This module mocks Date and Date.now in order to help you test time-dependent code. It provides travel and freeze functionality for your Node.js tests.

npm install --save-dev timekeeper

var tk = require('timekeeper');
var time = new Date(1330688329321);
tk.freeze(time);
// The time hasn't changed at all.
var date = new Date;
var ms = Date.now();
tk.reset(); // Reset.

var tk = require('timekeeper');
var time = new Date(1893448800000); // January 1, 2030 00:00:00
tk.travel(time); // Travel to that date.
setTimeout(function() {
  // `time` + ~500 ms.
  var date = new Date;
  var ms = Date.now();
  tk.reset(); // Reset.
}, 500);

Note: If traveling when time is frozen, the time will be frozen to the new traveled time.

var tk = require('timekeeper');
var time = new Date(1893448800000); // January 1, 2030 00:00:00
assertFalse(tk.isKeepingTime());
tk.travel(time);
assertTrue(tk.isKeepingTime());

Inspired by the timecop ruby gem.

MIT License

Copyright (C) 2012 Veselin Todorov Copyright (C) 2018, 2019, 2023 Linus Unnebäck

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.