I'm getting an error when building my SG

[iam3yal]

I'm writing a fairly simple SG but for some reason I'm getting the following error and I'm not quite sure why I'm getting it.

1>------ Build started: Project: EventGenerator.Driver, Configuration: Debug Any CPU ------
1>C:\Program Files\Microsoft Visual Studio\2022\Community\MSBuild\Current\Bin\Roslyn\Microsoft.CSharp.Core.targets(89,5): error :
1>C:\Program Files\Microsoft Visual Studio\2022\Community\MSBuild\Current\Bin\Roslyn\Microsoft.CSharp.Core.targets(89,5): error : Unhandled Exception: System.ArgumentException: Illegal characters in path.
1>C:\Program Files\Microsoft Visual Studio\2022\Community\MSBuild\Current\Bin\Roslyn\Microsoft.CSharp.Core.targets(89,5): error :    at System.IO.Path.CheckInvalidPathChars(String path, Boolean checkAdditional)
1>C:\Program Files\Microsoft Visual Studio\2022\Community\MSBuild\Current\Bin\Roslyn\Microsoft.CSharp.Core.targets(89,5): error :    at System.IO.Path.Combine(String path1, String path2, String path3)
1>C:\Program Files\Microsoft Visual Studio\2022\Community\MSBuild\Current\Bin\Roslyn\Microsoft.CSharp.Core.targets(89,5): error :    at Microsoft.CodeAnalysis.GeneratorDriver.ParseAdditionalSources(ISourceGenerator generator, ImmutableArray`1 generatedSources, CancellationToken cancellationToken)
1>C:\Program Files\Microsoft Visual Studio\2022\Community\MSBuild\Current\Bin\Roslyn\Microsoft.CSharp.Core.targets(89,5): error :    at Microsoft.CodeAnalysis.GeneratorDriver.RunGeneratorsCore(Compilation compilation, DiagnosticBag diagnosticsBag, Func`2 generatorFilter, CancellationToken cancellationToken)
1>C:\Program Files\Microsoft Visual Studio\2022\Community\MSBuild\Current\Bin\Roslyn\Microsoft.CSharp.Core.targets(89,5): error :    at Microsoft.CodeAnalysis.GeneratorDriver.RunGeneratorsAndUpdateCompilation(Compilation compilation, Compilation& outputCompilation, ImmutableArray`1& diagnostics, CancellationToken cancellationToken)
1>C:\Program Files\Microsoft Visual Studio\2022\Community\MSBuild\Current\Bin\Roslyn\Microsoft.CSharp.Core.targets(89,5): error :    at Microsoft.CodeAnalysis.CommonCompiler.RunGenerators(Compilation input, String generatedFilesBaseDirectory, ParseOptions parseOptions, ImmutableArray`1 generators, AnalyzerConfigOptionsProvider analyzerConfigOptionsProvider, ImmutableArray`1 additionalTexts, DiagnosticBag generatorDiagnostics)
1>C:\Program Files\Microsoft Visual Studio\2022\Community\MSBuild\Current\Bin\Roslyn\Microsoft.CSharp.Core.targets(89,5): error :    at Microsoft.CodeAnalysis.CommonCompiler.CompileAndEmit(TouchedFileLogger touchedFilesLogger, Compilation& compilation, ImmutableArray`1 analyzers, ImmutableArray`1 generators, ImmutableArray`1 additionalTextFiles, AnalyzerConfigSet analyzerConfigSet, ImmutableArray`1 sourceFileAnalyzerConfigOptions, ImmutableArray`1 embeddedTexts, DiagnosticBag diagnostics, ErrorLogger errorLogger, CancellationToken cancellationToken, CancellationTokenSource& analyzerCts, AnalyzerDriver& analyzerDriver, Nullable`1& generatorTimingInfo)
1>C:\Program Files\Microsoft Visual Studio\2022\Community\MSBuild\Current\Bin\Roslyn\Microsoft.CSharp.Core.targets(89,5): error :    at Microsoft.CodeAnalysis.CommonCompiler.RunCore(TextWriter consoleOutput, ErrorLogger errorLogger, CancellationToken cancellationToken)
1>C:\Program Files\Microsoft Visual Studio\2022\Community\MSBuild\Current\Bin\Roslyn\Microsoft.CSharp.Core.targets(89,5): error :    at Microsoft.CodeAnalysis.CommonCompiler.Run(TextWriter consoleOutput, CancellationToken cancellationToken)
1>C:\Program Files\Microsoft Visual Studio\2022\Community\MSBuild\Current\Bin\Roslyn\Microsoft.CSharp.Core.targets(89,5): error :    at Microsoft.CodeAnalysis.CSharp.CommandLine.Csc.<>c__DisplayClass1_0.<Run>b__0(TextWriter tw)
1>C:\Program Files\Microsoft Visual Studio\2022\Community\MSBuild\Current\Bin\Roslyn\Microsoft.CSharp.Core.targets(89,5): error :    at Microsoft.CodeAnalysis.CommandLine.ConsoleUtil.RunWithUtf8Output[T](Func`2 func)
1>C:\Program Files\Microsoft Visual Studio\2022\Community\MSBuild\Current\Bin\Roslyn\Microsoft.CSharp.Core.targets(89,5): error :    at Microsoft.CodeAnalysis.CSharp.CommandLine.Csc.Run(String[] args, BuildPaths buildPaths, TextWriter textWriter, IAnalyzerAssemblyLoader analyzerLoader)
1>C:\Program Files\Microsoft Visual Studio\2022\Community\MSBuild\Current\Bin\Roslyn\Microsoft.CSharp.Core.targets(89,5): error :    at Microsoft.CodeAnalysis.CommandLine.BuildClient.RunLocalCompilation(String[] arguments, BuildPaths buildPaths, TextWriter textWriter)
1>C:\Program Files\Microsoft Visual Studio\2022\Community\MSBuild\Current\Bin\Roslyn\Microsoft.CSharp.Core.targets(89,5): error :    at Microsoft.CodeAnalysis.CommandLine.BuildClient.RunCompilation(IEnumerable`1 originalArguments, BuildPaths buildPaths, TextWriter textWriter, String pipeName)
1>C:\Program Files\Microsoft Visual Studio\2022\Community\MSBuild\Current\Bin\Roslyn\Microsoft.CSharp.Core.targets(89,5): error :    at Microsoft.CodeAnalysis.CommandLine.BuildClient.Run(IEnumerable`1 arguments, RequestLanguage language, CompileFunc compileFunc, CompileOnServerFunc compileOnServerFunc, ICompilerServerLogger logger)
1>C:\Program Files\Microsoft Visual Studio\2022\Community\MSBuild\Current\Bin\Roslyn\Microsoft.CSharp.Core.targets(89,5): error :    at Microsoft.CodeAnalysis.CSharp.CommandLine.Program.MainCore(String[] args)
1>C:\Program Files\Microsoft Visual Studio\2022\Community\MSBuild\Current\Bin\Roslyn\Microsoft.CSharp.Core.targets(89,5): error :    at Microsoft.CodeAnalysis.CSharp.CommandLine.Program.Main(String[] args)
1>Done building project "EventGenerator.Driver.csproj" -- FAILED.
========== Build: 0 succeeded, 1 failed, 1 up-to-date, 0 skipped ==========
========== Build completed at 15:43 and took 05.341 seconds ==========

Here are few facts:

1. Both VSCode and VS (latest versions) throw the above error.
2. Building from the CLI doesn't seems to throw the error but I'm not sure whether the SG runs.. although I know it should.

And that's all I have.

namespace EventGenerator;

using System.Text;
using Microsoft.CodeAnalysis;
using Microsoft.CodeAnalysis.CSharp.Syntax;
using Microsoft.CodeAnalysis.Text;

[Generator]
file sealed class EventGenerator : IIncrementalGenerator
{
    public void Initialize(IncrementalGeneratorInitializationContext context)
    {
    }
}

Here is a link to the project.

[jasonmalinowski]

There's something more to the story here. That path would be hit if we're parsing generated sources and something was wrong with a file path. I'd imagine that:

1. You have some detritus of another generator you wrote being included you don't realize.
2. There's a bug in some other generator that's also being included.
3. You are doing the build in some file path or with some file name that is tripping up Path.Combine.

If you change your Visual Studio build settings to output a lot more, can you copy in that full log?

The log might be very large so feel free to email it to me; my email address is in my GitHub profile.

[333fred]

This is because your generator is a file type, which mangles the name. Do not make analyzers or generators file types.

[jnm2]

Maybe worth an RSxxxx rule?

[333fred]

Yes, I took your suggestion in mind, made a time machine, traveled an hour into the past, and worked on one. dotnet/roslyn-analyzers#7501

[iam3yal]

Thank you guys!