public void testFileHandler_readFileAsString_invalid()
        {
            String      expectedString = "empty";
            fileHandler fh             = new file_handler.fileHandler();

            Assert.AreEqual(expectedString, fh.readFileAsString());
        }
        public void testFileHandler_readFileAsString_valid()
        {
            String      expectedString = "4 2 - 1\n- - -2\n3 - 2 -\n- 4 - 3";
            fileHandler fh             = new file_handler.fileHandler();

            fh.getFileName("4x4.txt");
            Assert.AreEqual(Regex.Replace(expectedString, @"[\u000A\u000B\u000C\u000D\u2028\u2029\u0085 ]+", String.Empty), Regex.Replace(fh.readFileAsString(), @"[\u000A\u000B\u000C\u000D\u2028\u2029\u0085 ]+", String.Empty));
        }