Fix timezone issue

#126

src/main/java/biweekly/io/ICalTimeZone.java

@@ -408,20 +408,26 @@ private DateValue getObservanceDateClosestToTheGivenDate(Observance observance,
 			RecurrenceIterator it = createIterator(observance);
 
 			/*
-			 * The "advanceTo()" method skips all dates that are less than the
-			 * given date. I would have thought that we would have to call
-			 * "next()" once because we want it to skip the date that is equal
-			 * to the "last" date. But this causes all the unit tests to fail,
-			 * so I guess not.
+			 * Calling "it.advanceTo()" here causes problems.
+			 * 
+			 * See: https://github.com/mangstadt/biweekly/issues/126
 			 */
-			it.advanceTo(last);
-			//it.next();
+			//it.advanceTo(last);
 
 			DateValue prev = null, cur = null;
 			boolean stopped = false;
 			while (it.hasNext()) {
 				cur = it.next();
-				dateCache.add(cur);
+				int curCompareToLast = cur.compareTo(last);
+				if (curCompareToLast < 0) {
+					continue;
+				}
+				if (curCompareToLast > 0) {
+					dateCache.add(cur);
+				}
+				if (curCompareToLast == 0) {
+					//do nothing; don't add to dateCache
+				}
 
 				if (givenDate.compareTo(cur) < 0) {
 					//stop if we have passed the givenTime

src/test/java/biweekly/issues/Issue115.java

@@ -0,0 +1,57 @@
+package biweekly.issues;
+
+import static biweekly.util.TestUtils.date;
+import static org.junit.Assert.assertEquals;
+
+import java.util.Date;
+
+import org.junit.Test;
+
+import biweekly.Biweekly;
+import biweekly.ICalendar;
+import biweekly.component.VEvent;
+
+/**
+ * @author Michael Angstadt
+ * @see "https://github.com/mangstadt/biweekly/issues/115"
+ */
+public class Issue115 {
+	@Test
+	public void test1() throws Exception {
+		ICalendar ical = Biweekly.parse(getClass().getResourceAsStream("issue115-1.ics")).first();
+
+		/*
+		 * The event comes before the last Sunday in October, so it should
+		 * be in daylight time (offset of +02:00).
+		 */
+		VEvent event = ical.getEvents().get(0);
+
+		Date expected = date(2022, 10, 29, 8, 0, 0, "+0200");
+		Date actual = event.getDateStart().getValue();
+		assertEquals(expected, actual);
+
+		expected = date(2022, 10, 29, 8, 30, 0, "+0200");
+		actual = event.getDateEnd().getValue();
+		assertEquals(expected, actual);
+	}
+
+	@Test
+	public void test2() throws Exception {
+		ICalendar ical = Biweekly.parse(getClass().getResourceAsStream("issue115-2.ics")).first();
+
+		/*
+		 * The event comes after the last Sunday in October, so it should
+		 * be in standard time (offset of +01:00).
+		 */
+		VEvent event = ical.getEvents().get(0);
+
+		Date expected = date(2022, 10, 31, 8, 0, 0, "+0100");
+		System.out.println(expected);
+		Date actual = event.getDateStart().getValue();
+		assertEquals(expected, actual);
+
+		expected = date(2022, 10, 31, 8, 30, 0, "+0100");
+		actual = event.getDateEnd().getValue();
+		assertEquals(expected, actual);
+	}
+}

src/test/java/biweekly/issues/Issue126.java

@@ -0,0 +1,55 @@
+package biweekly.issues;
+
+import static biweekly.util.TestUtils.date;
+import static org.junit.Assert.assertEquals;
+
+import java.util.Date;
+
+import org.junit.Test;
+
+import biweekly.Biweekly;
+import biweekly.ICalendar;
+import biweekly.component.VEvent;
+
+/**
+ * @author Michael Angstadt
+ * @see "https://github.com/mangstadt/biweekly/issues/126"
+ */
+public class Issue126 {
+	@Test
+	public void test() throws Exception {
+		ICalendar ical = Biweekly.parse(getClass().getResourceAsStream("issue126.ics")).first();
+
+		/*
+		 * The first event comes after the last Sunday in October, so it should
+		 * be in standard time (offset of +01:00).
+		 */
+		{
+			VEvent event = ical.getEvents().get(0);
+
+			Date expected = date(2023, 11, 22, 9, 30, 0, "+0100");
+			Date actual = event.getDateStart().getValue();
+			assertEquals(expected, actual);
+
+			expected = date(2023, 11, 22, 12, 0, 0, "+0100");
+			actual = event.getDateEnd().getValue();
+			assertEquals(expected, actual);
+		}
+
+		/*
+		 * The second event comes after the last Sunday in March, so it should
+		 * be in daylight time (offset of +02:00).
+		 */
+		{
+			VEvent event = ical.getEvents().get(1);
+
+			Date expected = date(2023, 4, 22, 9, 30, 0, "+0200");
+			Date actual = event.getDateStart().getValue();
+			assertEquals(expected, actual);
+
+			expected = date(2023, 4, 22, 12, 0, 0, "+0200");
+			actual = event.getDateEnd().getValue();
+			assertEquals(expected, actual);
+		}
+	}
+}