How do I stub new Date() using sinon?
sinon.useFakeTimers()
was breaking some of my tests for some reason, I had to stub Date.now()
sinon.stub(Date, 'now').returns(now);
In that case in the code instead of const now = new Date();
you can do
const now = new Date(Date.now());
Or consider option of using moment library for date related stuff. Stubbing moment is easy.
I found this question when i was looking to solution how to mock Date
constructor ONLY.
I wanted to use same date on every test but to avoid mocking setTimeout
.
Sinon is using [lolex][1] internally
Mine solution is to provide object as parameter to sinon:
let clock;
before(() => {
clock = sinon.useFakeTimers({
now: new Date(2019, 1, 1, 0, 0),
shouldAdvanceTime: true,
toFake: ["Date"],
});
})
after(() => {
clock.restore();
})
Other possible parameters you can find in [lolex][1] API [1]: https://github.com/sinonjs/lolex#api-reference
I suspect you want the useFakeTimers
function:
var now = new Date();
var clock = sinon.useFakeTimers(now.getTime());
//assertions
clock.restore();
This is plain JS. A working TypeScript/JavaScript example:
var now = new Date();
beforeEach(() => {
sandbox = sinon.sandbox.create();
clock = sinon.useFakeTimers(now.getTime());
});
afterEach(() => {
sandbox.restore();
clock.restore();
});