public void NonBooleanShallReturnNull()
        {
            var element = XElement.Parse(@"<language value=""1""/>");
            var result  = new FhirBooleanParser().FromXml(element);

            result.Should().BeNull();
        }
        public void ShallReturnFalse()
        {
            var element = XElement.Parse(@"<language value=""false""/>");
            var result  = new FhirBooleanParser().FromXml(element);

            result.Should().NotBeNull();
            result.Value.HasValue.Should().BeTrue();
            result.Value.GetValueOrDefault().Should().Be(false);
        }
        public void NullXmlShallReturnNull()
        {
            var result = new FhirBooleanParser().FromXml(null);

            result.Should().BeNull();
        }