Assert string as Guid with Fluent Assertions

Question

Is there a way to assert if an incomming string is a Guid using Fluent Assertions?

Something like

var guid = "f0c70613-2667-4a9a-8c2c-69006e100d790";
guid.Should().BeOfType<Guid>();

It would involve casting the input string to a Guid type and that would be ok.

Currently using Guid.Parse(guid); and relying on the exception on incorrect input, but it's not very fluent-like.

Answer 1

Using Guid.TryParse in a Fluent Style:

var guid = "f0c70613-2667-4a9a-8c2c-69006e100d790";
guid.Should().Match(g => Guid.TryParse(g, out _));

Using Guid.Parse with Exception Assertion:

var guid = "f0c70613-2667-4a9a-8c2c-69006e100d790";
Action act = () => Guid.Parse(guid);
act.Should().NotThrow<FormatException>();

Custom Assertion Method for String to Guid:

public static class GuidAssertions
{
    public static void ShouldBeGuid(this string value)
    {
        value.Should().Match(g => Guid.TryParse(g, out _), "because the string should be a valid GUID.");
    }
}

Then you can use it like this:

var guid = "f0c70613-2667-4a9a-8c2c-69006e100d790";
guid.ShouldBeGuid();