From 63f29c621c3c0f0300ae3876e02794acaeecf831 Mon Sep 17 00:00:00 2001
From: Frank Tang <ftang@chromium.org>
Date: Fri, 30 Aug 2024 19:47:22 -0700
Subject: [PATCH] ICU-22854 Add consistency test against Region API

---
 icu4c/source/test/intltest/regiontst.cpp      | 21 ++++++++++++++++-
 .../com/ibm/icu/dev/test/util/RegionTest.java | 23 ++++++++++++++++++-
 2 files changed, 42 insertions(+), 2 deletions(-)

diff --git a/icu4c/source/test/intltest/regiontst.cpp b/icu4c/source/test/intltest/regiontst.cpp
index d72903b0051..cdbeac793a7 100644
--- a/icu4c/source/test/intltest/regiontst.cpp
+++ b/icu4c/source/test/intltest/regiontst.cpp
@@ -837,7 +837,26 @@ void RegionTest::TestGetRegionForSupplementalDataMatch(void) {
             printf("0x%08x, ", data[i]);
         }
         printf("\n};\n");
-        errln("ulocimp_getRegionForSupplementalData() differs from supplementalData");
+        errln("ulocimp_getRegionForSupplementalData() inconsistent with supplementalData");
+    }
+
+    // Ensure consistency with Region API.
+    MutableRegionValidateMap prefab2;
+    char code[3] = "AA";
+    for (code[0] ='A' ; code[0] <= 'Z'; code[0]++) {
+        for (code[1] ='A' ; code[1] <= 'Z'; code[1]++) {
+            status = U_ZERO_ERROR;
+            const Region *r = Region::getInstance(code, status);
+            // The Region code successfully created by Region::getInstance with
+            // type URGN_TERRITORY. Notice the r->getRegionCode() may not be the
+            // same as the same as the one calling getInstance.
+            if (U_SUCCESS(status) && (r != nullptr) && r->getType() == URGN_TERRITORY ) {
+                 prefab2.add(r->getRegionCode());
+            }
+        }
+    }
+    if (!prefab2.equals(builtin)) {
+        errln("ulocimp_getRegionForSupplementalData() inconsistent with Region::getInstance");
     }
 }
 
diff --git a/icu4j/main/core/src/test/java/com/ibm/icu/dev/test/util/RegionTest.java b/icu4j/main/core/src/test/java/com/ibm/icu/dev/test/util/RegionTest.java
index 709497f2626..579b9d9fc58 100644
--- a/icu4j/main/core/src/test/java/com/ibm/icu/dev/test/util/RegionTest.java
+++ b/icu4j/main/core/src/test/java/com/ibm/icu/dev/test/util/RegionTest.java
@@ -670,7 +670,28 @@ public class RegionTest extends CoreTestFmwk {
                 System.out.printf("0x%08x, ", data[i]);
             }
             System.out.println("\n};");
-            errln("Error !!!!");
+            errln("ULocale.RegionValidateMap.BUILTIN inconsistent with supplementalData)");
+        }
+        MutableRegionValidateMap prefab2 = new MutableRegionValidateMap();
+        char[] code = new char[2];
+        for (code[0] = 'A'; code[0] <= 'Z'; code[0]++) {
+            for (code[1] = 'A'; code[1] <= 'Z'; code[1]++) {
+                String str = new String(code);
+                try {
+                    Region r = Region.getInstance(str);
+                    // The Region code successfully created by Region.getInstance with
+                    // type URGN_TERRITORY. Notice the r.toString() may not be the
+                    // same as the same as the one passing into getInstance.
+                    if (r.getType() == Region.RegionType.TERRITORY) {
+                        prefab2.add(r.toString());
+                    }
+                } catch (Exception e) {
+                    // noop
+                }
+            }
+        }
+        if (!ULocale.RegionValidateMap.BUILTIN.equals(prefab2)) {
+            errln("ULocale.RegionValidateMap.BUILTIN inconsistent with Region.getInstance()");
         }
     }
 }