() with a query and custom prefetch method.
     */
    function testOpenQueryPrefetchClose() {
        if ($this->skipTest) {
            return;
        }
        // Add and open a new connection.
        $this->addConnection();
        $id = $this->getConnectionID();
        Database::getConnection($this->target, $this->key);
        // Verify that there is a new connection.
        $this->assertConnection($id);
        // Execute a query.
        Database::getConnection($this->target, $this->key)
            ->query('SHOW TABLES')
            ->fetchCol();
        // Close the connection.
        Database::closeConnection($this->target, $this->key);
        // Wait 20ms to give the database engine sufficient time to react.
        usleep(20000);
        // Verify that we are back to the original connection count.
        $this->assertNoConnection($id);
    }
    
    /**
     * Tests Database::closeConnection() with a select query.
     */
    function testOpenSelectQueryClose() {
        if ($this->skipTest) {
            return;
        }
        // Add and open a new connection.
        $this->addConnection();
        $id = $this->getConnectionID();
        Database::getConnection($this->target, $this->key);
        // Verify that there is a new connection.
        $this->assertConnection($id);
        // Create a table.
        $name = 'foo';
        Database::getConnection($this->target, $this->key)
            ->schema()
            ->createTable($name, array(
            'fields' => array(
                'name' => array(
                    'type' => 'varchar',
                    'length' => 255,
                ),
            ),
        ));
        // Execute a query.
        Database::getConnection($this->target, $this->key)
            ->select('foo', 'f')
            ->fields('f', array(
            'name',
        ))
            ->execute()
            ->fetchAll();
        // Drop the table.
        Database::getConnection($this->target, $this->key)
            ->schema()
            ->dropTable($name);
        // Close the connection.
        Database::closeConnection($this->target, $this->key);
        // Wait 20ms to give the database engine sufficient time to react.
        usleep(20000);
        // Verify that we are back to the original connection count.
        $this->assertNoConnection($id);
    }

}