From def5a78cbff7199781010d930253a3a4cbb8631c Mon Sep 17 00:00:00 2001
From: Robin6939 <robinraj6939@gmail.com>
Date: Wed, 25 Dec 2024 11:27:11 +0530
Subject: [PATCH] [bugfix] Fix ForClause PositionalVar empty sequence handling.

---
 .../src/main/java/org/exist/xquery/ForExpr.java    |  6 +++++-
 exist-core/src/test/xquery/xquery3/flwor.xql       | 14 ++++++++++++++
 2 files changed, 19 insertions(+), 1 deletion(-)

diff --git a/exist-core/src/main/java/org/exist/xquery/ForExpr.java b/exist-core/src/main/java/org/exist/xquery/ForExpr.java
index ca8b9c1751a..0fcb918fcc9 100644
--- a/exist-core/src/main/java/org/exist/xquery/ForExpr.java
+++ b/exist-core/src/main/java/org/exist/xquery/ForExpr.java
@@ -229,7 +229,11 @@ private void processItem(LocalVariable var, Item contextItem, Sequence in, Seque
         context.proceed(this);
         context.setContextSequencePosition(p, in);
         if (positionalVariable != null) {
-            at.setValue(new IntegerValue(this, p + 1));
+            if (contextItem.getType() == Type.ANY_ATOMIC_TYPE) {
+                at.setValue(new IntegerValue(this, 0));
+            } else {
+                at.setValue(new IntegerValue(this, p + 1));
+            }
         }
         final Sequence contextSequence = contextItem.toSequence();
         // set variable value to current item
diff --git a/exist-core/src/test/xquery/xquery3/flwor.xql b/exist-core/src/test/xquery/xquery3/flwor.xql
index 42dbabd9d26..20654b92d21 100644
--- a/exist-core/src/test/xquery/xquery3/flwor.xql
+++ b/exist-core/src/test/xquery/xquery3/flwor.xql
@@ -156,3 +156,17 @@ function flwor:allowing-empty($n as xs:integer) {
     return concat("[", $x, "]")
 };
 
+declare
+    %test:args(4)
+    %test:assertEquals(":0")
+    %test:args(2)
+    %test:assertEquals("b:1")
+    %test:args(1)
+    %test:assertEquals("a:1")
+    %test:args(5)
+    %test:assertEquals(":0")
+function flwor:allowing-empty-fix($n as xs:integer) {
+    let $sequence := ("a", "b", "c")[$n]
+    for $x allowing empty at $y in $sequence
+    return $x || ":" || $y
+};