Fix 8-digit date suffix for Asara B'Tevet when timed calendar

package.json

@@ -1,6 +1,6 @@
 {
   "name": "@hebcal/core",
-  "version": "5.7.0",
+  "version": "5.7.1",
   "author": "Michael J. Radwin (https://github.com/mjradwin)",
   "contributors": [
     "Eyal Schachter (https://github.com/Scimonster)",

src/candles.ts

@@ -1,5 +1,5 @@
 /* eslint-disable max-len */
-import {HDate, months} from '@hebcal/hdate';
+import {HDate, months, isoDateString} from '@hebcal/hdate';
 import {CalOptions} from './CalOptions';
 import {Location} from './location';
 import {Event, flags} from './event';
@@ -86,6 +86,13 @@ export class FastDayEvent extends HolidayEvent {
     this.startEvent = startEvent;
     this.endEvent = endEvent;
   }
+  urlDateSuffix(): string {
+    if (this.getDesc() === "Asara B'Tevet") {
+      const isoDate = isoDateString(this.getDate().greg());
+      return isoDate.replace(/-/g, '');
+    }
+    return super.urlDateSuffix();
+  }
 }
 
 /**

test/candles.spec.ts

@@ -395,6 +395,27 @@ test('fastStartEnd-TzomTammuz', () => {
   expect(ev1.endEvent).toEqual(events[2]);
 });
 
+test('fastStartEnd Asara BTevet', () => {
+  const events0 = HebrewCalendar.calendar({
+    year: 2020,
+    location: Location.lookup('Providence'),
+    candlelighting: true,
+  });
+  const events = events0.filter((ev) => ev.getDesc() === 'Asara B\'Tevet');
+  expect(events.length).toBe(2);
+  expect(events[0]).toBeInstanceOf(FastDayEvent);
+  const urls = events.map((ev) => ev.url());
+  const expectedUrls = [
+    'https://www.hebcal.com/holidays/asara-btevet-20200107',
+    'https://www.hebcal.com/holidays/asara-btevet-20201225',
+  ];
+  expect(urls).toEqual(expectedUrls);
+  const fastEv = events[0] as FastDayEvent;
+  expect(fastEv.startEvent).toBeDefined();
+  expect(fastEv.startEvent).toBeInstanceOf(TimedEvent);
+  expect(fastEv.startEvent?.getDesc()).toBe('Fast begins');
+});
+
 test('fastStartEnd-withoutHoliday', () => {
   const events = HebrewCalendar.calendar({
     start: new Date(2021, 5, 27),