Visual Studio Compiles Successfully but Roslyn Balks

Question

I'm writing a C# code analyzer and running into a problem. The following source code file:

using System;

namespace J4JSoftware.Logging
{
    // added to test SharpDoc
    [AttributeUsage( validOn: AttributeTargets.Class | AttributeTargets.Interface, Inherited = false, AllowMultiple = true )]
    public class DummyAttribute : Attribute
    {
#pragma warning disable 67
        // ReSharper disable once EventNeverSubscribedTo.Global
        public event EventHandler<int> Ralph;
#pragma warning restore 67
        
#pragma warning disable 8618
        public DummyAttribute( string arg1, Type arg2 )
#pragma warning restore 8618
        {
        }

        public int TestField;
    }

    public interface IDummyInterface1
    {
        int Number { get; set; }
    }

    public interface IDummyInterface2 : IDummyInterface1
    {
        string Text { get; set; }
    }

    public interface IDummyInterface3<in T>
        where T : DummyAttribute
    {
        string GetValue( T item );

        bool TestGenericMethod<TMethod>()
            where TMethod : class, IDummyInterface1;
    }
}

compiles without any errors or warnings inside Visual Studio 2019. But it generates a CS0116 error --

A namespace cannot directly contain members such as fields or methods.

when I compile it using Roslyn. The referenced line number causing the error is line zero, "using System;".

What's causing this behavior and how do I fix it?

score 3 · Answer 1 · answered Jul 09 '20 at 20:14

Sigh. Idiot at the keyboard error. Which I'll describe here in case anyone else makes the same mistake.

To compile a project you have to first parse the source code files (and do some other things, too). I called the parser like this:

var tree = CSharpSyntaxTree.ParseText( srcFile );

but I should've called it like this:

var tree = CSharpSyntaxTree.ParseText( File.ReadAllText(srcFile) );

The parser expects source code, not a file path.

Visual Studio Compiles Successfully but Roslyn Balks

1 Answers1