Visual Studio SvcUtil integration uses xmlparse to read properties where they should be evaluated

[MeikTranel]

Describe the bug
When using property references to control the target framework of a project, svcutils reads the msbuild syntax instead of the actual value crashing the update servicereference option in Visual Studio 2019 16.10.2.

svcutil should use either use MSBuild evaluation libraries or receive the values from Visual Studio as parameters. XML parsed values are super suboptimal alltogether - with the advent of Directory.Build.props etc. lots of projects depend on evaluation to really a get the actual picture of references, properties and such.

To Reproduce

./Directory.Build.props

<Project>
  <PropertyGroup>
    <DefaultTFM>net452</DefaultTFM>
  </PropertyGroup>
  <ItemGroup>
    <Reference Include="./SampleLib.dll" />
  </ItemGroup>
</Project>

./Client/Client.csproj

<Project Sdk="Microsoft.Net.Sdk">
  <PropertyGroup>
    <TargetFramework>$(DefaultTFM)</TargetFramework>
  </PropertyGroup>
</Project>

Expected behavior
svcutil picks up net452 as the designed targetframework for code generation.

stretch-goal: svcutil picks up SampleLib.dll as a designated reference to reuse types from.

Screenshots

Additional context
A friendly aussie wizard dropped by and found the root cause: https://twitter.com/davkean/status/1410532553530875904

[HongGit]

@imcarolwang can you please try to see if this is a regression from .NET framework tools, svcutil?

[KalleOlaviNiemitalo]

can you please try to see if this is a regression from .NET framework tools, svcutil?

This is a regression, in the sense that svcutil does not access the MSBuild project file at all and thus won't be confused by any TargetFramework setting in there.

A workaround of sorts:

<PropertyGroup>
  <TargetFramework>$(DefaultTFM)</TargetFramework>

  <!-- dotnet-svcutil reads the last TargetFramework and ignores Condition -->
  <TargetFramework Condition="0 != 0">net45</TargetFramework>
</PropertyGroup>