fix(getWeekView): use correct height for events on days where DST changes

Closes mattlewis92/angular-calendar#1348

Author: mattlewis92

src/calendar-utils.ts

@@ -1002,7 +1002,11 @@ function getDayView(
 
       const startDate: Date = startsBeforeDay ? startOfView : eventStart;
       const endDate: Date = endsAfterDay ? endOfView : eventEnd;
-      let height: number = differenceInMinutes(endDate, startDate);
+      const timezoneOffset =
+        startDate.getTimezoneOffset() - endDate.getTimezoneOffset();
+      let height: number =
+        differenceInMinutes(endDate, startDate) + timezoneOffset;
+
       if (!event.end) {
         height = segmentHeight;
       } else {

test/calendar-utils-dst.spec.ts

@@ -1,6 +1,7 @@
 import './util/use-london-timezone';
 import { getWeekView } from '../src/calendar-utils';
 import { adapterFactory as dateFnsAdapterFactory } from '../src/date-adapters/date-fns';
+import { startOfDay } from 'date-fns';
 
 const dateAdapter = dateFnsAdapterFactory();
 
@@ -30,4 +31,23 @@ describe('getWeekView', () => {
     expect(result.hourColumns[0].hours.length).toEqual(24);
     expect(result).toMatchSnapshot();
   });
+
+  it('should get the correct week height on days where DST changes', () => {
+    const result = getWeekView(dateAdapter, {
+      viewDate: new Date('2020-10-25'),
+      hourSegments: 2,
+      dayStart: { hour: 0, minute: 0 },
+      dayEnd: { hour: 23, minute: 59 },
+      segmentHeight: 30,
+      weekStartsOn: 0,
+      events: [
+        {
+          title: '',
+          start: startOfDay(new Date('2020-10-25')),
+          end: startOfDay(new Date('2020-10-26')),
+        },
+      ],
+    });
+    expect(result.hourColumns[0].events[0].height).toEqual(1439);
+  });
 });