Bring back spy.reset()

[AdamMcCormick]

A previous issue #27 introduced the reset method to this library which we use extensively. It was removed in 1.0 for no clear reason. I'd like to see it put back

[dabutvin]

@AdamMcCormick can you use restore instead?

chai.spy.restore()

[AdamMcCormick]

@dabutvin No. Please see the thread at #27. Restore is not the same thing and does not satisfy my use case. It also makes my tests significantly slower given my test setup.

[zinoadidi]

Any update on this issue?

[keithamus]

Hey @AdamMcCormick thanks for the issue.

It was removed as it was seen to be an anti pattern because it swaps out internal state which can cause issues in tests - certainly compounding issues if your tests rely on external state. The preferred alternative is to restore and make a new spy.

@AdamMcCormick could you please give us some numbers as to how much slower your tests are by using restore? I'd be surprised to see even 100ms delta between restore/reset.

[jorgeortega]

You can just do

const spy = () => chai.spy()
let funcToBeSpied

beforeEach(() => {
  funcToBeSpied = spy()
})

[Daghall]

With proxyquire you have to clear the require cache and re-proxyquire the module, in order to do a full reset.
That is quite messy. This was my solution for resetting the spy, in lieu of spy.reset():

let barSpy;
const foo = proxyquire("../lib/foo.js", {
  "./bar.js": (...args) => barSpy(...args),
});

describe("foo bar", () => {
  beforeEach(() => {
    barSpy = chai.spy();
  });

  it("bar is called once by foo", () => {
    foo();
    expect(barSpy).to.have.been.called.once;
  });

  it("bar is called once by foo, again", () => {
    foo();
    expect(barSpy).to.have.been.called.once;
  });
});