Add help functions for ISO8601 date format

src/util/dates.js

@@ -169,3 +169,28 @@ export const formatDate = (intl, todayString, d) => {
 
   return `${formattedDate}, ${formattedTime}`;
 };
+
+/**
+ * Converts string given in ISO8601 format to date object.
+ * This is used e.g. when when dates are parsed form urlParams
+ *
+ * @param {String} dateString in 'YYYY-MM-DD'format
+ *
+ * @returns {Date} parsed date object
+ */
+export const parseDateFromISO8601 = dateString => {
+  return moment(dateString, 'YYYY-MM-DD').toDate();
+};
+
+/**
+ * Converts date to string ISO8601 format ('YYYY-MM-DD').
+ * This string is used e.g. in urlParam.
+ *
+ * @param {Date} date
+ *
+ * @returns {String} string in 'YYYY-MM-DD'format
+ */
+
+export const stringifyDateToISO8601 = date => {
+  return moment(date).format('YYYY-MM-DD');
+};

src/util/dates.test.js

@@ -1,5 +1,13 @@
 import { fakeIntl } from './test-data';
-import { isDate, isSameDate, nightsBetween, daysBetween, formatDate } from './dates';
+import {
+  isDate,
+  isSameDate,
+  nightsBetween,
+  daysBetween,
+  formatDate,
+  parseDateFromISO8601,
+  stringifyDateToISO8601,
+} from './dates';
 
 describe('date utils', () => {
   describe('isDate()', () => {
@@ -87,4 +95,19 @@ describe('date utils', () => {
       expect(formatDate(fakeIntl, 'Today', d)).toEqual('2017-11-22, 13:51');
     });
   });
+
+  describe('parseDateFromISO8601()', () => {
+    it('should return date', () => {
+      const dateString = '2018-11-23';
+      const date = new Date(2018, 10, 23);
+      expect(parseDateFromISO8601(dateString)).toEqual(date);
+    });
+  });
+
+  describe('stringifyDateToISO8601()', () => {
+    it('should return string in YYYY-MM-DD format', () => {
+      const date = new Date(2018, 10, 23);
+      expect(stringifyDateToISO8601(date)).toEqual('2018-11-23');
+    });
+  });
 });