Sinon fails to uninstall clock when using jest.fakeTimers()

I am using both Sinon clock and jest.useFakeTimers for legacy reasons, and I am getting an error while trying to uninstall sinon clock: TypeError: _global.setInterval is not a function after enabling jest.useFakeTimers() during some test. I know that it’s a bit fucked up to use both sinon and jest.useFakeTimers, but anyways I think that sinon should handle this situation gracefully.

• FakeTimers version : 8.1.0
• Environment : node
• Example URL :
• Other libraries you are using: React native testing library, jest

What did you expect to happen? Sinon should be able to uninstall clock even after using jest.fakeTimers What actually happens Sinon throws exception when trying to uninstall clock after using jest.fakeTimers How to reproduce

1. install sinon clock:

  clock = FakeTimers.install({
    shouldAdvanceTime: true,
  });

1. use jest.fakeTimers()
2. try to uninstall clock.
3. TypeError: _global.setInterval is not a function

[SimenB]

26 (by default) uses its own implementation and the one using Lolex is opt-in via jest.useFakeTimere('modern'). In v27 “modern” is the default. Might also be a mismatch in version of Lolex of course

[SimenB]

Note that Jest ships with @sinonjs/fake-timers if you use “modern” fake timers (default in v27), and mixing them is not supported. You should use one or the other.