Add more XQuery 3.1 keywords to reservedKeywords rule

exist-core/src/main/antlr/org/exist/xquery/parser/XQuery.g

@@ -2304,6 +2304,26 @@ reservedKeywords returns [String name]
 	"next" { name = "next"; }
 	|
 	"when" { name = "when"; }
+	|
+	"ascending" { name = "ascending"; }
+	|
+	"descending" { name = "descending"; }
+	|
+	"greatest" { name = "greatest"; }
+	|
+	"least" { name = "least"; }
+	|
+	"satisfies" { name = "satisfies"; }
+	|
+	"schema-attribute" { name = "schema-attribute"; }
+	|
+	"castable" { name = "castable"; }
+	|
+	"idiv" { name = "idiv"; }
+	|
+	"processing-instruction" { name = "processing-instruction"; }
+	|
+	"allowing" { name = "allowing"; }
 	;
 
 

exist-core/src/test/java/org/exist/xquery/ReservedKeywordsAsNCNamesTest.java

@@ -0,0 +1,115 @@
+/*
+ * eXist-db Open Source Native XML Database
+ * Copyright (C) 2001 The eXist-db Authors
+ *
+ * info@exist-db.org
+ * http://www.exist-db.org
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+ */
+package org.exist.xquery;
+
+import org.exist.test.ExistXmldbEmbeddedServer;
+import org.junit.ClassRule;
+import org.junit.Test;
+import org.xmldb.api.base.ResourceSet;
+import org.xmldb.api.base.XMLDBException;
+import org.xmldb.api.modules.XQueryService;
+
+import static org.junit.Assert.assertEquals;
+
+/**
+ * Verifies that XQuery keywords can be used as variable names (NCNames).
+ *
+ * The reservedKeywords grammar rule lists keywords that are also valid NCNames.
+ * Keywords used in grammar rules but missing from this list cause XPST0003
+ * parse errors when used as variable names.
+ */
+public class ReservedKeywordsAsNCNamesTest {
+
+    @ClassRule
+    public static final ExistXmldbEmbeddedServer existEmbeddedServer =
+            new ExistXmldbEmbeddedServer(false, true, true);
+
+    private ResourceSet execute(final String xquery) throws XMLDBException {
+        final XQueryService xqs = existEmbeddedServer.getRoot().getService(XQueryService.class);
+        return xqs.query(xquery);
+    }
+
+    @Test
+    public void ascendingDescendingAsVariableNames() throws XMLDBException {
+        final ResourceSet result = execute(
+                "let $ascending := 1, $descending := 2 return $ascending + $descending");
+        assertEquals("3", result.getResource(0).getContent().toString());
+    }
+
+    @Test
+    public void greatestLeastAsVariableNames() throws XMLDBException {
+        final ResourceSet result = execute(
+                "let $greatest := 10, $least := 1 return $greatest - $least");
+        assertEquals("9", result.getResource(0).getContent().toString());
+    }
+
+    @Test
+    public void satisfiesAsVariableName() throws XMLDBException {
+        final ResourceSet result = execute(
+                "let $satisfies := 'ok' return $satisfies");
+        assertEquals("ok", result.getResource(0).getContent().toString());
+    }
+
+    @Test
+    public void castableAsVariableName() throws XMLDBException {
+        final ResourceSet result = execute(
+                "let $castable := true() return $castable");
+        assertEquals("true", result.getResource(0).getContent().toString());
+    }
+
+    @Test
+    public void idivAsVariableName() throws XMLDBException {
+        final ResourceSet result = execute(
+                "let $idiv := 42 return $idiv");
+        assertEquals("42", result.getResource(0).getContent().toString());
+    }
+
+    @Test
+    public void processingInstructionAsVariableName() throws XMLDBException {
+        final ResourceSet result = execute(
+                "let $processing-instruction := 'test' return $processing-instruction");
+        assertEquals("test", result.getResource(0).getContent().toString());
+    }
+
+    @Test
+    public void schemaAttributeAsVariableName() throws XMLDBException {
+        final ResourceSet result = execute(
+                "let $schema-attribute := 'sa' return $schema-attribute");
+        assertEquals("sa", result.getResource(0).getContent().toString());
+    }
+
+    @Test
+    public void allowingAsVariableName() throws XMLDBException {
+        final ResourceSet result = execute(
+                "let $allowing := 'yes' return $allowing");
+        assertEquals("yes", result.getResource(0).getContent().toString());
+    }
+
+    @Test
+    public void allKeywordsTogether() throws XMLDBException {
+        final ResourceSet result = execute(
+                "let $ascending := 1, $descending := 2, $greatest := 3, $least := 4,\n" +
+                "    $satisfies := 5, $castable := 6, $idiv := 7\n" +
+                "return $ascending + $descending + $greatest + $least + $satisfies + $castable + $idiv");
+        assertEquals("28", result.getResource(0).getContent().toString());
+    }
+}