Question

I have a web page that shows different messages according to different conditions.
I want to unit test this so I configured my project to use MVVM and I’m testing my ViewModel.

My ViewModel now format different messages. How can I test this? I don’t want to reproduce all strings, it seems dirty…

Now I’m doing this:

void test() 
{
    string message = _viewModel.DoWork();
    Assert.AreEqual(message, Resource.MyResourceText);
}

But this is a simple case. Now I have dynamic strings containing system date and other variables.

How can I test this in an elegant way? Thanks!

Answer 1

I resolved in this way:

class MyTestClass
{
    void test() 
    {
        string message = _viewModel.DoWork();
        MyAssert.StringFormatConforms(message, Resource.MyResourceText);
    }
}

class MyAssert
{
    public static void StringFormatConforms(string stringToCheck, string format)
    {
        // replace {0}, {1} with .*
        string regex = "^" + Regex.Replace(format, "{[0-9]+}", ".*") + "$";
        bool conforms = Regex.IsMatch(stringToCheck, regex);
        if (!conforms)
            throw new AssertFailedException(String.Format("The string {0} does not conforms to format: {1}", stringToCheck, format));
    }
}

In this way I can check that my message “hi ric” must conform to “hi {0}”