Imported NuGet .targets causes additional project platforms to be displayed

[sgarske]

Description

After installing the Microsoft.Web.Webview2 NuGet package onto a C# class library (.NET Framework) project, Visual Studio will display additional project platforms that are not defined in the .csproj.

Default project platforms after creating project

After installing NuGet package

Version
SDK: At least 1.0.705.50 of Microsoft.Web.Webview2 NuGet package or later (also confirmed with 1.0.1018-prerelease )
Runtime: N/A?
Framework: Confirmed with a WPF application project/solution and a C# Wix Custom Action library
OS: Win10

Repro Steps

1. Create a new C# Class Library (.NET Framework) project
2. Install latest Microsoft.Web.Webview2 NuGet package
3. Close/re-open solution
4. View the detected "Platforms" in the project properties

I expected no additional Platforms to show besides what are defined by my project. By installing the package and the import of the .targets, additional platforms show.

Additional context

I believe this has to do with the setting of EffectivePlatform at the beginning of Common.targets ( automatically imported by Microsoft.Web.WebView2.targets )

<?xml version="1.0"?>
<Project ToolsVersion="12.0" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
  <!-- The Platform property is Win32 or x64 for C++ projects. Convert from Win32 to x86 to match our directory structure.
    If PlatformTarget property is set, then use that to determine EffectivePlatform for .NET projects.
    See conditions: https://docs.microsoft.com/en-us/visualstudio/msbuild/msbuild-conditions?view=vs-2019
    and PropertyGroup: https://docs.microsoft.com/en-us/visualstudio/msbuild/propertygroup-element-msbuild?view=vs-2019
  -->
  <PropertyGroup>
    <EffectivePlatform>$(Platform)</EffectivePlatform>
    <EffectivePlatform Condition="'$(Platform)' == 'Win32'">x86</EffectivePlatform>
    <EffectivePlatform Condition="'$(Platform)' == 'Any CPU'">x86</EffectivePlatform>
    <EffectivePlatform Condition="'$(Platform)' == 'AnyCPU'">x86</EffectivePlatform>
...

I believe by just checking for conditional platforms that don't exist in the project, it triggers the project UI to show them as possible options. This causes confusion of which platforms are actually available.

I removed these lines and the issue went away.

Honestly, it feels like it may be an issue with Visual Studio and the project structure, but maybe that's just how it works? Possibly the NuGet targets can add a conditional to the whole PropertyGroup since it's not even needed in the .NET project case.

Thanks for reading/considering.

AB#36410393

[champnic]

Thanks for the bug report @sgarske! I've added it to our backlog. It is surprising that Visual Studio would be so proactive about adding platforms based on a condition check!

[jhennessey]

Can confirm this is still an issue today.

Simply using $(EffectivePlatform) instead of $(Platform) in the conditions (since it already has the Platform value) should fix this issue. You could also just copy the value of $(Platform) to a temporary property as well.

So this code:

  <PropertyGroup>
    <EffectivePlatform>$(Platform)</EffectivePlatform>
    <EffectivePlatform Condition="'$(Platform)' == 'Win32'">x86</EffectivePlatform>
    <EffectivePlatform Condition="'$(Platform)' == 'Any CPU'">x86</EffectivePlatform>
    <EffectivePlatform Condition="'$(Platform)' == 'AnyCPU'">x86</EffectivePlatform>

Becomes either this:

  <PropertyGroup>
    <EffectivePlatform>$(Platform)</EffectivePlatform>
    <EffectivePlatform Condition="'$(EffectivePlatform)' == 'Win32'">x86</EffectivePlatform>
    <EffectivePlatform Condition="'$(EffectivePlatform)' == 'Any CPU'">x86</EffectivePlatform>
    <EffectivePlatform Condition="'$(EffectivePlatform)' == 'AnyCPU'">x86</EffectivePlatform>
...

Or this:

  <PropertyGroup>
    <CurrentPlatform>$(Platform)</CurrentPlatform>
    <EffectivePlatform>$(CurrentPlatform)</EffectivePlatform>
    <EffectivePlatform Condition="'$(CurrentPlatform)' == 'Win32'">x86</EffectivePlatform>
    <EffectivePlatform Condition="'$(CurrentPlatform)' == 'Any CPU'">x86</EffectivePlatform>
    <EffectivePlatform Condition="'$(CurrentPlatform)' == 'AnyCPU'">x86</EffectivePlatform>
...

Would love to see this fixed soon as it causes a headache for tools that parse projects via the MSBuild API.

My current use case is writing a tool to automatically update legacy csproj files and add a Platforms property that contains all valid platforms for the project. This is required in order to make use of the SetPlatform Negotiation feature in MSBuild. Right now, all projects referencing this package end up with invalid platforms.

[champnic]

I've just put in a quick fix for this. I think it just missed the cutoff for the next prerelease SDK, but should be available in the following one.