Omnisharp cannot locate Microsoft.WebAplication.targets and does not look at xbuild in default mono install

[breiter]

Environment data

dotnet --info output:

dotnet --info
.NET Command Line Tools (1.0.3)

Product Information:
 Version:            1.0.3
 Commit SHA-1 hash:  37224c9917

Runtime Environment:
 OS Name:     Mac OS X
 OS Version:  10.12
 OS Platform: Darwin
 RID:         osx.10.12-x64
 Base Path:   /usr/local/share/dotnet/sdk/1.0.3

VS Code version:

code --version
1.13.1
379d2efb5539b09112c793d3d9a413017d736f89

C# Extension version: 1.10.0

Steps to reproduce

Load a solution that includes a web project that has an import for Microsoft.WebApplication.targets

<Import Project="$(VSToolsPath)\WebApplications\Microsoft.WebApplication.targets" Condition="'$(VSToolsPath)' != ''" />

Expected behavior

All projects should load when omnisharp starts.

Visual Studio for Mac is able to load the solution without a problem.

Actual behavior

Omnisharp fails to load web project and logs a warning.

[info]: OmniSharp.DotNet.DotNetProjectSystem
        Initializing in /Users/breiter/src/wolfereiter/ifes-accounts-payable
[info]: OmniSharp.DotNet.DotNetProjectSystem
        Auto package restore: False
[info]: OmniSharp.DotNet.DotNetProjectSystem
        Update workspace context
[info]: OmniSharp.DotNet.DotNetProjectSystem
        Resolving projects references
[info]: OmniSharp.MSBuild.MSBuildProjectSystem
        MSBUILD_EXE_PATH environment variable set to /Users/breiter/.vscode/extensions/ms-vscode.csharp-1.10.0/bin/omnisharp/msbuild/MSBuild.dll
[info]: OmniSharp.MSBuild.MSBuildProjectSystem
        MSBuildExtensionsPath environment variable set to /Users/breiter/.vscode/extensions/ms-vscode.csharp-1.10.0/bin/omnisharp/msbuild
[info]: OmniSharp.MSBuild.MSBuildProjectSystem
        MSBuild will use local OmniSharp installation.
[info]: OmniSharp.MSBuild.MSBuildProjectSystem
        Detecting projects in '/Users/breiter/src/wolfereiter/ifes-accounts-payable/IFES-AccountsPayable-no-sqlproj.sln'.
[info]: OmniSharp.MSBuild.MSBuildProjectSystem
        Loading project: /Users/breiter/src/wolfereiter/ifes-accounts-payable/Ifes.AccountsPayable/Ifes.AccountsPayable.csproj
Discovered Mono file path: /Library/Frameworks/Mono.framework/Versions/Current/Commands/mono
Resolved symbolic link for Mono file path: /Library/Frameworks/Mono.framework/Versions/5.0.1/bin/mono-sgen32
[info]: OmniSharp.MSBuild.MSBuildProjectSystem
        Loading project: /Users/breiter/src/wolfereiter/ifes-accounts-payable/Ifes.AccountsPayable.Web/Ifes.AccountsPayable.Web.csproj
[warn]: OmniSharp.MSBuild.MSBuildProjectSystem
        Failed to load project file '/Users/breiter/src/wolfereiter/ifes-accounts-payable/Ifes.AccountsPayable.Web/Ifes.AccountsPayable.Web.csproj'.
warn]: OmniSharp.MSBuild.MSBuildProjectSystem
        Failed to load project file '/Users/breiter/src/wolfereiter/ifes-accounts-payable/Ifes.AccountsPayable.Web/Ifes.AccountsPayable.Web.csproj'.
/Users/breiter/src/wolfereiter/ifes-accounts-payable/Ifes.AccountsPayable.Web/Ifes.AccountsPayable.Web.csproj(1,1)
Microsoft.Build.Exceptions.InvalidProjectFileException: The imported project "/Users/breiter/.vscode/extensions/ms-vscode.csharp-1.10.0/bin/xbuild/Microsoft/VisualStudio/v14.0/WebApplications/Microsoft.WebApplication.targets" was not found. Confirm that the path in the <Import> declaration is correct, and that the file exists on disk.  

The key issue is that the environment is resolving $(VSToolsPath)\WebApplications\Microsoft.WebApplication.targets as /Users/breiter/.vscode/extensions/ms-vscode.csharp-1.10.0/bin/xbuild/Microsoft/VisualStudio/v14.0/WebApplications/Microsoft.WebApplication.targets which does not exist because xbuild is not encluded in the ms-vscode.csharp-1.10.0/bin directory.

It does, however, exist on my system as part of the mono distribution bundled with Visual Studio for Mac in /Library/Frameworks/Mono.framework/Versions/Current/lib/mono/xbuild.

It doesn't help to set the "omnisharp.useMono": true option and I can't see a way to redefine the environment to look in my mono system install rather than the extension to find the .targets files.

Creating a symlink to embed the xbuild directory from mono into the extension resolves the problem:

ln -s  /Library/Frameworks/Mono.framework/Versions/Current/lib/mono/xbuild ~/.vscode/extensions/ms-vscode.csharp-1.10.0/bin

Possibly you need to bundle the xbuild directory that mono ships with on macOS and Linux as a dependency for this extension or else have the environment detect that the xbuild directory is in a canonical location and use it.

[DustinCampbell]

Thanks for the report! We still need to do work in omnisharp-roslyn to properly map the tools path in VS for Mac.

Note: setting "omnisharp.useMono" won't do anything for this scenario. That setting is for when you're using a custom OmniSharp build with C# for VS Code.

[DustinCampbell]

So far, I've been unsuccessful creating a Web Application project with VS for Mac that doesn't work in VS Code. Is there some specific way I should create a Web Application project?

[breiter]

The projects I have tried were originally created with Visual Studio 2010 and 2013 and have rolled forward to being maintained with Visual Studio 2015 and 2017.

[DustinCampbell]

I've got a fix for this in PR here: OmniSharp/omnisharp-roslyn#923. Once it's merged, it'll appear in C# for VS Code once we take a new version of OmniSharp.