From: Peter Edberg <pedberg@unicode.org>
Date: Wed, 10 Apr 2019 19:06:57 +0000 (-0700)
Subject: ICU-20550 jaEra: use all valid eras for calendar calculations (#614)
X-Git-Tag: release-64-2-rc~2
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=5b3f1c01ed31f50a24c5e57b4b9cd558982e088e;p=icu

ICU-20550 jaEra: use all valid eras for calendar calculations (#614)
---

diff --git a/icu4c/source/i18n/japancal.cpp b/icu4c/source/i18n/japancal.cpp
index b15761c0bfc..1cb43f364a0 100644
--- a/icu4c/source/i18n/japancal.cpp
+++ b/icu4c/source/i18n/japancal.cpp
@@ -250,7 +250,7 @@ int32_t JapaneseCalendar::handleGetLimit(UCalendarDateFields field, ELimitType l
         if (limitType == UCAL_LIMIT_MINIMUM || limitType == UCAL_LIMIT_GREATEST_MINIMUM) {
             return 0;
         }
-        return gCurrentEra;
+        return gJapaneseEraRules->getNumberOfEras() - 1; // max known era, not gCurrentEra
     case UCAL_YEAR:
         {
             switch (limitType) {
@@ -282,7 +282,7 @@ int32_t JapaneseCalendar::getActualMaximum(UCalendarDateFields field, UErrorCode
         if (U_FAILURE(status)) {
             return 0; // error case... any value
         }
-        if (era == gCurrentEra) {
+        if (era == gJapaneseEraRules->getNumberOfEras() - 1) { // max known era, not gCurrentEra
             // TODO: Investigate what value should be used here - revisit after 4.0.
             return handleGetLimit(UCAL_YEAR, UCAL_LIMIT_MAXIMUM);
         } else {
diff --git a/icu4c/source/test/cintltst/ccaltst.c b/icu4c/source/test/cintltst/ccaltst.c
index d5860ae73c1..ce84ddd870f 100644
--- a/icu4c/source/test/cintltst/ccaltst.c
+++ b/icu4c/source/test/cintltst/ccaltst.c
@@ -40,6 +40,7 @@ void TestGetTZTransition(void);
 
 void TestGetWindowsTimeZoneID(void);
 void TestGetTimeZoneIDByWindowsID(void);
+void TestJpnCalAddSetNextEra();
 
 void addCalTest(TestNode** root);
 
@@ -62,6 +63,7 @@ void addCalTest(TestNode** root)
     addTest(root, &TestGetTZTransition, "tsformat/ccaltst/TestGetTZTransition");
     addTest(root, &TestGetWindowsTimeZoneID, "tsformat/ccaltst/TestGetWindowsTimeZoneID");
     addTest(root, &TestGetTimeZoneIDByWindowsID, "tsformat/ccaltst/TestGetTimeZoneIDByWindowsID");
+    addTest(root, &TestJpnCalAddSetNextEra, "tsformat/ccaltst/TestJpnCalAddSetNextEra");
 }
 
 /* "GMT" */
@@ -2455,5 +2457,51 @@ void TestGetTimeZoneIDByWindowsID() {
     }
 }
 
+// The following currently assumes that Reiwa is the last known/valid era.
+// Filed ICU-20551 to generalize this when we have more time...
+void TestJpnCalAddSetNextEra() {
+    UErrorCode status = U_ZERO_ERROR;
+    UCalendar *jCal = ucal_open(NULL, 0, "ja_JP@calendar=japanese", UCAL_DEFAULT, &status);
+    if ( U_FAILURE(status) ) {
+        log_data_err("FAIL: ucal_open for ja_JP@calendar=japanese, status %s\n", u_errorName(status));
+    } else {
+        ucal_clear(jCal); // This sets to 1970, in Showa
+        int32_t sEra = ucal_get(jCal, UCAL_ERA, &status); // Don't assume era number for Showa
+        if ( U_FAILURE(status) ) {
+            log_data_err("FAIL: ucal_get ERA for Showa, status %s\n", u_errorName(status));
+        } else {
+            int32_t iEra, eYear;
+            int32_t startYears[4] = { 1926, 1989, 2019, 0 }; // start years for Showa, Heisei, Reiwa; 0 marks invalid era
+            for (iEra = 1; iEra < 3; iEra++) {
+                status = U_ZERO_ERROR;
+                ucal_clear(jCal);
+                ucal_set(jCal, UCAL_ERA, sEra+iEra);
+                eYear = ucal_get(jCal, UCAL_EXTENDED_YEAR, &status);
+                if ( U_FAILURE(status) ) {
+                    log_err("FAIL: set %d, ucal_get EXTENDED_YEAR, status %s\n", iEra, u_errorName(status));
+                } else if (eYear != startYears[iEra]) {
+                    log_err("ERROR: set %d, expected start year %d but get %d\n", iEra, startYears[iEra], eYear);
+                } else {
+                    ucal_add(jCal, UCAL_ERA, 1, &status);
+                    if ( U_FAILURE(status) ) {
+                        log_err("FAIL: set %d, ucal_add ERA 1, status %s\n", iEra, u_errorName(status));
+                    } else {
+                        eYear = ucal_get(jCal, UCAL_EXTENDED_YEAR, &status);
+                        if ( U_FAILURE(status) ) {
+                            log_err("FAIL: set %d then add ERA 1, ucal_get EXTENDED_YEAR, status %s\n", iEra, u_errorName(status));
+                        } else {
+                            // If this is the last valid era, we expect adding an era to pin to the current era
+                            int32_t nextEraStart = (startYears[iEra+1] == 0)? startYears[iEra]: startYears[iEra+1];
+                            if (eYear != nextEraStart) {
+                                log_err("ERROR: set %d then add ERA 1, expected start year %d but get %d\n", iEra, nextEraStart, eYear);
+                            }
+                        }
+                    }
+                }
+             }
+        }
+        ucal_close(jCal);
+    }
+}
 
 #endif /* #if !UCONFIG_NO_FORMATTING */