After much digging as to why my tests are timing out even though running directly was always fine... I found out that TestRunner's coverageRun is using #valueUnpreemptively to run all tests.
The problem is that one of the tests is retrieving something over network, and that apparently doesn't go well together.
This works
[ (ZnEasy get: 'http://example.com') entity contents ] value
This freezes the image forever and runs a CPU core at 100%
Is there some resolution to this?
Thanks,
Peter