FLTFY09: Auto initiate target is invalid

Type Name	FLTFY09_AutoInitializeWithAttributeAnalyzer
Diagnostic Id	FLTFY09
Category	Usage
Severity	Warning
Is Enabled By Default	Yes

Cause

The AutoInitializeWith attribute references a member that does not exist, is not static, requires parameters, or does not return the expected type.

Rule Description

AutoInitializeWith allows a static field, property or parameterless static factory method to be used. When the attribute references a member that cannot be resolved, Fluentify cannot determine how to create a default value.

For example:

[AutoInitializeWith(nameof(Create))]
public sealed class Dependent
{
    private Dependent()
    {
    }

    private static Dependent Create(int value) => new();
}

In this case, the Create method requires a parameter, so the analyzer flags the attribute usage.

How to Fix Violations

Update the attribute to reference a static field, property or parameterless static factory method that returns the target type, or remove the attribute if no such member is available.

[AutoInitializeWith(nameof(Default))]
public sealed class Dependent
{
    private Dependent(string name)
    {
        Name = name;
    }

    public static Dependent Default => new("Unknown");

    public string Name { get; }
}

How to Suppress Violations

It is not recommended to suppress the rule. Instead, it is suggested that the AutoInitializeWith attribute be removed, or alternatively, the target for AutoInitializeWith be implemented per specification.

If suppression is desired, one of the following approaches can be used:

#pragma warning disable FLTFY09 // Auto initiate target is invalid
[AutoInitializeWith(nameof(Default))]
public sealed class Dependent
#pragma warning restore FLTFY09 // Auto initiate target is invalid

or alternatively:

using System.Diagnostics.CodeAnalysis;
using Fluentify;

[AutoInitializeWith(nameof(Default))]
[SuppressMessage("Design", "FLTFY09:Auto initiate target is invalid", Justification = "Explanation for suppression")]
public sealed class Dependent

How to Disable FLTFY09

It is not recommended to disable the rule, as this may result in some confusion if expected extension methods are not present.

# Disable FLTFY09: Auto initiate target is invalid
[*.cs]
dotnet_diagnostic.FLTFY09.severity = none