@Test
  public void testNullStoreKeyFactory() throws IOException {
    try {
      new BlobIdTransformer(null, factory.getStoreKeyConverter());
      fail("Did not throw NullPointerException");
    } catch (NullPointerException e) {
      //expected
    }
  }
Tests creating the transformer with a null StoreKeyFactory
ambry-replication/src/test/java/com/github/ambry/replication/BlobIdTransformerTest.java