WebTest: Error: Invalid database prefix

Hi there,

since a few months, I’m developing a module which has some Test Cases which extend WebTestBase Class.

I didn’t run the tests for quite some time and also didn’t change anything inside the test cases or code which would affect test cases. But I did add quite a lot of configuration yml into my modules config/install folder.

Now if I want to execute a TestCase I get the following exception:

InvalidArgumentException: Invalid database prefix: in DrupalCoreTestTestDatabase->__construct() (line 81 of core/lib/Drupal/Core/Test/TestDatabase.php). 

I debugged it as far as I could go and it seems to be that my TestCase crashes at some point, leading to passing no information at all to the function which handles the batch result. _simpletest_batch_finished()

Neither Drupal Log nor PHP Log provide any other error message than the one I posted.

Did someone else ran into this problem at some point?
Or does someone has any advice how I could get more detailed information about the actual error and not the produced result?

regards, Lenny

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