Why jest fails with "component is part of the declaration of 2 modules"?

Question

I'm getting the following exception within executing a test in an angular (nx) project:

Error: Type FooComponent is part of the declarations of 2 modules: FooComponentModule and FooComponentModule! Please consider moving FooComponent to a higher module that imports FooComponentModule and FooComponentModule. You can also create a new NgModule that exports and includes FooComponent then import that NgModule in FooComponentModule and FooComponentModule.

The thing is I'm getting this exception only in IntelliJ (2022.3.1, MacOS) when I use the build-in jest integration. A colleague with Windows is getting this exception everywhere.

I was trying to execute the test app.component.spec.ts in my test project . The test should be executed successfully – everywhere not only in the CLI. The craziest thing is: I copied the command IntelliJ is executing within the build-in jest integration to the build-in terminal and it just works

I'm really unsure where to address this issue. Is this an issue with jest? Angular? NX? IntelliJ?

Update:

It seems to be an nx related issue. I created a simple clean angular project with jest and the same prerequisites (like lib, path aliases) and everything worked as expected.

Update 2:

I created an issue in the nx repo: https://github.com/nrwl/nx/issues/14494

Answer 1

It's not really the solution of the main problem but to use standalone components instead of SCAM Components would help and avoid the exception.