From 44b2617d44911378742948d44e42bab92e02fa34 Mon Sep 17 00:00:00 2001
From: Yoshito Umaoka <y.umaoka@gmail.com>
Date: Wed, 21 Feb 2018 21:09:33 +0000
Subject: [PATCH] ICU-13548 Fixed a calendar calculation problem with setting
 week-of-year and year.

X-SVN-Rev: 40966
---
 icu4c/source/i18n/calendar.cpp                 |  8 ++++----
 icu4c/source/test/intltest/calregts.cpp        | 18 ++++++++++++++++++
 icu4c/source/test/intltest/calregts.h          |  1 +
 .../core/src/com/ibm/icu/util/Calendar.java    |  4 ++--
 .../test/calendar/CalendarRegressionTest.java  | 14 ++++++++++++++
 5 files changed, 39 insertions(+), 6 deletions(-)

diff --git a/icu4c/source/i18n/calendar.cpp b/icu4c/source/i18n/calendar.cpp
index 092dc4c1d9e..526a5a70b4a 100644
--- a/icu4c/source/i18n/calendar.cpp
+++ b/icu4c/source/i18n/calendar.cpp
@@ -3223,14 +3223,14 @@ int32_t Calendar::handleComputeJulianDay(UCalendarDateFields bestField)  {
         bestField == UCAL_DAY_OF_WEEK_IN_MONTH);
     int32_t year;
 
-    if (bestField == UCAL_WEEK_OF_YEAR) {
-        year = internalGet(UCAL_YEAR_WOY, handleGetExtendedYear());
-        internalSet(UCAL_EXTENDED_YEAR, year);
+    if (bestField == UCAL_WEEK_OF_YEAR && newerField(UCAL_YEAR_WOY, UCAL_YEAR) == UCAL_YEAR_WOY) {
+        year = internalGet(UCAL_YEAR_WOY);
     } else {
         year = handleGetExtendedYear();
-        internalSet(UCAL_EXTENDED_YEAR, year);
     }
 
+    internalSet(UCAL_EXTENDED_YEAR, year);
+
 #if defined (U_DEBUG_CAL)
     fprintf(stderr, "%s:%d: bestField= %s - y=%d\n", __FILE__, __LINE__, fldName(bestField), year);
 #endif
diff --git a/icu4c/source/test/intltest/calregts.cpp b/icu4c/source/test/intltest/calregts.cpp
index 24951e5b8aa..da522637c6f 100644
--- a/icu4c/source/test/intltest/calregts.cpp
+++ b/icu4c/source/test/intltest/calregts.cpp
@@ -17,6 +17,7 @@
 #include "unicode/simpletz.h"
 #include "unicode/smpdtfmt.h"
 #include "unicode/strenum.h"
+#include "unicode/localpointer.h"
 #include "cmemory.h"
 #include "caltest.h"
 #include "unicode/localpointer.h"
@@ -94,6 +95,7 @@ CalendarRegressionTest::runIndexedTest( int32_t index, UBool exec, const char* &
         CASE(51,TestT11632);
         CASE(52,TestPersianCalOverflow);
         CASE(53,TestIslamicCalOverflow);
+        CASE(54,TestWeekOfYear13548);
     default: name = ""; break;
     }
 }
@@ -3051,4 +3053,20 @@ void CalendarRegressionTest::TestIslamicCalOverflow(void) {
     }
 }
 
+void CalendarRegressionTest::TestWeekOfYear13548(void) {
+    int32_t year = 2000;
+    UErrorCode status = U_ZERO_ERROR;
+    LocalPointer<Calendar> cal(Calendar::createInstance(status));
+    failure(status, "Calendar::createInstance(status)");
+
+    cal->set(UCAL_YEAR, year);
+    cal->set(UCAL_WEEK_OF_YEAR, 4);
+
+    int32_t resultYear = cal->get(UCAL_YEAR, status);
+    failure(status, "get(UCAL_YEAR, status)");
+    if (year != resultYear) {
+        errln((UnicodeString)"Fail: Expected year=" + year + ", actual=" + resultYear);
+    }
+}
+
 #endif /* #if !UCONFIG_NO_FORMATTING */
diff --git a/icu4c/source/test/intltest/calregts.h b/icu4c/source/test/intltest/calregts.h
index 7d36fab0b45..b4166a0c61d 100644
--- a/icu4c/source/test/intltest/calregts.h
+++ b/icu4c/source/test/intltest/calregts.h
@@ -80,6 +80,7 @@ public:
     void TestT11632(void);
     void TestPersianCalOverflow(void);
     void TestIslamicCalOverflow(void);
+    void TestWeekOfYear13548(void);
 
     void printdate(GregorianCalendar *cal, const char *string);
     void dowTest(UBool lenient) ;
diff --git a/icu4j/main/classes/core/src/com/ibm/icu/util/Calendar.java b/icu4j/main/classes/core/src/com/ibm/icu/util/Calendar.java
index 6529867e708..81d35403ac5 100644
--- a/icu4j/main/classes/core/src/com/ibm/icu/util/Calendar.java
+++ b/icu4j/main/classes/core/src/com/ibm/icu/util/Calendar.java
@@ -5959,12 +5959,12 @@ public abstract class Calendar implements Serializable, Cloneable, Comparable<Ca
 
         int year;
 
-        if (bestField == WEEK_OF_YEAR) {
+        if (bestField == WEEK_OF_YEAR && newerField(YEAR_WOY, YEAR) == YEAR_WOY) {
             // Nota Bene!  It is critical that YEAR_WOY be used as the year here, if it is
             // set.  Otherwise, when WOY is the best field, the year may be wrong at the
             // extreme limits of the year.  If YEAR_WOY is not set then it will fall back.
             // TODO: Should resolveField(YEAR_PRECEDENCE) be brought to bear?
-            year = internalGet(YEAR_WOY, handleGetExtendedYear());
+            year = internalGet(YEAR_WOY);
         } else {
             year = handleGetExtendedYear();
         }
diff --git a/icu4j/main/tests/core/src/com/ibm/icu/dev/test/calendar/CalendarRegressionTest.java b/icu4j/main/tests/core/src/com/ibm/icu/dev/test/calendar/CalendarRegressionTest.java
index 4371b672039..8f73d162178 100644
--- a/icu4j/main/tests/core/src/com/ibm/icu/dev/test/calendar/CalendarRegressionTest.java
+++ b/icu4j/main/tests/core/src/com/ibm/icu/dev/test/calendar/CalendarRegressionTest.java
@@ -2541,5 +2541,19 @@ public class CalendarRegressionTest extends com.ibm.icu.dev.test.TestFmwk {
             }
         }
     }
+
+    @Test
+    public void TestWeekOfYear13548() {
+        int year = 2000;
+
+        Calendar cal = Calendar.getInstance();
+        cal.set(Calendar.YEAR, year);
+        cal.set(Calendar.WEEK_OF_YEAR, 4);
+
+        int resultYear = cal.get(Calendar.YEAR);
+        if (year != resultYear) {
+            errln("Fail: Expected year=" + year + ", actual=" + resultYear);
+        }
+    }
 }
 //eof
-- 
2.40.0