What does "Found project reference without a matching metadata reference" indicate?

[aidapsibr]

I get a lot of these warnings and I just want to make sure everything is OK. Can this be documented somewhere if it should be addressed, am I not following a best practice possibly, or should I ignore this?

Version: 3.0.2+658b525df6382ed33b20345ba5b037c8515c9a71

[jmarolf]

I believe this is coming from MSBuildWorkspace @DustinCampbell ?

[DustinCampbell]

It's when there's a project reference in a project that can't be matched up with an output path (code). I would guess this is happening with multi-targeted projects?

[jmarolf]

I would guess this is happening with multi-targeted projects?

That is where I observed it happening (in roslyn anyway). For the purposes of dotnet-format do you think it is safe to not report this case?

[DustinCampbell]

Sure. I think it's safe not to report it in dotnet-format

[benmccallum]

I'm getting this too. MVC5 apps point to some class libraries and it comes up for a few of my class libraries that are just net472 targeted. Those class libraries point to nuget packages that have multiple targets, but other than that they are fairly standard.

[AnthonyMastrean]

I see this message when I run dotnet format in workspace with a solution. I even see it when I run it in a project subdirectory that's associated with a solution (using -w). I don't know if the solution is relevant, but I never create projects without one, so... 🤷‍♂

As for multi-targeting, these projects are all netcoreapp2.2 only.

[JoeRobich]

Closing this issue now that Project load warnings are only logged during when the log level is set to verbose.

[tiesmaster]

@JoeRobich Actually, I think this is something that should be solved by dotnet-format. Although, these warnings only show up when you set the log level to verbose, you do get a hint of them with the default log level, it shows up as:

Warnings were encountered while loading the workspace. Set the verbosity option to the 'diagnostic' level to log warnings.

The sole reason I found out about the given warning is that my project now always has this warning, and I had to dig in to find out what the problem was, and to finally find out that this is something I can ignore. So this also means that I'll always will receive this warning, even though, I cannot fix it. This will lead to "more broken windows" as when more warnings show up, I wouldn't know, since I wouldn't give any attention to the fact that I have warnings.

[jmarolf]

I think we should not still log this in verbose mode, but not tell the user that the project loaded with warnings if this is the only warning kind encountered. I think most of this work with require changes in roslyn but we'll track this here.

[WeihanLi]

It seemed I met the same problem, there's a sample build https://github.com/WeihanLi/WeihanLi.Common/runs/4709669170?check_suite_focus=true , and I expect dotnet-format would format my code with file header template, but nothing happens, can be reproduced with the code https://github.com/WeihanLi/WeihanLi.Common/tree/d64ce840ed0bf8f076b6706dc107bc9e80787e31

When I run dotnet format, I would get output like follows:

Warnings were encountered while loading the workspace. Set the verbosity option to the 'diagnostic' level to log warnings.

When I specific the -v=diag, I would get some Found project reference without a matching metadata reference from the output, not sure if it's the same issue, and some projects are not using the editor config in the repo, is it expected?

PS C:\projects\sources\WeihanLi.Common> dotnet format -v=diag
  The dotnet runtime version is '6.0.1'.
  The dotnet CLI version is '6.0.101'.
  Using MSBuild.exe located in 'C:\Program Files\dotnet\sdk\6.0.101\'.
  Formatting code files in workspace 'C:\projects\sources\WeihanLi.Common\WeihanLi.Common.sln'.
  Loading workspace.
    Determining projects to restore...
  All projects are up-to-date for restore.
Found project reference without a matching metadata reference: C:\projects\sources\WeihanLi.Common\src\WeihanLi.Data\WeihanLi.Data.csproj
Found project reference without a matching metadata reference: C:\projects\sources\WeihanLi.Common\src\WeihanLi.Common.Aspect.AspectCore\WeihanLi.Common.Aspect.AspectCore.csproj
Found project reference without a matching metadata reference: C:\projects\sources\WeihanLi.Common\src\WeihanLi.Common.Aspect.Castle\WeihanLi.Common.Aspect.Castle.csproj
Found project reference without a matching metadata reference: C:\projects\sources\WeihanLi.Common\src\WeihanLi.Common.Logging.Log4Net\WeihanLi.Common.Logging.Log4Net.csproj
Found project reference without a matching metadata reference: C:\projects\sources\WeihanLi.Common\src\WeihanLi.Common.Logging.Serilog\WeihanLi.Common.Logging.Serilog.csproj
  Project WeihanLi.Common(netstandard2.0) is using configuration from 'C:\projects\sources\WeihanLi.Common\.editorconfig'.
  Project WeihanLi.Common(netstandard2.0) is using configuration from 'C:\projects\sources\WeihanLi.Common\src\WeihanLi.Common\obj\Debug\netstandard2.0\WeihanLi.Common.GeneratedMSBuildEditorConfig.editorconfig'.
  Project WeihanLi.Common(netstandard2.1) is using configuration from 'C:\projects\sources\WeihanLi.Common\.editorconfig'.
  Project WeihanLi.Common(netstandard2.1) is using configuration from 'C:\projects\sources\WeihanLi.Common\src\WeihanLi.Common\obj\Debug\netstandard2.1\WeihanLi.Common.GeneratedMSBuildEditorConfig.editorconfig'.
  Project WeihanLi.Common(net6.0) is using configuration from 'C:\projects\sources\WeihanLi.Common\.editorconfig'.
  Project WeihanLi.Common(net6.0) is using configuration from 'C:\projects\sources\WeihanLi.Common\src\WeihanLi.Common\obj\Debug\net6.0\WeihanLi.Common.GeneratedMSBuildEditorConfig.editorconfig'.
  Project WeihanLi.Common(net6.0) is using configuration from 'C:\Program Files\dotnet\sdk\6.0.101\Sdks\Microsoft.NET.Sdk\analyzers\build\config\analysislevel_6_default.editorconfig'.
  Project WeihanLi.Common.Test is using configuration from 'C:\projects\sources\WeihanLi.Common\.editorconfig'.
  Project WeihanLi.Common.Test is using configuration from 'C:\projects\sources\WeihanLi.Common\test\WeihanLi.Common.Test\obj\Debug\net6.0\WeihanLi.Common.Test.GeneratedMSBuildEditorConfig.editorconfig'.
  Project WeihanLi.Common.Test is using configuration from 'C:\Program Files\dotnet\sdk\6.0.101\Sdks\Microsoft.NET.Sdk\analyzers\build\config\analysislevel_6_default.editorconfig'.

[andyleejordan]

Same as @WeihanLi. If the warning is ignorable, and only emitted in diagnostic level, it needs to not trigger "Warnings were encountered while loading the workspace."

I had this same problem, and the cause ended up being the project order in the solution file. For anyone experiencing this warning, I would encourage you to check if the referenced project is listed after the project which includes the <ProjectReference Include="..."/> statement in the solution file.