public void RequiredNotNullThrowsExceptionWhenNull()
{
NullableExtensionTests nullObject = null;
Assert.Throws <InvalidStateException>(() => nullObject.RequiredNotNull());
}
public void RequiredNotNullReturnsThisWhenNotNull()
{
var nonNullObject = new NullableExtensionTests();
Assert.Equal(nonNullObject, nonNullObject.RequiredNotNull());
}