[hotfix] Fix use of Function References within Predicates

Closes #4412

Author: adamretter

exist-core/src/main/java/org/exist/xquery/DynamicFunctionCall.java

@@ -45,6 +45,17 @@ public DynamicFunctionCall(final XQueryContext context, final Expression fun, fi
         this.isPartial = partial;
     }
 
+    @Override
+    public int getDependencies() {
+        int dependencies = functionExpr.getDependencies();
+        if (arguments != null) {
+            for (final Expression argument : arguments) {
+                dependencies |= argument.getDependencies();
+            }
+        }
+        return dependencies;
+    }
+
     @Override
     public void analyze(AnalyzeContextInfo contextInfo) throws XPathException {
         cachedContextInfo = new AnalyzeContextInfo(contextInfo);
@@ -94,7 +105,7 @@ public Sequence eval(Sequence contextSequence, Item contextItem)
 	        ref.analyze(new AnalyzeContextInfo(cachedContextInfo));
 	        // Evaluate the function
             try {
-                return ref.eval(contextSequence);
+                return ref.eval(contextSequence, contextItem);
             } catch (XPathException e) {
                 if (e.getLine() <= 0) {
                     e.setLocation(getLine(), getColumn(), getSource());

exist-core/src/main/java/org/exist/xquery/functions/array/ArrayType.java

@@ -214,6 +214,11 @@ public Sequence eval(Sequence contextSequence) throws XPathException {
         return accessorFunc.eval(contextSequence);
     }
 
+    @Override
+    public Sequence eval(final Sequence contextSequence, final Item contextItem) throws XPathException {
+        return accessorFunc.eval(contextSequence, contextItem);
+    }
+
     @Override
     public Sequence evalFunction(final Sequence contextSequence, final Item contextItem, final Sequence[] seq) throws XPathException {
         final AccessorFunc af =  (AccessorFunc) accessorFunc.getFunction();

exist-core/src/main/java/org/exist/xquery/functions/map/AbstractMapType.java

@@ -111,6 +111,11 @@ public Sequence eval(Sequence contextSequence) throws XPathException {
         return getAccessorFunc().eval(contextSequence);
     }
 
+    @Override
+    public Sequence eval(final Sequence contextSequence, final Item contextItem) throws XPathException {
+        return getAccessorFunc().eval(contextSequence, contextItem);
+    }
+
     @Override
     public Sequence evalFunction(final Sequence contextSequence, final Item contextItem, final Sequence[] seq) throws XPathException {
         final AccessorFunc accessorFunc =  (AccessorFunc) getAccessorFunc().getFunction();

exist-core/src/main/java/org/exist/xquery/value/FunctionReference.java

@@ -86,6 +86,18 @@ public Sequence eval(Sequence contextSequence) throws XPathException {
         return functionCall.eval(contextSequence);
     }
 
+    /**
+     * Calls {@link FunctionCall#eval(Sequence, Item)}.
+     *
+     * @param contextSequence the input sequence
+     * @param contextItem optional: the current context item
+     * @return evaluation result of the function call
+     * @throws XPathException in case of dynamic error
+     */
+    public Sequence eval(final Sequence contextSequence, final Item contextItem) throws XPathException {
+        return functionCall.eval(contextSequence, contextItem);
+    }
+
     /**
      * Calls {@link FunctionCall#evalFunction(Sequence, Item, Sequence[])}.
      *

exist-core/src/test/xquery/xquery3/fnRefs.xql

@@ -52,3 +52,29 @@ function fnRefs:concat-arity2() {
         fn:concat#2
     )
 };
+
+declare
+    %test:assertEquals("b")
+function fnRefs:call-from-predicate() {
+    let $predicate := function($x as xs:string, $y as xs:string) as xs:boolean { $x eq $y }
+    return
+        ("a", "b", "c")[$predicate("b", .)]
+};
+
+declare function fnRefs:pred($x as xs:string, $y as xs:string) as xs:boolean {
+    $x eq $y
+};
+
+declare
+    %test:assertEquals("b")
+function fnRefs:call-from-predicate-via-variable() {
+    let $predicate := fnRefs:pred#2
+    return
+        ("a", "b", "c")[$predicate("b", .)]
+};
+
+declare
+    %test:assertEquals("b")
+function fnRefs:call-from-predicate-inline() {
+    ("a", "b", "c")[function($x as xs:string, $y as xs:string) as xs:boolean { $x eq $y }("b", .)]
+};