Test integration can hang UI indefinitely on large files

[dgshep]

When invoking "run all tests in ns" on a large test file (3k lines) the UI eventually hangs. I managed to attach yourkit to see what was going on and have attached the offending thread tree:

cursive-perf.gz

I've not waited long enough to see if it eventually unhangs, but it was in this state for multiple minutes before I gave up