MSBuildWorkspace 无法将带有 的项目编译到另一个项目

Question

注意我也问过这个问题(带有复制代码)on Roslyn's GitHub

创建一个包含 2 个项目(CoreLibrary 和 DownstreamLibrary)的新解决方案。

将项目引用从 DownstreamLibrary 添加到 CoreLibrary。

运行以下代码并注意 DownstreamLibrary 不再编译。

请注意，我已经尝试将 net461、netcoreapp2.1 和 netstandard2.0 作为项目的目标框架 - 每次都遇到相同的问题。

static async Task Main(string[] args)
{
    MSBuildLocator.RegisterDefaults();
    using (var workspace = MSBuildWorkspace.Create())
    {
        workspace.WorkspaceFailed += (sender, workspaceFailedArgs) => WriteLine(workspaceFailedArgs.Diagnostic.Message);
        var solution = await workspace.OpenSolutionAsync(@"c:\source\ForRoslynTest\ForRoslynTest.sln");
        WriteLine($"Loaded solution {solution.FilePath}");

        var projectTree = workspace.CurrentSolution.GetProjectDependencyGraph();
        foreach (var projectId in projectTree.GetTopologicallySortedProjects())
        {
            await CompileProject(workspace.CurrentSolution.GetProject(projectId));
        }
    }
}

private static async Task CompileProject(Project project)
{
    WriteLine($"Compiling {project.Name}. It has {project.MetadataReferences.Count} metadata references.");
    var compilation = await project.GetCompilationAsync();
    var errors = compilation.GetDiagnostics().Where(diagnostic => diagnostic.Severity == DiagnosticSeverity.Error);
    if (errors.Any())
    {
        WriteLine($"COMPILATION ERROR: {compilation.AssemblyName}: {errors.Count()} compilation errors: \n\t{string.Join("\n\t", errors.Where(e => false).Select(e => e.ToString()))}");
    }
    else
    {
        WriteLine($"Project {project.Name} compiled with no errors");
    }
}

您将收到以下输出:

Msbuild failed when processing the file 'c:\source\ForRoslynTest\DownstreamLibrary\DownstreamLibrary.csproj' with message: C:\Program Files\dotnet\sdk\2.1.602\Microsoft.Common.CurrentVersion.targets: (1548, 5): The "Microsoft.Build.Tasks.ResolveNonMSBuildProjectOutput" task could not be loaded from the assembly Microsoft.Build.Tasks.Core, Version=15.1.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a.  Confirm that the <UsingTask> declaration is correct, that the assembly and all its dependencies are available, and that the task contains a public class that implements Microsoft.Build.Framework.ITask.

Found project reference without a matching metadata reference: c:\source\ForRoslynTest\CoreLibrary\CoreLibrary.csproj

Loaded solution c:\source\ForRoslynTest\ForRoslynTest.sln

Compiling CoreLibrary. It has 113 metadata references.
Project CoreLibrary compiled with no errors

Compiling DownstreamLibrary. It has 0 metadata references.
COMPILATION ERROR: DownstreamLibrary: 3 compilation errors:
        c:\source\ForRoslynTest\DownstreamLibrary\Class1.cs(1,7): error CS0246: The type or namespace name 'System' could not be found (are you missing a using directive or an assembly reference?)
        c:\source\ForRoslynTest\DownstreamLibrary\Class1.cs(5,18): error CS0518: Predefined type 'System.Object' is not defined or imported
        c:\source\ForRoslynTest\DownstreamLibrary\Class1.cs(5,18): error CS1729: 'object' does not contain a constructor that takes 0 arguments

所以我的问题是如何修复上述错误并让 DownstreamLibrary 编译？

编辑
我 99% 确定根本原因是这个错误

The "Microsoft.Build.Tasks.ResolveNonMSBuildProjectOutput" task could not be loaded from the assembly Microsoft.Build.Tasks.Core, Version=15.1.0.0

我已经与 procmon 确认它正在加载以下 DLL(C:\其中的任务。这个 DLL 的旧版本确实有这个任务。

Answer 1

我找到了此 WorkspaceFailed 错误的手动解决方法:

[Failure] Msbuild failed when processing the with message: The "Microsoft.Build.Tasks.ResolveNonMSBuildProjectOutput" task could not be loaded from the assembly Microsoft.Build.Tasks.Core, Version=15.1.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a. Confirm that the declaration is correct, that the assembly and all its dependencies are available, and that the task contains a public class that implements Microsoft.Build.Framework.ITask.

有几个解决步骤:

关注 https://github.com/microsoft/msbuild/issues/4770我将 VS 2019 从 16.2 更新到 16.5.3 ......这并没有修复我的错误，但值得记录我这样做。

我将我的 Microsoft.Build.* 和 Microsoft.CodeAnalysis 依赖项升级到最新的，这还没有解决，同样的错误。

我导航到 C:\Program Files\dotnet\sdk，它以前有几个目录:

1.0.0/                  1.0.0-rc4-004771/  2.0.3/    2.1.505/
1.0.0-preview1-002702/  1.0.3/             2.1.202/  3.1.100/
1.0.0-preview2-003121/  1.0.4/             2.1.4/    3.1.201/
1.0.0-preview4-004233/  1.1.0/             2.1.502/  NuGetFallbackFolder/

我将其重命名为 sdk_o 并创建了一个新文件夹 C:\Program Files\dotnet\sdk，仅在 3.1.201/

中复制

成功!这个错误消失了，但是运行我的 roslyn 应用程序会导致一些错误，比如(路径被剥离)

[Failure] Msbuild failed when processing the file with message The "ProcessFrameworkReferences" task failed unexpectedly. System.IO.FileNotFoundException: Could not load file or assembly 'NuGet.Frameworks, Version=5.5.0.4, Culture=neutral, PublicKeyToken=31bf3856ad364e35'. The system cannot find the file specified. File name: 'NuGet.Frameworks, Version=5.5.0.4, Culture=neutral, PublicKeyToken=31bf3856ad364e35'

通过向我的项目添加 NuGet.ProjectModel 5.5.1 解决了这个问题，csproj 现在具有以下包引用:

   <ItemGroup>
     <PackageReference Include="Microsoft.Build" Version="16.5.0" ExcludeAssets="runtime" />
     <PackageReference Include="Microsoft.Build.Framework" Version="16.5.0" ExcludeAssets="runtime" />
     <PackageReference Include="Microsoft.Build.Locator" Version="1.2.6" />
     <PackageReference Include="Microsoft.Build.Tasks.Core" Version="16.5.0" ExcludeAssets="runtime" />
     <PackageReference Include="Microsoft.CodeAnalysis" Version="3.5.0" />
     <PackageReference Include="Microsoft.CodeAnalysis.CSharp.Workspaces" Version="3.5.0" />
     <PackageReference Include="Microsoft.CodeAnalysis.Workspaces.MSBuild" Version="3.5.0" />
     <PackageReference Include="NuGet.ProjectModel" Version="5.5.1" />
   </ItemGroup>

此代码不再有 WorkspaceFailed 事件:

Microsoft.Build.Locator.MSBuildLocator.RegisterDefaults();
var workspace = MSBuildWorkspace.Create();
workspace.WorkspaceFailed += (s, e) => { Console.WriteLine(e.Diagnostic); };
var project = await workspace.OpenProjectAsync(@"C:/path/to.csproj");     

我用 Roslyn 加载的 csproj 如下所示:

<Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
      <TargetFramework>netcoreapp3.1</TargetFramework>
      <UseWindowsForms>true</UseWindowsForms>
      <OutputType>Library</OutputType>
      <ApplicationIcon />
      <StartupObject />
   </PropertyGroup>

   <ItemGroup>
      <ProjectReference Include="..\..\dependencies\some.csproj" />
   </ItemGroup>
</Project>