Any working samples how to leverage IVsSingleFileGeneratorAsync

[cloudfy]

The IVsSingleFileGeneratorAsync is now part of 17.11.* SDK however though the interface is part of the VS SDK, there are no samples nor reference to this.

[cloudfy]

dumping

[rezanid]

BTW, I went ahead and implemented it. I then registered it the same way you would register a standard IVsSingleFileGenerator, and of course it was not called at all. @madskristensen, any tip to put us in the right path?

[drewnoakes]

Here's a sample that Works On My Machine:

Package

using Microsoft.VisualStudio.Shell;
using Microsoft.VisualStudio.TextTemplating.VSHost;
using System;
using System.Runtime.InteropServices;

namespace SingleFileGeneratorExample
{
    [PackageRegistration(UseManagedResourcesOnly = true, AllowsBackgroundLoading = true)]
    [ProvideCodeGenerator(typeof(MyGenerator), "MyGenerator", "Generates files and stuff", generatesDesignTimeSource: true)]
    [Guid(PackageGuidString)]
    public sealed class SingleFileGeneratorExamplePackage : AsyncPackage
    {
        public const string PackageGuidString = "eeb91184-c84e-4b3b-be8e-cad7813122a5";
    }
}

Generator

using Microsoft.VisualStudio;
using Microsoft.VisualStudio.Shell.Generators;
using Microsoft.VisualStudio.Shell.Interop;
using System;
using System.IO;
using System.Runtime.InteropServices;
using System.Text;
using System.Threading;
using System.Threading.Tasks;

namespace SingleFileGeneratorExample
{
    [Guid("6830520F-A48A-44F2-8430-608F3B4D38B7")]
    public sealed class MyGenerator : IVsSingleFileGenerator, IVsSingleFileGeneratorAsync
    {
        public int DefaultExtension(out string pbstrDefaultExtension)
        {
            pbstrDefaultExtension = ".gen";
            return VSConstants.S_OK;
        }

        public int Generate(string wszInputFilePath, string bstrInputFileContents, string wszDefaultNamespace, IntPtr[] rgbOutputFileContents, out uint pcbOutput, IVsGeneratorProgress pGenerateProgress)
        {
            byte[] outputBytes = Encoding.UTF8.GetBytes($"// Content written via {nameof(IVsSingleFileGenerator)}");

            rgbOutputFileContents[0] = Marshal.AllocCoTaskMem(outputBytes.Length);
            Marshal.Copy(outputBytes, 0, rgbOutputFileContents[0], outputBytes.Length);
            pcbOutput = (uint)outputBytes.Length;

            return VSConstants.S_OK;
        }

        public async Task<GeneratorResult> GenerateAsync(string inputFilePath, string inputFileContents, string defaultNamespace, Stream outputStream, IVsGeneratorProgress generatorProgress, CancellationToken cancellationToken = default)
        {
            using (var writer = new StreamWriter(outputStream))
            {
                await writer.WriteLineAsync($"// Content written via {nameof(IVsSingleFileGeneratorAsync)}");
            }

            return GeneratorResult.Success;
        }

        public Task<string> GetDefaultExtensionAsync(CancellationToken cancellationToken = default)
        {
            return Task.FromResult(".gen");
        }
    }
}

Sticking these in a VSIX project and running it, you can then hit both the sync or async paths for legacy and modern .csproj files, respectively.

[rezanid]

Thanks a lot! I will add this to my package and test carefully. Maybe something's wrong with my package 🤔

[rezanid]

It works perfectly!

I started with your sample and integrated it into my package - it worked immediately in an SDK-style .csproj. Then I replaced the sample code with my own logic, and it still worked. Eventually I discovered the issue was in my test setup: I was generating classic .csproj files instead of SDK-style ones 😞 The one thing I trusted!

Warning

Important for future readers:
IVsSingleFileGeneratorAsync only works for SDK-style projects because they use the CPS project system. If you need to support classic .csproj projects as well, you’ll also need to implement IVsSingleFileGenerator.

Thanks a lot @drewnoakes for your support!

I’ll try to submit a PR to add a sample implementation to the repo.