zurvan/tests/TimeUnitComparisonTests.js

A library for simulating time in Node.js

'use strict';
var TimeUnit = require('../TimeUnit');
var zurvan = require('../zurvan');

var assert = require('assert');

describe('TimeUnit', function() {
  it('can be compared in standard ways', function(done) {
    var hour = TimeUnit.hours(1);
    var threeQuarters = TimeUnit.minutes(45);

    assert(hour.isLongerThan(threeQuarters));
    assert(!hour.isShorterThan(threeQuarters));
    assert(!hour.isEqualTo(threeQuarters));
    assert(threeQuarters.isShorterThan(hour));
    assert(!threeQuarters.isLongerThan(hour));
    assert(!threeQuarters.isEqualTo(hour));

    done();
  });

  it('can be compared even if different units were used at first', function(done) {
    var month = TimeUnit.weeks(4);
    var monthInNanoseconds = TimeUnit.nanoseconds(1e9 * 60 * 60 * 24 * 7 * 4);

    assert(!month.isLongerThan(monthInNanoseconds));
    assert(!month.isShorterThan(monthInNanoseconds));
    assert(month.isEqualTo(monthInNanoseconds));

    assert(!monthInNanoseconds.isLongerThan(month));
    assert(!monthInNanoseconds.isShorterThan(month));
    assert(monthInNanoseconds.isEqualTo(month));

    done();
  });

  it('can be reliably compared even after calculations', function(done) {
    var hour = TimeUnit.hours(1);
    var quarter = TimeUnit.minutes(15);
    var hourInQuarters = quarter
      .extended(quarter)
      .extended(quarter)
      .extended(quarter);
    assert(
      hour.isEqualTo(
        quarter
          .extended(quarter)
          .extended(quarter)
          .extended(quarter)
      )
    );

    var second = TimeUnit.seconds(1);
    var quarterInSeconds = second.copy();

    var i;
    for (i = 0; i < 15 * 60; ++i) {
      quarterInSeconds.add(second);
    }

    assert(quarterInSeconds.isLongerThan(quarter));
    quarterInSeconds.subtract(TimeUnit.nanoseconds(1e9 - 1));
    assert(quarterInSeconds.isLongerThan(quarter));
    quarterInSeconds.subtract(TimeUnit.nanoseconds(1));
    assert(quarterInSeconds.isEqualTo(quarter));
    quarterInSeconds.subtract(TimeUnit.nanoseconds(1));
    assert(quarterInSeconds.isShorterThan(quarter));

    done();
  });

  it('is still reliable after many calculations', function(done) {
    var month = TimeUnit.weeks(4);
    var day = TimeUnit.days(1);
    var minute = TimeUnit.minutes(1);
    var second = TimeUnit.seconds(1);
    var nanosecond = TimeUnit.nanoseconds(1);

    var toIncrease = nanosecond.copy();
    var toDecrease = month.copy();

    var i;
    for (i = 0; i < 27; ++i) {
      toDecrease.subtract(day);
    }

    for (i = 0; i < 3600; ++i) {
      toIncrease.add(second);
    }

    for (i = 0; i < 12 * 60; ++i) {
      toDecrease.subtract(minute);
    }

    for (i = 0; i < 11 * 60; ++i) {
      toIncrease.add(minute);
    }

    assert(toIncrease.isLongerThan(toDecrease));
    assert(toDecrease.isShorterThan(toIncrease));
    toDecrease.add(nanosecond);
    assert(toIncrease.isEqualTo(toDecrease));
    assert(toDecrease.isEqualTo(toIncrease));
    toDecrease.add(nanosecond);
    assert(toIncrease.isShorterThan(toDecrease));
    assert(toDecrease.isLongerThan(toIncrease));

    done();
  });
});