brjs-clock

brjs-clock

brjs-clock is a library that provides a Clock class that allows to control the flow of time for a testing environment.

Installation

To install brjs-clock use:

npm install brjs-clock

Code Example

'use strict';

var clock = require('brjs-clock');
var expect = require('expectations');

describe('Clock', function() {
    var timeoutCounter, intervalCounter;

    beforeEach(function() {
        clock = new Clock();
        clock.install();

        timeoutCounter = 0;
        intervalCounter = 0;

        setTimeout(function() {
            timeoutCounter++;
        }, 1000);

        setInterval(function() {
            intervalCounter++;
        }, 2000);
    });

    afterEach(function() {
        clock.uninstall();
    });

    it('fires the timer only once', function() {
        clock.tick(999);
        expect(timeoutCounter).toBe(0);
        clock.tick(1);
        expect(timeoutCounter).toBe(1);
        clock.tick(1000);
        expect(timeoutCounter).toBe(1);
    });

    it('fires at each interval', function() {
        clock.tick(2000);
        expect(intervalCounter).toBe(1);
        clock.tick(2000);
        expect(intervalCounter).toBe(2);
    });
});