Parallel execution and ThreadLocal variables

[KptCheeseWhiz]

Context:
At my company, we are creating various cucumber files for our E2E testing. Every feature has a local database state that is wrapped by a ThreadLocal to make sure that a state is unique to every feature and only reused between screnarios if needed. Everything is working fine, but from time to time there are weird errors that are appearing linked to a state being reused between two features.

Question:
Are every cucumber feature always executed in a new thread or are threads reused? Here is the command we are using to run the tests:
mvn -Dtest=XXXX.Cucumbertests -Dparallel=methods -Dthreadcount=10 test

[mpkorstanje]

Threads are reused. How exactly will depend whether you use JUnit 4, JUnit 5 or TestNG.

To share state between steps within a single scenario, it is recommended that you use dependency injection. Cucumber will ensure that each scenario has its own isolated object graph to work on. As long as you don't use static variables, or leak your state into a shared context or external system that should work just fine,

• https://cucumber.io/docs/cucumber/state#dependency-injection
• https://github.com/cucumber/cucumber-jvm/tree/main/cucumber-picocontainer