public function testFetch()
 {
     $git = new VersionControl_Git(dirname(__FILE__) . '/fixtures/001_VersionControl_Git');
     $instance = new VersionControl_Git_Object_Commit($git, '4ed54abb8efca38a0c794ca414b1f296279e0d85');
     $instance->fetch();
     $this->assertEquals($instance->getTree(), 'cca66138995a95b45a725e8727ee97a20a816d41');
     $this->assertFalse($instance->hasParents());
     $this->assertEquals($instance->getAuthor(), 'Kousuke Ebihara <*****@*****.**>');
     $this->assertEquals(date('YmdHis', $instance->getCreatedAt()), '20100121011001');
     $this->assertEquals($instance->getCommitter(), 'Kousuke Ebihara <*****@*****.**>');
     $this->assertEquals(date('YmdHis', $instance->getCommittedAt()), '20100121011001');
     $this->assertEquals($instance->getMessage(), 'added directories and files');
 }