public function testVerifyPeersWhenSourceAndTargetAlreadyExist()
 {
     $this->source->expects($this->once())->method('getDatabase')->willReturn('test_source_database');
     $this->source->expects($this->once())->method('getDatabaseInfo')->willReturn(array('db_name' => 'test_source_database', 'instance_start_time' => '123', 'update_seq' => '456'));
     $this->target->expects($this->once())->method('getDatabase')->willReturn('test_target_database');
     $this->target->expects($this->once())->method('getDatabaseInfo')->willReturn(array('db_name' => 'test_target_database', 'instance_start_time' => '123', 'update_seq' => '456'));
     $task = new ReplicationTask();
     $replication = new Replication($this->source, $this->target, $task);
     list($sourceInfo, $targetInfo) = $replication->verifyPeers();
     $this->assertArrayHasKey("update_seq", $sourceInfo, 'Source info not correctly returned.');
     $this->assertArrayHasKey("instance_start_time", $sourceInfo, 'Source info not correctly returned.');
     $this->assertArrayHasKey("update_seq", $targetInfo, 'Target info not correctly returned.');
     $this->assertArrayHasKey("instance_start_time", $targetInfo, 'Target info not correctly returned.');
 }