SatorImaging.StaticMemberAnalyzer 1.0.0

Static Field Analyzer for C# / .NET

Roslyn-based analyzer for C# to provide diagnostics of static fields and properties (not yet) initialization.

• Wrong order of static field declaration
• Cross-Referencing Problem of static field across type
• TODO: static property initialization diagnostics

Cross-Referencing Problem

It is a design bug which makes all things complex. Not only that but also it causes initialization error only when meet a specific condition.

So that it must be fixed even if app works correctly at a moment, to prevent simple but complicated bug which is hard to find in large code base by hand. As you know static fields will never report error when initialization failed!!

It could be happened when reordering field declarations on refactoring large code base.

class A {
    public static int Value = B.Other;
    public static int Other = 310;
}

class B {
    public static int Other = 620;
    public static int Value = A.Other;  // will be '0' not '310'
}

public static class Test
{
	public static void Main()
	{
		System.Console.WriteLine(A.Value);  // 620
		System.Console.WriteLine(A.Other);  // 310
		System.Console.WriteLine(B.Value);  // 0   👈👈👈
		System.Console.WriteLine(B.Other);  // 620

        // when changing class member access order, it works correctly 🤣
        // see the following for details
		//System.Console.WriteLine(B.Value);  // 310  👈 correct!!
		//System.Console.WriteLine(B.Other);  // 620
		//System.Console.WriteLine(A.Value);  // 620
		//System.Console.WriteLine(A.Other);  // 310
	}
}

C# Compiler Initialization Logic

• A.Value = B.Other;
  • // 'B' initialization is started by member access
  • B.Value = A.Other; // B.Value will be 0 because reading uninitialized A.Other
  • B.Other = 620;
  • // then, assign B.Other value (620) to A.Value
• A.Other = 310; // initialized here!! this value is not assigned to B.Value

Visual Studio 2019 or Earlier

This analyzer is tested on Visual Studio 2022.

You could use this analyzer on older versions of Visual Studio. To do so, update Vsix project file by following instructions written in memo file and build project.

Devnote

TODO

• Implement static property analyzer!!