Arrays.sort(types);
        assertEquals("image", types[0]);
        assertEquals("pdf", types[1]);
        assertEquals("text", types[2]);
    }

    @Test
    public void test_getTypes_withDuplicates() {
        fileTypeHelper.add("application/pdf", "document");
        fileTypeHelper.add("application/msword", "document");
        fileTypeHelper.add("text/plain", "text");