class CommentStatisticsUnitTest

class CommentStatisticsUnitTest extends UnitTestCase {
    
    /**
     * Mock statement.
     *
     * @var \Drupal\Core\Database\StatementInterface
     */
    protected $statement;
    
    /**
     * Mock select interface.
     *
     * @var \Drupal\Core\Database\Query\SelectInterface
     */
    protected $select;
    
    /**
     * Mock database connection.
     *
     * @var \Drupal\Core\Database\Connection
     */
    protected $database;
    
    /**
     * CommentStatistics service under test.
     *
     * @var \Drupal\comment\CommentStatisticsInterface
     */
    protected $commentStatistics;
    
    /**
     * Counts calls to fetchAssoc().
     *
     * @var int
     */
    protected $calls_to_fetch;
    
    /**
     * Sets up required mocks and the CommentStatistics service under test.
     */
    protected function setUp() : void {
        $this->statement = $this->getMockBuilder('Drupal\\sqlite\\Driver\\Database\\sqlite\\Statement')
            ->disableOriginalConstructor()
            ->getMock();
        $this->statement
            ->expects($this->any())
            ->method('fetchObject')
            ->willReturnCallback([
            $this,
            'fetchObjectCallback',
        ]);
        $this->select = $this->getMockBuilder('Drupal\\Core\\Database\\Query\\Select')
            ->disableOriginalConstructor()
            ->getMock();
        $this->select
            ->expects($this->any())
            ->method('fields')
            ->will($this->returnSelf());
        $this->select
            ->expects($this->any())
            ->method('condition')
            ->will($this->returnSelf());
        $this->select
            ->expects($this->any())
            ->method('execute')
            ->willReturn($this->statement);
        $this->database = $this->getMockBuilder('Drupal\\Core\\Database\\Connection')
            ->disableOriginalConstructor()
            ->getMock();
        $this->database
            ->expects($this->once())
            ->method('select')
            ->willReturn($this->select);
        $this->commentStatistics = new CommentStatistics($this->database, $this->createMock('Drupal\\Core\\Session\\AccountInterface'), $this->createMock(EntityTypeManagerInterface::class), $this->createMock('Drupal\\Core\\State\\StateInterface'), $this->database);
    }
    
    /**
     * Tests the read method.
     *
     * @see \Drupal\comment\CommentStatistics::read()
     *
     * @group Drupal
     * @group Comment
     */
    public function testRead() {
        $this->calls_to_fetch = 0;
        $results = $this->commentStatistics
            ->read([
            '1' => 'boo',
            '2' => 'foo',
        ], 'snafus');
        $this->assertEquals([
            'something',
            'something-else',
        ], $results);
    }
    
    /**
     * Return value callback for fetchObject() function on mocked object.
     *
     * @return bool|string
     *   'Something' on first, 'something-else' on second and FALSE for the
     *   other calls to function.
     */
    public function fetchObjectCallback() {
        $this->calls_to_fetch++;
        switch ($this->calls_to_fetch) {
            case 1:
                return 'something';
            case 2:
                return 'something-else';
            default:
                return FALSE;
        }
    }

}