Content + PublishFolderType do not copy file in the app bundle in Release configuration

[snechaev]

Apple platform

macOS

Framework version

net10.0-*

Affected platform version

.net 10.0.201, macos workload 26.2.10217/10.0.100

Description

I'm trying to copy test.txt as a resource into the app bundle. I use the following in my csproj:

    <ItemGroup>
        <None Remove="test.txt"/>
        <Content Include="test.txt">
<!--            <CopyToOutputDirectory>Always</CopyToOutputDirectory>-->
            <PublishFolderType>Resource</PublishFolderType>
<!--            <Link>/Contents/Test123/test.txt</Link>-->
        </Content>
    </ItemGroup>

This works in Debug, but does not work in Release. No build errors, but also no test.txt in the output app bundle.

Steps to Reproduce

1. Get test project macOSApp1.zip.
   • this is just dotnet new macos with added test.txt and it's configuration as an bundle resource.
2. Build in debug and release: dotnet build && dotnet build -c Release
3. Check if the test.txt is present in the ouptput: find ./bin/ -name "test.txt"

Expected: test.txt is found in both Debug and Release app bundles.
Actual: test.txt is found only in Debug

~/work/macOSApp1/macOSApp1$ find ./bin/ -name "test.txt"
./bin/Debug/net10.0-macos/osx-arm64/macOSApp1.app/Contents/Resources/test.txt

Did you find any workaround?

No response

Build logs

Release & Debug logs: binlogs.zip

[snechaev]

Also tried this on net8.0 (with global.json + changed tfm): .net 8.0.419, macos workload 15.0.8319/8.0.100 and got even more wierd results:

• fresh build (after deleting bin, obj) - test.txt presented only in Debug, the same thing as for net10
• non-fresh build (just run dotnet build && dotnet build -c Release again without any cleanup) - test.txt now presented in both Debug and Release.

//✅ cleanup
sergey@Sergeys-Mini macOSApp1 % rm -rf ./bin ./obj                                                                                                                        

//✅ first (fresh) build
sergey@Sergeys-Mini macOSApp1 % dotnet build && dotnet build -c Release
  Determining projects to restore...
  Restored /Users/sergey/work/macOSApp1/macOSApp1/macOSApp1.csproj (in 123 ms).
  Detected signing identity:
          
    Bundle Id: com.companyname.macOSApp1
    App Id: com.companyname.macOSApp1
  macOSApp1 -> /Users/sergey/work/macOSApp1/macOSApp1/bin/Debug/net8.0-macos/osx-arm64/macOSApp1.dll
  Optimizing assemblies for size may change the behavior of the app. Be sure to test after publishing. See: https://aka.ms/dotnet-illink
  Optimizing assemblies for size. This process might take a while.

Build succeeded.
    0 Warning(s)
    0 Error(s)

Time Elapsed 00:00:06.37
  Determining projects to restore...
  Restored /Users/sergey/work/macOSApp1/macOSApp1/macOSApp1.csproj (in 115 ms).
  Detected signing identity:
          
    Bundle Id: com.companyname.macOSApp1
    App Id: com.companyname.macOSApp1
  Detected signing identity:
          
    Bundle Id: com.companyname.macOSApp1
    App Id: com.companyname.macOSApp1
  macOSApp1 -> /Users/sergey/work/macOSApp1/macOSApp1/bin/Release/net8.0-macos/osx-x64/macOSApp1.dll
  Optimizing assemblies for size may change the behavior of the app. Be sure to test after publishing. See: https://aka.ms/dotnet-illink
  Optimizing assemblies for size. This process might take a while.
  Detected signing identity:
          
    Bundle Id: com.companyname.macOSApp1
    App Id: com.companyname.macOSApp1
  macOSApp1 -> /Users/sergey/work/macOSApp1/macOSApp1/bin/Release/net8.0-macos/osx-arm64/macOSApp1.dll
  Optimizing assemblies for size may change the behavior of the app. Be sure to test after publishing. See: https://aka.ms/dotnet-illink
  Optimizing assemblies for size. This process might take a while.

Build succeeded.
    0 Warning(s)
    0 Error(s)

Time Elapsed 00:00:12.44

//✅ checking results after fresh build
sergey@Sergeys-Mini macOSApp1 % find ./bin/ -name "test.txt"           
./bin/Debug/net8.0-macos/osx-arm64/macOSApp1.app/Contents/Resources/test.txt

//✅ second build (without cleanup)
sergey@Sergeys-Mini macOSApp1 % dotnet build && dotnet build -c Release
  Determining projects to restore...
  Restored /Users/sergey/work/macOSApp1/macOSApp1/macOSApp1.csproj (in 116 ms).
  Detected signing identity:
          
    Bundle Id: com.companyname.macOSApp1
    App Id: com.companyname.macOSApp1
  macOSApp1 -> /Users/sergey/work/macOSApp1/macOSApp1/bin/Debug/net8.0-macos/osx-arm64/macOSApp1.dll
  Optimizing assemblies for size may change the behavior of the app. Be sure to test after publishing. See: https://aka.ms/dotnet-illink
  Optimizing assemblies for size. This process might take a while.

Build succeeded.
    0 Warning(s)
    0 Error(s)

Time Elapsed 00:00:03.69
  Determining projects to restore...
  Restored /Users/sergey/work/macOSApp1/macOSApp1/macOSApp1.csproj (in 113 ms).
  Detected signing identity:
          
    Bundle Id: com.companyname.macOSApp1
    App Id: com.companyname.macOSApp1
  Detected signing identity:
          
    Bundle Id: com.companyname.macOSApp1
    App Id: com.companyname.macOSApp1
  macOSApp1 -> /Users/sergey/work/macOSApp1/macOSApp1/bin/Release/net8.0-macos/osx-x64/macOSApp1.dll
  Optimizing assemblies for size may change the behavior of the app. Be sure to test after publishing. See: https://aka.ms/dotnet-illink
  Optimizing assemblies for size. This process might take a while.
  Detected signing identity:
          
    Bundle Id: com.companyname.macOSApp1
    App Id: com.companyname.macOSApp1
  macOSApp1 -> /Users/sergey/work/macOSApp1/macOSApp1/bin/Release/net8.0-macos/osx-arm64/macOSApp1.dll
  Optimizing assemblies for size may change the behavior of the app. Be sure to test after publishing. See: https://aka.ms/dotnet-illink
  Optimizing assemblies for size. This process might take a while.

Build succeeded.
    0 Warning(s)
    0 Error(s)

Time Elapsed 00:00:09.69

//✅ checking results of the second build
sergey@Sergeys-Mini macOSApp1 % find ./bin/ -name "test.txt"           
./bin/Release/net8.0-macos/osx-x64/macOSApp1.app/Contents/Resources/test.txt
./bin/Release/net8.0-macos/macOSApp1.app/Contents/Resources/test.txt
./bin/Release/net8.0-macos/osx-arm64/macOSApp1.app/Contents/Resources/test.txt
./bin/Debug/net8.0-macos/osx-arm64/macOSApp1.app/Contents/Resources/test.txt

[rolfbjarne]

Thanks for the report!

I can reproduce the problem, it's got something to do with building a universal app bundle, where we build one app bundle for each architecture (arm64+x64), and then merge the results, and some resources seem to get lost in the process.

This explains the Debug/Release difference: release builds are by default universal, while debug builds are only building for the current architecture.

One potential workaround would be to only build for arm64, if you know you're not going to run on x64 machines, by adding this to your csproj:

<PropertyGroup>
    <RuntimeIdentifier>osx-arm64</RuntimeIdentifier>
</PropertyGroup>

Another option would be to use @(BundleResource) instead of @(Content):

<ItemGroup>
    <BundleResource Include="test.txt" />
</ItemGroup>