CLDR-15693 Improve CurrencyDateInfo ordering, add test for XML file ordering, fix data

common/supplemental/supplementalData.xml

@@ -1145,12 +1145,12 @@ The printed version of ISO-4217:2001
             <currency iso4217="DEM" from="1999-09-01" to="2002-03-09"/>
             <currency iso4217="YUM" from="1994-01-24" to="1999-09-30"/><!-- Yugoslavian history. YU was renamed to CS. -->
         </region>
-        <region iso3166="YE">
-            <currency iso4217="YER" from="1990-05-22"/><!-- You might be able to say 1964-05-08 is the starting date -->
-        </region>
         <region iso3166="YD">
             <currency iso4217="YDD" from="1965-04-01" to="1996-01-01"/>
         </region>
+        <region iso3166="YE">
+            <currency iso4217="YER" from="1990-05-22"/><!-- You might be able to say 1964-05-08 is the starting date -->
+        </region>
         <region iso3166="YT">
             <currency iso4217="EUR" from="1999-01-01"/>
             <currency iso4217="FRF" from="1976-02-23" to="2002-02-17"/>

docs/ldml/tr35-numbers.md

@@ -1000,6 +1000,8 @@ That is, each `currency` element will list an interval in which it was valid. Th
 <currency iso4217="YUN" from="1994-01-01" to="1994-07-22"/>
 ```
 
+All `currency` elements with `tender="false"` should be at the end of the list for a given `region`. 
+
 The `from` element is limited by the fact that ISO 4217 does not go very far back in time, so there may be no ISO code for the previous currency.
 
 Currencies change relatively frequently. There are different types of changes:

docs/ldml/tr35.md

@@ -4347,6 +4347,8 @@ Other contributors to CLDR are listed on the [CLDR Project Page](https://www.uni
 
 ### Number symbols and formats without numberSystem
 - Noted that [Number Symbols](tr35-numbers.md#Number_Symbols) and [Number Formats](tr35-numbers.md#Number_Formats) without a specific `numberSystem` attribute should not be used and will be deprecated in CLDR v48.
+### Clarified `currencyData` element ordering
+- In [Supplemental Currency Data](tr35-numbers.md#Supplemental_Currency_Data), noted that in the list of `currency` elements for a given `currencyData/region`, those with `tender="false"` should be at the end of the list.
 
 **Changes in LDML Version 46.1 (Differences from Version 46)**
 

tools/cldr-code/src/main/java/org/unicode/cldr/util/SupplementalDataInfo.java

@@ -703,8 +703,25 @@ public boolean isLegalTender() {
 
         @Override
         public int compareTo(CurrencyDateInfo o) {
+            // Sort first by isLegalTender
+            if (isLegalTender && !o.isLegalTender) {
+                return -1;
+            }
+            if (!isLegalTender && o.isLegalTender) {
+                return 1;
+            }
+            // Note that sorting using criteria other than the above loses info, because per
+            // https://www.unicode.org/reports/tr35/tr35-numbers.html#Supplemental_Currency_Data,
+            // "The [xml file] *ordering* of the elements in the list tells us which was the
+            // primary currency during any period in time." However we do keep the further
+            // comparison steps below to preserve a unique ordering of CurrencyDateInfo items; we
+            // just make the ordering closer to the file order by sorting the dateRange newest
+            // first (CLDR-15693).
+            //
+            // Then sort by date range
             int result = dateRange.compareTo(o.dateRange);
-            if (result != 0) return result;
+            if (result != 0) return -result; // want *newest* "to" first, then newest "from"
+            // then by currency
             return currency.compareTo(o.currency);
         }
 

tools/cldr-code/src/test/java/org/unicode/cldr/unittest/TestSupplementalInfo.java

@@ -56,6 +56,7 @@
 import org.unicode.cldr.util.CLDRFile;
 import org.unicode.cldr.util.CLDRFile.WinningChoice;
 import org.unicode.cldr.util.CLDRLocale;
+import org.unicode.cldr.util.CLDRPaths;
 import org.unicode.cldr.util.CLDRURLS;
 import org.unicode.cldr.util.CldrUtility;
 import org.unicode.cldr.util.DateConstants;
@@ -98,6 +99,8 @@
 import org.unicode.cldr.util.SupplementalDataInfo.SampleList;
 import org.unicode.cldr.util.Validity;
 import org.unicode.cldr.util.Validity.Status;
+import org.unicode.cldr.util.XMLFileReader;
+import org.unicode.cldr.util.XPathParts;
 
 public class TestSupplementalInfo extends TestFmwkPlus {
     static CLDRConfig testInfo = CLDRConfig.getInstance();
@@ -1752,6 +1755,91 @@ public void TestCurrencyDecimalPlaces() {
         }
     }
 
+    private List<Row.R3<String, CurrencyDateInfo, String>> currencyDataRegionEntries =
+            new ArrayList<Row.R3<String, CurrencyDateInfo, String>>();
+
+    public void TestCurrencyDataOrder() {
+        // We need to check the order of currencyData/region entries in the xml file, so use
+        // XMLFileReader to get a list of the necessary item data in file order instead of
+        // accessing through SupplementalDataInfo
+        CurrencyDataHandler currencyDataHandler = new CurrencyDataHandler();
+        XMLFileReader xfr = new XMLFileReader().setHandler(currencyDataHandler);
+        String pathToSupplemental =
+                CLDRPaths.DEFAULT_SUPPLEMENTAL_DIRECTORY + "supplementalData.xml";
+        xfr.read(pathToSupplemental, -1, true);
+        currencyDataHandler.cleanup();
+
+        // Now check the list order
+        R3<String, CurrencyDateInfo, String> lastEntry = Row.of("", null, "");
+        for (R3<String, CurrencyDateInfo, String> entry : currencyDataRegionEntries) {
+            String iso3166 = entry.get0();
+            String lastIso3166 = lastEntry.get0();
+            int compareRegions = iso3166.compareTo(lastIso3166);
+            if (compareRegions < 0) {
+                String path = entry.get2();
+                errln(
+                        " currencyData/region "
+                                + iso3166
+                                + " not after "
+                                + lastIso3166
+                                + "; path: "
+                                + path);
+            } else if (compareRegions == 0) {
+                // Check entries within a given region
+                CurrencyDateInfo currencyDateInfo = entry.get1();
+                CurrencyDateInfo lastCurrencyDateInfo = lastEntry.get1();
+                if (currencyDateInfo.isLegalTender() && !lastCurrencyDateInfo.isLegalTender()) {
+                    String path = entry.get2();
+                    errln(
+                            " For currencyData/region "
+                                    + iso3166
+                                    + ", entries with tender=false should be last; path: "
+                                    + path);
+                }
+                // We do not enforce any other ordering of currency entries (i.e. by date range
+                // and/or currency code) since that ordering carries meaning; per
+                // https://www.unicode.org/reports/tr35/tr35-numbers.html#Supplemental_Currency_Data,
+                // "The [xml file] *ordering* of the elements in the list tells us which was the
+                // primary currency during any period in time."
+            } // else we are starting a new region in order
+            lastEntry = entry;
+        }
+    }
+
+    class CurrencyDataHandler extends XMLFileReader.SimpleHandler {
+        public void cleanup() {} // Finish processing anything left in the file
+
+        @Override
+        public void handlePathValue(String path, String value) {
+            try {
+                XPathParts parts = XPathParts.getFrozenInstance(path);
+                if (parts.size() < 4) {
+                    return;
+                }
+                String currencyData = parts.getElement(1);
+                String region = parts.getElement(2);
+                String currency = parts.getElement(3);
+                if (!currencyData.equals("currencyData")
+                        || !region.equals("region")
+                        || !currency.equals("currency")) {
+                    return;
+                }
+                String iso3166 = parts.getAttributeValue(2, "iso3166"); // required
+                String iso4217 = parts.getAttributeValue(3, "iso4217"); // required
+                String fromDate = parts.getAttributeValue(3, "from"); // optional
+                String toDate = parts.getAttributeValue(3, "to"); // optional
+                String tender = parts.getAttributeValue(3, "tender"); // optional
+                CurrencyDateInfo currencyDateInfo =
+                        new CurrencyDateInfo(iso4217, fromDate, toDate, tender);
+                currencyDataRegionEntries.add(Row.of(iso3166, currencyDateInfo, path));
+            } catch (Exception e) {
+                throw (IllegalArgumentException)
+                        new IllegalArgumentException("path: " + path + ",\tvalue: " + value)
+                                .initCause(e);
+            }
+        }
+    }
+
     /** Verify that we have a default script for every CLDR base language */
     public void TestDefaultScripts() {
         SupplementalDataInfo supp = SUPPLEMENTAL;