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reactjssinonsinon-chai

How to put a spy on clearInterval() in sinon?

I want to test that clearInterval() has been called on componentWillUnmount(). How do I set a spy on clearInterval()?

it("should unmount", () => {
    const wrapper = shallow(<MessageLoaderWrapper messageList={messageList} />);
    wrapper.unmount();
    expect(wrapper.find(".tabs-infinite-loader--message").length).to.equal(0);
});

Currently testing that a className is no longer there; but really should be testing that clearInterval() was called.

Solution

  • Global functions can be spied on window or global, depending on the environment, e.g.:

    sinon.spy(global, 'clearInterval');
...
expect(clearInterval).to.have.been.calledOnce;