Program: 53067
Project: 53067
Buggy source:
private ListenableFuture<Boolean> attemptTwoLevelStore(final ArtifactInfo info,final BorrowablePath output){
  ListenableFuture<Optional<String>> contentHash=Futures.transformAsync(Futures.<Void>immediateFuture(null),new AsyncFunction<Void,Optional<String>>(){
    @Override public ListenableFuture<Optional<String>> apply(    Void input) throws Exception {
      long fileSize=projectFilesystem.getFileSize(output.getPath());
      if (!performTwoLevelStores || fileSize < minimumTwoLevelStoredArtifactSize || (maximumTwoLevelStoredArtifactSize.isPresent() && fileSize > maximumTwoLevelStoredArtifactSize.get())) {
        return Futures.immediateFuture(Optional.<String>absent());
      }
      long hashComputationStart=System.currentTimeMillis();
      String hashCode=projectFilesystem.computeSha1(output.getPath()) + "String_Node_Str";
      long hashComputationEnd=System.currentTimeMillis();
      secondLevelHashComputationTimeMs.addSample(hashComputationEnd - hashComputationStart);
      return Futures.transform(delegate.store(ArtifactInfo.builder().addRuleKeys(new RuleKey(hashCode)).build(),output),Functions.constant(Optional.of(hashCode)));
    }
  }
,listeningExecutorService);
  return Futures.transformAsync(contentHash,new AsyncFunction<Optional<String>,Boolean>(){
    @Override public ListenableFuture<Boolean> apply(    Optional<String> contentHash) throws Exception {
      if (!contentHash.isPresent()) {
        return Futures.immediateFuture(false);
      }
      ImmutableMap<String,String> metadataWithCacheKey=ImmutableMap.<String,String>builder().putAll(info.getMetadata()).put(METADATA_KEY,contentHash.get()).build();
      return Futures.transform(delegate.store(ArtifactInfo.builder().setRuleKeys(info.getRuleKeys()).setMetadata(metadataWithCacheKey).build(),BorrowablePath.notBorrowablePath(emptyFilePath)),Functions.constant(true));
    }
  }
,listeningExecutorService);
}

Fixed version (ground truth):
private ListenableFuture<Boolean> attemptTwoLevelStore(final ArtifactInfo info,final BorrowablePath output){
  return Futures.transformAsync(Futures.<Void>immediateFuture(null),new AsyncFunction<Void,Boolean>(){
    @Override public ListenableFuture<Boolean> apply(    Void input) throws Exception {
      long fileSize=projectFilesystem.getFileSize(output.getPath());
      if (!performTwoLevelStores || fileSize < minimumTwoLevelStoredArtifactSize || (maximumTwoLevelStoredArtifactSize.isPresent() && fileSize > maximumTwoLevelStoredArtifactSize.get())) {
        return Futures.immediateFuture(false);
      }
      long hashComputationStart=System.currentTimeMillis();
      String hashCode=projectFilesystem.computeSha1(output.getPath()) + "String_Node_Str";
      long hashComputationEnd=System.currentTimeMillis();
      secondLevelHashComputationTimeMs.addSample(hashComputationEnd - hashComputationStart);
      ImmutableMap<String,String> metadataWithCacheKey=ImmutableMap.<String,String>builder().putAll(info.getMetadata()).put(METADATA_KEY,hashCode).build();
      return Futures.transform(Futures.allAsList(delegate.store(ArtifactInfo.builder().setRuleKeys(info.getRuleKeys()).setMetadata(metadataWithCacheKey).build(),BorrowablePath.notBorrowablePath(emptyFilePath)),delegate.store(ArtifactInfo.builder().addRuleKeys(new RuleKey(hashCode)).build(),output)),Functions.constant(true));
    }
  }
);
}