Sinon stubs are not restored properly

Question

I am using mocha, chai and sinon to test my node-express code.

I am experiencing a weird issue, which looks like sinon cannot restore stubs and so in the next test I get the beknown error

Attempted to wrap <method1> which is already wrapped

Here is what I do

• I use mocha-steps instead of it() clause for my test cases, so that they run sequentially (I wanted to ensure it is not an async race condition)
  • I use sinon-test to clean up the stubs automatically, just in case I was doing something wrong

Here is a test case:

step('should do stuff', test(function () {

    const stub1 = sinon.stub(my_model1, 'method1');

    chai.request(server)
        .get('/endpoint')
        .send(body)
        .end(function (err, res) {
            stub1.restore();
            do_various_assertions(err, res);
        });
}));

And another one

step('should do other stuff', test(function () {

        const stub1 = sinon.stub(my_model1, 'method1');

        chai.request(server)
            .get('/endpoint')
            .send(slightly_different_body)
            .end(function (err, res) {
                stub1.restore();
                do_various_assertions(err, res);
            });
    }));

where I get the error above

Attempted to wrap <method1> which is already wrapped

If I comment out the stub in the second case works fine. But why? What am I doing wrong?

Answer 1

Next step should know that previous step has completed, you need to call done function. In your example second step doesn't wait first one and method1 isn't restored.

step('should do stuff', function (done) {

    const stub1 = sinon.stub(my_model1, 'method1');

    chai.request(server)
        .get('/endpoint')
        .send(body)
        .end(function (err, res) {
            stub1.restore();
            do_various_assertions(err, res);
            done();
        });
});