Added two new functions dateroll and datediff

lib/date.js

@@ -1,4 +1,7 @@
 'use strict';
+
+const { date } = require('.');
+
 var helpers = module.exports;
 
 /**
@@ -22,3 +25,83 @@ helpers.year = require('year');
  */
 
 helpers.moment = helpers.date = require('helper-date');
+
+helpers.ONE_SEC = 1000;
+helpers.ONE_MIN = helpers.ONE_SEC * 60;
+helpers.ONE_HOUR = helpers.ONE_MIN * 60;
+helpers.ONE_DAY = helpers.ONE_HOUR * 24;
+helpers.ONE_YEAR = helpers.ONE_DAY * 365;
+
+
+helpers.dateroll = function(date1, nUnit, unit, format) {
+ var dateStart = null;
+
+ if ( date1 instanceof Date) {
+ dateStart = date1;
+ } else if ( typeof (date1) === 'string') {
+ dateStart = new Date(date1);
+ }
+
+ var time = dateStart.getTime();
+ var delta = 0;
+
+ if ( unit === 'year' ) {
+ delta = nUnit * helpers.ONE_YEAR;
+ } else if ( unit === 'day' ) {
+ delta = nUnit * helpers.ONE_DAY;
+ } else if ( unit === 'hour' ) {
+ delta = nUnit * helpers.ONE_HOUR;
+ } else if ( unit === 'minute' ) {
+ delta = nUnit * helpers.ONE_MIN;
+ } else if ( unit === 'second' ) {
+ delta = nUnit * helpers.ONE_SEC;
+ }
+
+ time = time + delta;
+
+ var d = new Date();
+ d.setTime(time);
+
+ var formattedDate = '';
+
+ if ( typeof (format) === 'string' && format ) {
+ formattedDate = format.replace('yyyy', d.getUTCFullYear()).replace('MM', ('0'+(d.getUTCMonth()+1)).slice(-2)).replace('dd', ('0' + d.getUTCDate()).slice(-2))
+ } else {
+ formattedDate = + d.getUTCFullYear() + '-' + ('0'+(d.getUTCMonth()+1)).slice(-2) + '-' +
+ ('0' + d.getUTCDate()).slice(-2);
+ }
+
+ return formattedDate;
+};
+
+helpers.datediff = function(date1, date2, unit) {
+ let dateFrom= null;
+ let dateTo = null; 
+ if ( date1 instanceof Date ) {
+ dateFrom = date1 ;
+ } else if ( typeof (date1) === 'string' ) {
+ dateFrom = new Date(date1);
+ }
+
+ if ( date2 instanceof Date ) {
+ dateTo = date2 ;
+ } else if (typeof (date2) === 'string') {
+ dateTo = new Date(date2);
+ }
+
+ var delta = dateTo.getTime() - dateFrom.getTime();
+
+ if ( unit === 'year' ) {
+ return delta / helpers.ONE_YEAR;
+ } else if ( unit === 'day') {
+ return delta / helpers.ONE_DAY;
+ } else if ( unit === 'hour') {
+ return delta / helpers.ONE_HOUR;
+ } else if ( unit === 'minute') {
+ return delta / helpers.ONE_MIN;
+ } else if ( unit === 'second') {
+ return delta / helpers.ONE_SEC;
+ } else {
+ return delta / helpers.ONE_DAY;
+ }
+};

test/date.js

@@ -0,0 +1,29 @@
+'use strict';
+
+require('mocha');
+var assert = require('assert');
+var hbs = require('handlebars').create();
+var helpers = require('..');
+helpers.date({handlebars: hbs});
+
+describe('date', function() {
+ describe('datediff', function() {
+ describe('inline or subexpression', function() {
+ it('should return the difference of two numbers.', function() {
+ var fn = hbs.compile('{{datediff dateFrom dateTo unit}}');
+ var r = fn({dateFrom: '2022-01-01', dateTo: '2023-01-01', unit: 'year'});
+ console.log("Result: " + r);
+ assert.equal(r, '1');
+ });
+ });
+ });
+
+ describe('datedroll', function() {
+ describe('inline', function() {
+ it('should return the computed date.', function() {
+ var fn = hbs.compile('{{dateroll dateFrom nUnit unit}}');
+ assert.equal(fn({dateFrom: '2022-01-01', nUnit: 365, unit: 'day', format: 'yyyy-MM-dd'}), '2023-01-01');
+ });
+ });
+ });
+});