Determine Occurrence.Period by Duration only

Ical.Net.Tests/Calendars/Alarm/ALARM4.ics

@@ -8,7 +8,6 @@ DTSTAMP:20060717T210718Z
 UID:uuid1153170430406
 SUMMARY:Test event
 DTSTART;TZID=US-Eastern:19970902T090000
-DTEND;TZID=US-Eastern:19970902T100000
 EXDATE;TZID=US-Eastern:19970902T090000
 RRULE:FREQ=MONTHLY;BYDAY=FR;BYMONTHDAY=13
 BEGIN:VALARM

Ical.Net.Tests/Calendars/Alarm/ALARM6.ics

@@ -8,7 +8,6 @@ DTSTAMP:20060717T210718Z
 UID:uuid1153170430406
 SUMMARY:Test event
 DTSTART;TZID=US-Eastern:19970902T090000
-DTEND;TZID=US-Eastern:19970902T100000
 EXDATE;TZID=US-Eastern:19970902T090000
 RRULE:FREQ=MONTHLY;BYDAY=FR;BYMONTHDAY=13
 BEGIN:VALARM

Ical.Net.Tests/Calendars/Recurrence/DailyInterval1.ics

@@ -6,7 +6,6 @@ CREATED:20070405T013153Z
 DTEND;TZID=US-Eastern:20070410T070000
 DTSTAMP:20070405T013153Z
 DTSTART;TZID=US-Eastern:20070409T070000
-DURATION:P1D
 RRULE:FREQ=DAILY;INTERVAL=3
 SUMMARY:Every third day
 UID:baff9b6a-a161-4057-bd9c-d76359dc90b1

Ical.Net.Tests/Calendars/Recurrence/DailyInterval2.ics

@@ -2,7 +2,7 @@ BEGIN:VCALENDAR
 VERSION:2.0
 PRODID:-//ddaysoftware.com//NONSGML DDay.iCal 1.0//EN
 BEGIN:VEVENT
-DTEND:20070410T070000
+DURATION:P1D
 DTSTART:20070409T070000
 RRULE:FREQ=DAILY;INTERVAL=2
 SUMMARY:Every 2 days

Ical.Net.Tests/Calendars/Recurrence/HourlyInterval1.ics

@@ -6,7 +6,6 @@ CREATED:20070405T013153Z
 DTEND;TZID=US-Eastern:20070410T070000
 DTSTAMP:20070405T013153Z
 DTSTART;TZID=US-Eastern:20070409T070000
-DURATION:P1D
 RRULE:FREQ=HOURLY;INTERVAL=18
 SUMMARY:Every 18 hours
 UID:baff9b6a-a161-4057-bd9c-d76359dc90b1

Ical.Net.Tests/Calendars/Recurrence/MonthlyInterval1.ics

@@ -6,7 +6,6 @@ CREATED:20070405T013153Z
 DTEND;TZID=US-Eastern:20070410T070000
 DTSTAMP:20070405T013153Z
 DTSTART;TZID=US-Eastern:20070409T070000
-DURATION:P1D
 RRULE:FREQ=MONTHLY;INTERVAL=2;BYDAY=MO,TU;BYMONTHDAY=8,9,10,11,12,13,14
 SUMMARY:Every other month, on Monday and Tuesday on the 2nd week of the month.
 UID:baff9b6a-a161-4057-bd9c-d76359dc90b1

Ical.Net.Tests/Calendars/Recurrence/YearlyInterval1.ics

@@ -6,7 +6,6 @@ CREATED:20050405T013153Z
 DTEND;TZID=US-Eastern:20050410T070000
 DTSTAMP:20050405T013153Z
 DTSTART;TZID=US-Eastern:20050409T070000
-DURATION:P1D
 RRULE:FREQ=YEARLY;INTERVAL=2;BYDAY=MO,TU;BYMONTHDAY=8,9,10,11,12,13,14
 SUMMARY:Every other year, on Monday and Tuesday on the 2nd week of each month.
 UID:baff9b6a-a161-4057-bd9c-d76359dc90b1

Ical.Net.Tests/DeserializationTests.cs

@@ -128,7 +128,8 @@ public void Bug2938007()
             Assert.Multiple(() =>
             {
                 Assert.That(o.Period.StartTime.HasTime, Is.EqualTo(true));
-                Assert.That(o.Period.EndTime.HasTime, Is.EqualTo(true));
+                Assert.That(o.Period.EndTime, Is.Null);
+                Assert.That(o.Period.EffectiveEndTime, Is.Not.Null);
             });
         }
     }

Ical.Net.Tests/GetOccurrenceTests.cs

@@ -43,7 +43,7 @@ public void WrongDurationTest()
         Assert.Multiple(() =>
         {
             Assert.That(firstOccurrence.Period.StartTime, Is.EqualTo(firstStartCopy));
-            Assert.That(firstOccurrence.Period.EndTime, Is.EqualTo(firstEndCopy));
+            Assert.That(firstOccurrence.Period.EffectiveEndTime, Is.EqualTo(firstEndCopy));
         });
 
         var secondOccurrence = occurrences.Last();
@@ -52,7 +52,7 @@ public void WrongDurationTest()
         Assert.Multiple(() =>
         {
             Assert.That(secondOccurrence.Period.StartTime, Is.EqualTo(secondStartCopy));
-            Assert.That(secondOccurrence.Period.EndTime, Is.EqualTo(secondEndCopy));
+            Assert.That(secondOccurrence.Period.EffectiveEndTime, Is.EqualTo(secondEndCopy));
         });
     }
 

Ical.Net.Tests/PeriodTests.cs

@@ -85,19 +85,4 @@ public void Timezones_StartTime_EndTime_MustBeEqual()
             }
         });
     }
-
-    [Test]
-    public void CollidesWithPeriod()
-    {
-        var period1 = new Period(new CalDateTime(2025, 1, 1, 0, 0, 0), Duration.FromHours(1));
-        var period2 = new Period(new CalDateTime(2025, 1, 1, 0, 30, 0), Duration.FromHours(1));
-        var period3 = new Period(new CalDateTime(2025, 1, 1, 1, 30, 0), Duration.FromHours(1));
-
-        Assert.Multiple(() =>
-        {
-            Assert.That(period1.CollidesWith(period2), Is.True);
-            Assert.That(period1.CollidesWith(period3), Is.False);
-            Assert.That(period2.CollidesWith(period3), Is.True);
-        });
-    }
 }

Ical.Net.Tests/RecurrenceTests.cs

@@ -55,7 +55,7 @@ int eventIndex
 
             for (var i = 0; i < expectedPeriods.Length; i++)
             {
-                var period = new Period(expectedPeriods[i].StartTime, expectedPeriods[i].EffectiveEndTime);
+                var period = new Period(expectedPeriods[i].StartTime, expectedPeriods[i].EffectiveDuration!.Value);
 
                 Assert.That(occurrences[i].Period, Is.EqualTo(period), "Event should occur on " + period);
                 if (timeZones != null)
@@ -2539,14 +2539,14 @@ public void Bug3007244()
     // specified via DTEND: exact
     [TestCase("DTSTART;TZID=Europe/Vienna:20241020T010000", "DTEND;TZID=Europe/Vienna:20241021T040000", "20241020T010000/PT27H", "20241027T010000/PT27H", "20241103T010000/PT27H")]
     // First days are applied nominal, then time exact
-    [TestCase("DTSTART;TZID=Europe/Vienna:20241020T010000", "DURATION:P1DT3H",                          "20241020T010000/PT27H", "20241027T010000/PT28H", "20241103T010000/PT27H")]
+    [TestCase("DTSTART;TZID=Europe/Vienna:20241020T010000", "DURATION:P1DT3H",                          "20241020T010000/P1DT3H", "20241027T010000/P1DT3H", "20241103T010000/P1DT3H")]
     // Exact, because duration is time-only
     [TestCase("DTSTART;TZID=Europe/Vienna:20241020T010000", "DURATION:PT27H",                           "20241020T010000/PT27H", "20241027T010000/PT27H", "20241103T010000/PT27H")]
 
     // specified via DTEND: exact
     [TestCase("DTSTART;TZID=Europe/Vienna:20241020T010000", "DTEND;TZID=Europe/Vienna:20241027T040000", "20241020T010000/PT172H", "20241027T010000/PT172H", "20241103T010000/PT172H")]
     // First days are applied nominal, then time exact
-    [TestCase("DTSTART;TZID=Europe/Vienna:20241020T010000", "DURATION:P7DT3H",                          "20241020T010000/PT171H", "20241027T010000/PT172H", "20241103T010000/PT171H")]
+    [TestCase("DTSTART;TZID=Europe/Vienna:20241020T010000", "DURATION:P7DT3H",                          "20241020T010000/P7DT3H", "20241027T010000/P7DT3H", "20241103T010000/P7DT3H")]
     // Exact, because duration is time-only
     [TestCase("DTSTART;TZID=Europe/Vienna:20241020T010000", "DURATION:PT171H",                          "20241020T010000/PT171H", "20241027T010000/PT171H", "20241103T010000/PT171H")]
 
@@ -2575,8 +2575,8 @@ public void Bug3007244()
     //
     // see https://github.com/ical-org/ical.net/issues/681
     [TestCase("DTSTART;TZID=Europe/Vienna:20250316T023000", "DTEND;TZID=Europe/Vienna:20250323T023000", "20250316T023000/PT168H", "20250323T023000/PT168H", "20250330T033000/PT168H")]
-    [TestCase("DTSTART;TZID=Europe/Vienna:20250316T023000", "DURATION:P1W",                             "20250316T023000/PT168H", "20250323T023000/PT168H", "20250330T033000/PT168H")]
-    [TestCase("DTSTART;TZID=Europe/Vienna:20250316T023000", "DURATION:P7D",                             "20250316T023000/PT168H", "20250323T023000/PT168H", "20250330T033000/PT168H")]
+    [TestCase("DTSTART;TZID=Europe/Vienna:20250316T023000", "DURATION:P1W",                             "20250316T023000/P1W",    "20250323T023000/P1W",    "20250330T033000/P1W")]
+    [TestCase("DTSTART;TZID=Europe/Vienna:20250316T023000", "DURATION:P7D",                             "20250316T023000/P7D",    "20250323T023000/P7D",    "20250330T033000/P7D")]
 
     public void DurationOfRecurrencesOverDst(string dtStart, string dtEnd, string? d1, string? d2, string? d3)
     {
@@ -2603,7 +2603,7 @@ public void DurationOfRecurrencesOverDst(string dtStart, string dtEnd, string? d
         {
             var p = expectedPeriods[index];
             var newStart = p.StartTime.ToTimeZone(start!.TzId);
-            expectedPeriods[index] = Period.Create(newStart, end: newStart.Add(p.Duration!.Value));
+            expectedPeriods[index] = Period.Create(newStart, duration: p.EffectiveDuration);
         }
 
         // date only cannot have a time zone
@@ -3097,7 +3097,7 @@ public void Test4()
             RDATE;TZID=America/Chicago:99991231T221000
             END:VEVENT
             END:VCALENDAR
-            """)]
+            """, true)]
 
     // y10k exceeded due to the event duration
     [TestCase("""
@@ -3108,7 +3108,7 @@ public void Test4()
             RRULE:FREQ=DAILY;BYHOUR=22,23;COUNT=2
             END:VEVENT
             END:VCALENDAR
-            """)]
+            """, false)]
 
     // Events are merged in different places than individual RRULES of a single event
     [TestCase("""
@@ -3120,11 +3120,11 @@ public void Test4()
             DTSTART;TZID=America/Chicago:99991231T221000
             END:VEVENT
             END:VCALENDAR
-            """)]
-    public void Recurrence_WithOutOfBoundsUtc_ShouldFailWithCorrectException(string ical)
+            """, true)]
+    public void Recurrence_WithOutOfBoundsUtc_ShouldFailWithCorrectException(string ical, bool shouldThrow)
     {
         var cal = Calendar.Load(ical)!;
-        Assert.That(() => cal.GetOccurrences().ToList(), Throws.InstanceOf<EvaluationOutOfRangeException>());
+        Assert.That(() => cal.GetOccurrences().ToList(), shouldThrow ? Throws.InstanceOf<EvaluationOutOfRangeException>() : Throws.Nothing);
     }
 
     [Test, Category("Recurrence")]
@@ -3327,15 +3327,15 @@ public void EventsWithShareUidsShouldGenerateASingleRecurrenceSet()
         Assert.Multiple(() =>
         {
             Assert.That(orderedOccurrences[3].StartTime, Is.EqualTo(expectedSept1Start));
-            Assert.That(orderedOccurrences[3].EndTime, Is.EqualTo(expectedSept1End));
+            Assert.That(orderedOccurrences[3].EffectiveEndTime, Is.EqualTo(expectedSept1End));
         });
 
         var expectedSept3Start = new CalDateTime(DateTime.Parse("2016-09-03T07:00:00", CultureInfo.InvariantCulture), "Europe/Bucharest");
         var expectedSept3End = new CalDateTime(DateTime.Parse("2016-09-03T12:30:00", CultureInfo.InvariantCulture), "Europe/Bucharest");
         Assert.Multiple(() =>
         {
             Assert.That(orderedOccurrences[5].StartTime, Is.EqualTo(expectedSept3Start));
-            Assert.That(orderedOccurrences[5].EndTime, Is.EqualTo(expectedSept3End));
+            Assert.That(orderedOccurrences[5].EffectiveEndTime, Is.EqualTo(expectedSept3End));
         });
     }
 
@@ -3790,7 +3790,7 @@ Type LoadType(string name) =>
 
         if (testCase.ExceptionStep == RecurrenceTestExceptionStep.Enumeration)
         {
-            Assert.That(() => EnumerateOccurrences(), throwsConstraint);
+            Assert.That(() => EnumerateOccurrences().Last().Period.EffectiveEndTime, throwsConstraint);
             return;
         }
 
@@ -4031,4 +4031,37 @@ public void Disallowed_Recurrence_RangeChecks_Should_Throw()
             Assert.That(() => serializer.CheckRange("a", (int?) 0, 1, 2, false), Throws.TypeOf<ArgumentOutOfRangeException>());
         });
     }
+
+    [Test]
+    public void AmbiguousLocalTime_WithShortDurationOfRecurrence()
+    {
+        // Short recurrence falls into an ambiguous local time
+        // for the end time of the second occurrence because
+        // of DST transition on 2025-10-25 03:00
+        // See also: https://github.com/ical-org/ical.net/issues/737
+        var ics = """
+                  BEGIN:VCALENDAR
+                  BEGIN:VEVENT
+                  DTSTART;TZID=Europe/Vienna:20201024T023000
+                  DURATION:PT45M
+                  RRULE:FREQ=DAILY;UNTIL=20201025T013000Z
+                  END:VEVENT
+                  END:VCALENDAR
+                  """;
+        var cal = Calendar.Load(ics)!;
+        var occ = cal.GetOccurrences().ToList();
+
+        Assert.Multiple(() =>
+        {
+            Assert.That(occ.Count, Is.EqualTo(2));
+
+            Assert.That(occ[0].Period.StartTime, Is.EqualTo(new CalDateTime(2020, 10, 24, 2, 30, 0, "Europe/Vienna")));
+            Assert.That(occ[0].Period.EffectiveEndTime, Is.EqualTo(new CalDateTime(2020, 10, 24, 3, 15, 0, "Europe/Vienna")));
+            Assert.That(occ[0].Period.EffectiveDuration, Is.EqualTo(new Duration(0, 0, 0, 45, 0)));
+
+            Assert.That(occ[1].Period.StartTime, Is.EqualTo(new CalDateTime(2020, 10, 25, 2, 30, 0, "Europe/Vienna")));
+            Assert.That(occ[1].Period.EffectiveEndTime, Is.EqualTo(new CalDateTime(2020, 10, 25, 2, 15, 0, "Europe/Vienna")));
+            Assert.That(occ[1].Period.EffectiveDuration, Is.EqualTo(new Duration(0, 0, 0, 45, 0)));
+        });
+    }
 }

Ical.Net.Tests/RecurrenceTests_From_Issues.cs

@@ -85,7 +85,7 @@ public void ClockGoingForwardTest()
             Assert.That(occurrences.Count(), Is.EqualTo(1));
             Assert.That(occurrence.Source, Is.SameAs(myEvent));
             Assert.That(occurrence.Period.StartTime, Is.EqualTo(myEvent.Start));
-            Assert.That(occurrence.Period.EndTime, Is.EqualTo(myEvent.End));
+            Assert.That(occurrence.Period.EffectiveEndTime, Is.EqualTo(myEvent.End));
         });
     }
 
@@ -119,7 +119,7 @@ public void ClockGoingBackTest()
             Assert.That(occurrences.Count(), Is.EqualTo(1));
             Assert.That(occurrence.Source, Is.SameAs(myEvent));
             Assert.That(occurrence.Period.StartTime, Is.EqualTo(myEvent.Start));
-            Assert.That(occurrence.Period.EndTime, Is.EqualTo(myEvent.End));
+            Assert.That(occurrence.Period.EffectiveEndTime, Is.EqualTo(myEvent.End));
         });
     }
 
@@ -156,8 +156,8 @@ public void ClockGoingForwardAllDayTest()
             Assert.That(occurrence.Source, Is.SameAs(myEvent));
             Assert.That(occurrence.Period.StartTime.HasTime, Is.False);
             Assert.That(occurrence.Period.StartTime, Is.EqualTo(myEvent.Start));
-            Assert.That(occurrence.Period.EndTime?.HasTime, Is.False);
-            Assert.That(occurrence.Period.EndTime, Is.EqualTo(myEvent.End));
+            Assert.That(occurrence.Period.EndTime, Is.Null);
+            Assert.That(occurrence.Period.EffectiveEndTime, Is.EqualTo(myEvent.End));
         });
     }
 
@@ -195,8 +195,8 @@ public void ClockGoingBackAllDayTest()
             Assert.That(occurrence.Source, Is.SameAs(myEvent));
             Assert.That(occurrence.Period.StartTime.HasTime, Is.False);
             Assert.That(occurrence.Period.StartTime, Is.EqualTo(myEvent.Start));
-            Assert.That(occurrence.Period.EndTime?.HasTime, Is.False);
-            Assert.That(occurrence.Period.EndTime, Is.EqualTo(myEvent.End));
+            Assert.That(occurrence.Period.EndTime, Is.Null);
+            Assert.That(occurrence.Period.EffectiveEndTime, Is.EqualTo(myEvent.End));
         });
     }
 
@@ -233,8 +233,8 @@ public void ClockGoingBackAllDayNonLocalTest()
             Assert.That(occurrence.Source, Is.SameAs(myEvent));
             Assert.That(occurrence.Period.StartTime.HasTime, Is.False);
             Assert.That(occurrence.Period.StartTime, Is.EqualTo(myEvent.Start));
-            Assert.That(occurrence.Period.EndTime?.HasTime, Is.False);
-            Assert.That(occurrence.Period.EndTime, Is.EqualTo(myEvent.End));
+            Assert.That(occurrence.Period.EndTime, Is.Null);
+            Assert.That(occurrence.Period.EffectiveEndTime, Is.EqualTo(myEvent.End));
         });
     }
 
@@ -271,8 +271,8 @@ public void ClockGoingForwardAllDayNonLocalTest()
             Assert.That(myEvent.IsAllDay, Is.True);
             Assert.That(occurrence.Period.StartTime.HasTime, Is.False);
             Assert.That(occurrence.Period.StartTime, Is.EqualTo(myEvent.Start));
-            Assert.That(occurrence.Period.EndTime?.HasTime, Is.False);
-            Assert.That(occurrence.Period.EndTime, Is.EqualTo(myEvent.End));
+            Assert.That(occurrence.Period.EndTime, Is.Null);
+            Assert.That(occurrence.Period.EffectiveEndTime, Is.EqualTo(myEvent.End));
         });
     }
 

Ical.Net.Tests/RecurrenceWithExDateTests.cs

@@ -64,7 +64,7 @@ public void ShouldNotOccurOnLocalExceptionDate(bool useExDateWithTime)
         {
             if (useExDateWithTime)
             {
-                Assert.That(occurrences.Single().Period, Is.EqualTo(new Period(start, end)));
+                Assert.That(occurrences.Single().Period, Is.EqualTo(new Period(start, end.Subtract(start))));
                 Assert.That(ics, Does.Contain("EXDATE;TZID=Europe/London:20241019T210000"));
             }
             else

Ical.Net.Tests/RecurrenceWithRDateTests.cs

@@ -395,6 +395,6 @@ public void RDate_DateOnly_WithExactDuration_ShouldThrow()
         };
         calendarEvent.RecurrenceDates.AddRange(recurrenceDates);
 
-        Assert.That(() => { _ = calendarEvent.GetOccurrences().ToList(); }, Throws.InvalidOperationException);
+        Assert.That(() => { _ = calendarEvent.GetOccurrences().ToList(); }, Throws.ArgumentException);
     }
 }

Ical.Net.Tests/SimpleDeserializationTests.cs

@@ -123,16 +123,17 @@ public void Bug2938007()
         var evt = iCal.Events.First();
         Assert.Multiple(() =>
         {
-            Assert.That(evt.Start.HasTime, Is.EqualTo(true));
-            Assert.That(evt.End.HasTime, Is.EqualTo(true));
+            Assert.That(evt.Start.HasTime, Is.True);
+            Assert.That(evt.End.HasTime, Is.True);
         });
 
         foreach (var o in evt.GetOccurrences(new CalDateTime(2010, 1, 17, 0, 0, 0)).TakeWhileBefore(new CalDateTime(2010, 2, 1, 0, 0, 0)))
         {
             Assert.Multiple(() =>
             {
                 Assert.That(o.Period.StartTime.HasTime, Is.EqualTo(true));
-                Assert.That(o.Period.EndTime.HasTime, Is.EqualTo(true));
+                Assert.That(o.Period.EndTime, Is.Null);
+                Assert.That(o.Period.EffectiveEndTime, Is.Not.Null);
             });
         }
     }