};

        long result = testManager.purge(1L);
        assertTrue(result >= 0);
    }

    // Test FilePurgeVisitor getDocId
    @Test
    public void test_FilePurgeVisitor_getDocId() throws IOException {
        // Test the getDocId logic without creating actual FilePurgeVisitor
        // The logic converts path to doc ID by removing path separators
        String pathStr = "_1/_2/docid123";

     * @return the number of files purged
     */
    public long purge(final long expiry) {
        if (!baseDir.exists()) {
            return 0;
        }
        try {
            final FilePurgeVisitor visitor = new FilePurgeVisitor(baseDir.toPath(), imageExtention, expiry);
            Files.walkFileTree(baseDir.toPath(), visitor);
            return visitor.getCount();
        } catch (final Exception e) {