Support non-nullable value types with the InitRequiredForNotNullAttribute

The InitRequiredForNotNullAttribute is really great, we’ve activated it in all our projects but there is one missing piece in my opinion: the non-nullable value types!

Consider this code:

using System;

class Program
{
    static void Main()
    {
        _ = new Person
        {
            Name = "Foo"
        };
    }
}

class Person
{
    public string Name { get; set; }

    public DateTime BirthDate { get; set; }
}

I’m expecting to get the CSE001 error but actually not because BirthDate is a value type.

Would that be possible to implement the same behavior as for non-nullable reference types? That would be awesome.

Thank you

[vsilvar]

@cezarypiatek Tested this change and it’s working, but I found something I wouldn’t expect.

Given the following code:

using SmartAnalyzers.CSharpExtensions.Annotations;

[assembly: InitRequiredForNotNull]
namespace AnalyzerTest
{
    class Program
    {
        static void Main()
        {
            _ = new Person
            {
                Name = "Foo",
                Age = 18
            };
        }
    }

    class Person
    {
        public string Name { get; set; }
        public int Age { get; set; }
        //[InitOptional]
        public bool IsAdmin { get; set; } = false;
    }
}

I get CSE001 - Missing initialization for properties: - IsAdmin, which I wouldn’t expect as a default value is being set. At the very least an [InitOptional] attribute could exist to allow disabling the initialization checks for a single property.

– Edit: Thinking about this again, it’s probably only an issue when using the attribute globally in the assembly/type, as otherwise you just wouldn’t specify the attribute for the property. Anyway, I think it still makes sense to have a [InitOptional] for such cases.

[cezarypiatek]

@jmevel @vsilvar thanks for the feedback. I’ve just added [InitOptional] which allows for excluding a specific member or whole type from the mandatory init imposed on the higher level by [InitRequired] or [InitRequiredForNotNullAttribute]. Should be available in v4.1

Please let me know how do you find the current behavior. I’m not sure if CSE004: InitOnlyOptional requires default value should be reported for fields marked with [InitOptional as well. I haven’t implemented it but I can do it. What do you think?