Public Static Readonly Fields Trigger SA1401

[lumberjack4]

public static readonly MyClass Empty = new MyClass();

SA1401 is triggered telling me that the field must be private. Recommend ignoring the rule for public static readonly fields, as this is the .NET paradigm for creating empty objects.

[sharwell]

Considering that C# 6 made it extremely easy to expose these as properties, my vote is that we not change the current behavior. The framework contains as many examples of properties being used for this purpose (e.g. Encoding.UTF8). To resolve the issue, you can actually update your code to the following equally-succinct form, and improve your exposed API at the same time:

public static MyClass Empty { get; } = new MyClass();

I'm leaving this marked needs discussion for now to get some more feedback.

By the way, welcome to the project @lumberjack4. 😄 Thanks for taking the time to try out the product and file all these issues! 👍

[lumberjack4]

Cool! I'm still trying to remember all the new changes.

[ghost]

See #1308

[bezysoftware]

What about dependency properties? Typically when you use the "propdp" snippet you get this generated:

public static readonly DependencyProperty FooProperty =
    DependencyProperty.Register("Foo", typeof(string), typeof(Class1), new PropertyMetadata(null));

which triggers SA1401.

[sharwell]

@oatkins Can you check the behavior of StyleCop "classic" with code like the previous comment?

[oatkins]

None of the following raises SA1401 in classic SC:

public static readonly DependencyProperty MyPropertyProperty =
    DependencyProperty.Register("MyProperty", typeof(int), typeof(HasDependencyProperty), new PropertyMetadata(0));

public static readonly string MyString = "fish";

public static readonly StringBuilder Builder = new StringBuilder();

Interestingly, SC is being cautious here. My last example exposes a mutable object as a static field, which isn't good practice... but I would think that someone who's explicitly made something public static readonly probably knows what they want and why!

I currently disable SA1401 for WPF projects; I would support never reporting this case so I can turn it back on.

[vweijsters]

I would prefer that SA1401 will not be reported for public static readonly fields. The main reason being that we don't want to force people to change (a lot of) their code when migrating to StyleCop.Analyzers. A secondary reason to change the current behavior would be the dependency properties, which would be a major case for quite a few people I imagine.

[sharwell]

Relabeling this as a bug.