Setting IncludePackageReferencesDuringMarkupCompilation with a custom BaseIntermediateOutputPath causes build to fail

[nick-beer]

• .NET Core Version: 5.0.102

Problem description:
I tried following the suggestion in #3963 in order to pull in a source generator nuget to a wpf project. Upon doing so (setting IncludePackageReferencesDuringMarkupCompilation to true), my build fails with the following:

C:\Program Files\dotnet\sdk\5.0.102\Sdks\Microsoft.NET.Sdk\targets\Microsoft.PackageDependencyResolution.targets(241,5):
error NETSDK1004: Assets file 'C:\Dev\pkgref-bugs\Objects\wpf-app_smqwgw3w_wpftmp\project.assets.json' not found.
Run a NuGet package restore to generate this file. [C:\Dev\pkgref-bugs\wpf-app\wpf-app_smqwgw3w_wpftmp.csproj]

I noticed that if I stop using a custom BaseIntermediateOutputPath for my projects, then I'm able to build successfully.

Expected behavior:
I should be able to use source generators with wpf applications and use a custom BaseIntermediateOutputPath

Minimal repro:

• Add a package reference to a source generator in a wpf project
• Set the IncludePackageReferencesDuringMarkupCompilation property to be true
• Create a Directory.Build.props file to set BaseIntermediateOutputPath. I used ..\Objects\$(MSBuildProjectName)

[ryalanms]

Hi @nick-beer

#4009

Apologies for the messaging on this feature. The path changes were separated from the source generator support to meet the risk bar for 5.0.2 servicing, but were added back as an opt-in feature for 5.0.3. The changes are in master and will be in 5.0.3 when it ships. Thanks.

[nick-beer]

@ryalanms - thanks for the information. I'll be looking forward to 5.0.3.

Glad to hear it won't matter long term, but in the meantime I was able to move forward by making the intermediate output path for the WPF inner build match that of the standard build.

<IsWpfInnerTempProject Condition="$(MSBuildProjectName.EndsWith('_wpftmp'))">true</IsWpfInnerTempProject>
<BasePathProjectName>$(MSBuildProjectName)</BasePathProjectName>
<BasePathProjectName Condition="'$(IsWpfInnerTempProject)' == 'true'">$([System.Text.RegularExpressions.Regex]::Replace($(MSBuildProjectName), '_[^_]+_wpftmp', '', System.Text.RegularExpressions.RegexOptions.IgnoreCase))</BasePathProjectName>
<BaseIntermediateOutputPath>$(ObjectDirectory)\NetCore\$(BasePathProjectName)</BaseIntermediateOutputPath>

[ryalanms]

Please reactivate if you see any issues with 5.0.3. Thanks.

[nick-beer]

@ryalanms - I'm still seeing this with sdk 5.0.201, but I'm not able to reopen this issue.

I've created a simple set of projects that reproduce the issue - you can get it here.