MSBuildWorkspace无法将具有 的项目编译到另一个项目

Question

注意，我也曾问过这个问题（带有复制代码）on Roslyn's GitHub

• 使用2个项目（CoreLibrary和DownstreamLibrary）创建新的解决方案。
• 将项目参考从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解决以上错误并让DownstreamLibrary进行编译？

编辑我99％确信根本原因是此错误

无法从程序集Microsoft.Build.Tasks.Core，版本= 15.1.0.0中加载“ Microsoft.Build.Tasks.ResolveNonMSBuildProjectOutput”任务

我已用procmon确认它正在加载以下DLL（C：\ Program Files \ dotnet \ sdk \ 2.1.602 \ Microsoft.Build.Tasks.Core.dll），我已用ILSpy确认DOESN' T中有ResolveNonMSBuildProjectOutput任务。此DLL did的较旧版本具有此任务。

Answer 1

我找到了解决此异常的手动方法：

[[Failure] Msbuild在处理with消息时失败：无法从程序集中Microsoft.Build.Tasks.Core，版本= 15.1.0.0，Culture = neutral，PublicKeyToken加载“ Microsoft.Build.Tasks.ResolveNonMSBuildProjectOutput”任务= b03f5f7f11d50a3a。确认声明正确无误，并保证程序集及其所有依赖项都可用，并且任务包含实现Microsoft.Build.Framework.ITask的公共类。

有一些解决步骤：

1. 跟随https://github.com/microsoft/msbuild/issues/4770我将VS 2019从16.2更新到16.5.3 ...这没有修复我的错误，但是值得记录一下我这样做了。
2. 我导航到C：\ Program Files \ dotnet \ sdk，该目录以前有几个目录：

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/

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

成功！该错误消失了，但是运行我的roslyn应用程序后导致了一些错误，例如（路径被剥离）

[[Failure] Msbuild在处理带有消息的文件时失败，“ ProcessFrameworkReferences”任务意外失败。 System.IO.FileNotFoundException：无法加载文件或程序集'NuGet.Frameworks，版本= 5.5.0.4，区域性=中性，PublicKeyToken = 31bf3856ad364e35'。该系统找不到指定的文件。文件名：'NuGet.Frameworks，版本= 5.5.0.4，文化=中性，PublicKeyToken = 31bf3856ad364e35'

通过在我的项目中添加NuGet.ProjectModel 5.5.1解决了这个问题，csproj现在具有以下程序包引用：

   <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>

此代码没有更多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");     

我正在与Roslyn一起加载的csproj看起来如下：

<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>