public void test_TmpFileHasBeenDeletedAfterResponseWasClosed() throws Exception {
        // ## Arrange ##
        CurlRequest req = new MockCurlRequest(Curl.Method.POST, "http://dummy");
        req.threshold(0); // always create tmp file

        // ## Act ##
        long before = countTmpFiles();
        logger.info("Before request. Number of temp files: " + before);
        req.execute(res -> {

    protected static final Logger logger = Logger.getLogger(ContentOutputStream.class.getName());

    protected static final String PREFIX = "curl4j-";

    protected static final String SUFFIX = ".tmp";

    protected boolean done = false;

    public ContentOutputStream(final int threshold, final File tmpDir) {
        super(threshold, PREFIX, SUFFIX, tmpDir);
    }

    @Override
    public File getFile() {