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javascriptjasminejestjs

Disable Jest setTimeout mock

I'm writing a Jest test for code that depends on a websocket library.

The websocket library is mocked. I want to send a message, wait for async actions to complete, and check the response.

it('sends a message and gets a response', () => {
  processor(ws).sendMessage()  // do a bunch of async stuff, call websocket.sendMessage()
  setTimeout(() => {
    expect(ws.getResponse()).toEqual('all done')
  }, 100)
})

Unfortunately because Jest mocks setTimeout, setTimeout fails. If I run jest.runAllTimers(), the timeout happens instantaneously, so fails to pick up the message.

Any idea how to convince jest to unmock setTimeout, or a Jasmine workaround?

Solution

  • You can add following code before test cases. It works for me in Jest v14.1.0 - 

      jest.useRealTimers()