scala - How to turn off parallel execution of tests for multi-project builds?

Question

I have a multi-project build with tests in sub-projects and in a parent project. The build is aggregated so that the parent project runs all tests in child projects.

I configured it so that there's no parallel execution of tests in both the sub-projects and the parent project, via

parallelExecution in Test := false

However, I have the nagging feeling that tests that span over multiple projects are ran in parallel. In the case of one of the sub-projects this is a problem because it mutates state in a test database concurrently, leading to the test to fail.

Any ideas as to how to globally switch of parallel execution of tests, between projects?

Answer 1

I think you can apply a setting across projects using scope ThisBuild, like

parallelExecution in ThisBuild := false

I don't know if you can combine that with scope Test, but it might not be necessary.