I\'m getting the following error when running the entire suite of tests:
timeout of 2000ms exceeded. Ensure the done() callback is being called in this test.
I don't see you cleaning up your mocked http backend. I have no idea how it functions, but I would expect that all your requests and responses are being stored in memory. That would cause it to increase gradually, test by test.
If this was using Sinon I would expect that you would create a stub/spy before the tests and clean it up afterwards (or run it in a sandbox).
Try taking a heap snapshot before and after running a test and diff the snapshots to find which objects keep increasing in numbers.