@Before
  public void setUp() throws Exception {
    super.setUp();
    diskSpaceAllocator.initializePool(Arrays.asList(new DiskSpaceRequirements(STORE_ID, SEGMENT_CAPACITY, SEGMENT_COUNT, 0)));
    fileStore.start(SEGMENT_CAPACITY);
    when(handler.getStoreManager().getFileStore(any())).thenReturn(fileStore);

    File sourceDir = tempDir.resolve("source").toFile();
    File targetDir = tempDir.resolve("target").toFile();

    when(fileCopyInfo.getSourceReplicaId()).thenReturn(mock(ReplicaId.class));
    when(fileCopyInfo.getSourceReplicaId().getPartitionId()).thenReturn(mock(PartitionId.class));
    when(fileCopyInfo.getSourceReplicaId().getMountPath()).thenReturn(sourceDir.getAbsolutePath());

    sourcePartitionDir = tempDir.resolve(sourceDir.toPath() + File.separator +
        fileCopyInfo.getSourceReplicaId().getPartitionId().getId()).toFile();
    targetPartitionDir = tempDir.resolve(targetDir.toPath() + File.separator +
        fileCopyInfo.getTargetReplicaId().getPartitionId().getId()).toFile();

    assertTrue(sourcePartitionDir.mkdirs());
    assertTrue(targetPartitionDir.mkdirs());
  }
Sets up the test environment.
Creating source and target directories for file copy.
source and target directories further contain partition sub-directory
ambry-file-transfer/src/test/java/com/github/ambry/filetransfer/handler/StoreFileCopyHandlerIntegTest.java