public void not_write_in_file_when_exception()
{
var numbers = "-1";
Action operation = () => SaveAction.Run(_save, numbers);
File.Exists(_path).Should().Be(false);
operation.Should().Throw <Exception>().WithMessage("Can not get result due to an exception: negatives not allowed: " + numbers);
}
public void write_in_file_StringCalculatorAdd_result()
{
var numbers = "1,2\n4";
SaveAction.Run(_save, numbers);
_sr = new StreamReader(_path);
var writeLine = _sr.ReadToEnd();
_sr.Close();
writeLine.Should().Contain(numbers.Replace("\n", "[\\n]") + " = " + StringCalculator.Add(numbers));
}