public void ReturnTrueAndMatchMessage_WhenArgumentIsDoubleNaN()
{
// Arrange.
double value = double.NaN;
// Act.
IValidationPredicateResult result = DoubleNaNValidationPredicate.Instance.Match(value);
// Assert.
Assert.IsTrue(result.IsMatch);
Assert.AreEqual("The argument is NaN.", result.Message);
}