This repository reproduces a bug that occurs when using jest to test a function that requires the bugsnag client.
To reproduce the bug simply run yarn test. You should see the error TypeError: setInterval(...).unref is not a function when the bugsnag client gets created.
This bug was seen when trying to integrate bugsnag into a react app and so there is a requirement for the jest testEnvironment to be the default jsdom rather than node. Part of the test requires window to be defined as a way of simulating this requirement.