[bugfix] Only remove the decimal separator in fn:format-number if there is no decimal separator in the picture, or there are no fractional digits, and the decimal separator is the right-most character

Author: adamretter

exist-core/src/main/java/org/exist/util/CodePointString.java

@@ -353,14 +353,14 @@ public CodePointString insert(final int[] indexes, final int codePoint) {
      * @return this
      */
     public CodePointString removeFirst(final int codePoint) {
-        int idx = -1;
-        for (int i = 0; i < codePoints.length; i++) {
-            if (codePoints[i] == codePoint) {
-                idx = i;
-                break;
-            }
-        }
+        final int idx = indexOf(codePoint);
+        return removeChar(idx);
+    }
 
+    /**
+     * Removes the codepoint at the specified index.
+     */
+    public CodePointString removeChar(final int idx) {
         if (idx > -1) {
             final int[] newCodePoints = new int[codePoints.length - 1];
 

exist-core/src/main/java/org/exist/xquery/functions/fn/FnFormatNumbers.java

@@ -752,7 +752,12 @@ private String format(final NumericValue number, final DecimalFormat decimalForm
 
         // Rule 12 - strip decimal separator if unneeded
         if (!subPicture.hasDecimalSeparator() || fractLen == 0) {
-            formatted.removeFirst(decimalFormat.decimalSeparator);
+            // decimal separator must be the rightmost character in the string
+            final int rightMostIndex = formatted.length() - 1;
+            final int rightMost = formatted.codePointAt(rightMostIndex);
+            if (rightMost == decimalFormat.decimalSeparator) {
+                formatted.removeChar(rightMostIndex);
+            }
         }
 
         // Rule 13 - add exponent if exists