Bug: MSBuild doesn't build all variants

[applejag]

Expected behavior

Building with MSBuild either via dotnet build, MSBuild.exe, or via Visual Studio 2019 results in all the different DLLs used in the package:

/bin/Debug/unity-aot/Newtonsoft.Json.dll
/bin/Debug/unity-standalone/Newtonsoft.Json.dll
/bin/Debug/unity-editor/Newtonsoft.Json.dll
/bin/Debug/unity-portable/Newtonsoft.Json.dll
/bin/Debug/unity-tests/Newtonsoft.Json.dll

Actual behavior

Only some build. Sometimes it even takes multiple builds to get the most builds. But never the full list.

The missing build DLLs are:

/bin/Debug/unity-aot/Newtonsoft.Json.dll
/bin/Debug/unity-standalone/Newtonsoft.Json.dll

Steps to reproduce

• Clone repo
• Open solution /Src/Newtonsoft.Json.sln in Visual Studio 2019
• Start build Ctrl+B

Details

Host machine OS running Unity Editor 👉 Windows

Unity build target 👉 N/A

Newtonsoft.Json-for-Unity package version 👉 12.0.301

I was using Unity version 👉 N/A

Checklist

• [x] Shutdown Unity, deleted the /Library folder, opened project again in Unity, and problem still remains. (irrelevant)
• [x] Checked to be using latest version of the package.

[applejag]

Suggested solution is to abuse the MSBuild Batching feature.

I successfully did a small sample in the jilleJr/Newstonsoft.Json-for-Unity.Converters repo to target multiple files after a build (https://github.com/jilleJr/Newtonsoft.Json-for-Unity.Converters/blob/880c3d350f1eb3832d553dd0003e245df5b1e520/Src/Newtonsoft.Json.UnityConverters.Tests/Newtonsoft.Json.UnityConverters.Tests.csproj).

I wonder if the same technique can be applied to force multiple builds of the same target framework, as the AOT, Standalone, and Editor builds all use .NET Standard 2.0.

[applejag]

Nah abusing the Platform targets seems much more appropriate. There should be no harm in defining a platform for AOT, one for Standalone, one for Editor, etc. Then rely on the "Batch Build" feature to build them all. Links:

• MSDN: How to: Configure projects to target multiple platforms
• MSDN: How to: Build multiple configurations simultaneously
• StackOverflow: How do I specify the platform for MSBuild?

To fix the TargetFramework issue, maybe that could be resolved with having platform-specific target frameworks? Something like:

<Project Sdk="Microsoft.NET.Sdk">

  <Choose>
    <When Condition="'$(Platform)'=='Tests'">
      <PropertyGroup>
        <TargetFramework>net46</TargetFramework>
      </PropertyGroup>
    </When>
    <When Condition="'$(Platform)'=='Portable'">
      <PropertyGroup>
        <TargetFramework>portable-net45+win8+wpa81+wp8</TargetFramework>
      </PropertyGroup>
    </When>
    <Otherwise>
      <PropertyGroup>
        <TargetFramework>netstandard2.0</TargetFramework>
      </PropertyGroup>
    </Otherwise>
  </Choose>

</Project>

(MSDN on the <Choose> element: https://docs.microsoft.com/en-us/visualstudio/msbuild/choose-element-msbuild?view=vs-2019)