Turn on testing then add tests - patch attached!

Adjust schema to allow for successful entity creation within tests.
Add coverage for entity list builder extension.

Can the project maintainer(s) please enable testing for this project? Thanks!

https://www.drupal.org/node/1449736

Testing is very important, and should be turned on even if there are no tests because testing will still catch syntax errors and coding standards and things like that. Plus it will allow patches like this to be tested!

Just a few notes:

You should set the issue status to "Needs review" when you post a patch - that way people know there's something to look at.

Your test should define
protected $defaultTheme = 'stark';
See https://www.drupal.org/node/3083055
While this is not strictly needed at present, it becomes mandatory in D9, can be used in D8.8, and is ignored in previous versions of D8 core. Better to do it correctly now rather than to have to go back and fix this in the future.

I assume the changes to schema.yml are there because the test fails the strict schema check without those changes? If so, this is an even stronger reason to turn on testing and commit this patch!

@TR - I was going to hold off on moving the issue to NR until the test runner reported green.

You are correct about the schema yaml changes.

Great call on the new $defaultTheme property! I forgot about that because my local test runner was set up to ignore deprecations (carry over from another project).

I think this issue can be closed? It would also be nice to have a D9 test configured to run weekly so we could make sure this module stays functioning going forward.