TargetFramework cannot be set in Directory.Build.props

[Liversage]

Describe the bug

When <TargetFramework> is set in Directory.Build.props Stryker doesn't work.

Logs

I have a a solution folder with a Directory.Build.props that specifies <TargetFramework>net9.0</TargetFramework> and there are no <TargetFramework> in the .csproj files. The project to mutate and the unit test project are in subdirectories and the unit test project has a reference to the project to mutate. When executing dotnet stryker --verbosity debug in the unit test project I get the following console output:

[13:07:16 INF] Logging enabled at level Debug
Version: 4.4.1
[13:07:16 DBG] Stryker starting, version: 4.4.1

[13:07:16 DBG] Stryker started with options: [REMOVED FOR BREVITY]
[13:07:16 INF] Analysis starting.
[13:07:16 DBG] Using C:\Users\[REDACTED]\[REDACTED].UnitTests\[REDACTED].UnitTests.csproj as test project
[13:07:16 INF] Analyzing 1 test project(s).
[13:07:16 DBG] Analyzing 0 projects.
[13:07:16 DBG] Analyzing [REDACTED].UnitTests.csproj
[13:07:22 DBG] Analysis of project [REDACTED].UnitTests.csproj succeeded.
[13:07:23 DBG] Analyzing ..\[REDACTED]\[REDACTED].csproj
[13:07:29 DBG] Analysis of project ..\[REDACTED]\[REDACTED].csproj succeeded.
[13:07:29 INF] Analysis complete.
[13:07:29 INF] Time Elapsed 00:00:13.2623456
Stryker.NET failed to mutate your project. For more information see the logs below:


No project references found. Please add a project reference to your test project and retry.

Expected behavior

According to the logs Stryker correctly detects the project to mutate and should go ahead and perform the tests.

Adding <TargetFramework>net9.0</TargetFramework> to both .csproj files fixes the problem.

Desktop

• OS: Windows
• Type of project: "core"
• Framework Version: .NET 9.0
• Stryker Version: 4.4.1

Additional context

I haven't tried to locate the actual problem in the source code. Even if it's not worth fixing it might be helpful to explain this in the documentation. This is my first time using Stryker and it took me quite some time to understand why my project didn't work with Stryker despite following the clear and useful instructions in "Getting started".

[dupdob]

Thanks for raising this issue. We will look into it.
We may need more information if we fail to reproduce the problem.

Note that the issue may likely be within the Buildalyzer package Stryker uses for project analysis.

See phmonte/Buildalyzer#166

[Liversage]

@dupdob Yes, that's exactly the issue. The <TargetFramework> is not being picked up correctly so probably not something that can be fixed by this project.

[rouke-broersma]

Not sure what's going on here because we use this ourselves in Stryker: https://github.com/stryker-mutator/stryker-net/blob/master/src/Directory.Build.props#L4

[Liversage]

Not sure what's going on here because we use this ourselves in Stryker: https://github.com/stryker-mutator/stryker-net/blob/master/src/Directory.Build.props#L4

Perhaps <TargetFramework> is also set directly in the .csproj file or more likely the "fallback" <TargetFramework> used by Buildalyzer (I believe it's full framework) doesn't cause any compile errors. In my case I was using top-level statements and that didn't compile when using Stryker.

[dupdob]

Note that current Stryker releases do not support top-level statements....
This will be fixed in next release.