@Override
    void compact(CompactionDetails details, byte[] bundleReadBuffer) {
      compactCalled = true;
      compactCallsCountdown.countDown();
      if (details == null) {
        callOrderException = new Exception("Called compact() with null details");
      } else if (!resumeCompactionCalled) {
        callOrderException = new Exception("Called compact() before calling maybeResumeCompaction()");
      }
      if (exceptionToThrowOnCompact != null) {
        throw exceptionToThrowOnCompact;
      }
    }
MockBlobStore to assist in testing {@link CompactionManager}
ambry-store/src/test/java/com/github/ambry/store/CompactionManagerTest.java