private void assertException(TransformationOutput transformationOutput, Class exceptionClass) {
    assertNull("Message in output is not null", transformationOutput.getMsg());
    assertTrue("Exception from output is not " + exceptionClass.getName(),
        exceptionClass.isInstance(transformationOutput.getException()));
  }
Runs all the {@link Pair#getFirst()} outputs from the {@link Pair} list through
the {@link StoreKeyConverter} storeKeyConverter.
Intended to be run so that the StoreKeyConverter's
{@link StoreKeyConverter#getConverted(StoreKey)} method can
work on any of the pairs' getFirst() outputs.
@param pairs
@param storeKeyConverter
@throws Exception {@link StoreKeyConverter#convert(Collection)} may throw an Exception
ambry-replication/src/test/java/com/github/ambry/replication/BlobIdTransformerTest.java