refactor: share PostgreSQL routine argument grammar

src/main/jjtree/net/sf/jsqlparser/parser/JSqlParserCC.jjt

@@ -16382,19 +16382,8 @@ PrivilegeTarget.Kind AccessObjectKind(boolean plural):
 }
 
 RoutineReference.Argument AccessRoutineArgument():
-{ RoutineReference.Argument result = new RoutineReference.Argument(); String name; Token mode; ColDataType type; }
-{
-    [
-        LOOKAHEAD({ isAccessKeywordAhead("IN") || isAccessKeywordAhead("OUT") || isAccessKeywordAhead("INOUT") || isAccessKeywordAhead("VARIADIC") })
-        ( <K_IN> { result.setMode(RoutineReference.Argument.Mode.IN); }
-          | mode=<S_IDENTIFIER> { result.setMode(accessEnum(RoutineReference.Argument.Mode.class, mode.image)); } )
-    ]
-    (
-        LOOKAHEAD(ColDataType() ("," | ")")) type=ColDataType()
-        | name=RelObjectName() { result.setName(name); } type=ColDataType()
-    )
-    { result.setDataType(type); return result; }
-}
+{ RoutineReference.Argument argument; }
+{ argument=RoutineArgument(false) { return argument; } }
 
 RoutineReference AccessRoutine():
 { RoutineReference result = new RoutineReference(); String name; RoutineReference.Argument argument; List<RoutineReference.Argument> arguments; }
@@ -17171,18 +17160,30 @@ CreateExtension CreateExtension():
 }
 
 RoutineReference.Argument RoutineSignatureArgument():
+{ RoutineReference.Argument argument; }
+{ argument=RoutineArgument(true) { return argument; } }
+
+/** Common argument AST; only extension aggregate signatures may end a type at ORDER BY. */
+RoutineReference.Argument RoutineArgument(boolean allowOrderBy):
 { RoutineReference.Argument result = new RoutineReference.Argument(); String name; Token mode; ColDataType type; }
 {
     [
         LOOKAHEAD({ isKeywordAhead("IN") || isKeywordAhead("OUT") || isKeywordAhead("INOUT") || isKeywordAhead("VARIADIC") })
         ( <K_IN> { result.setMode(RoutineReference.Argument.Mode.IN); }
-          | mode=<S_IDENTIFIER> { result.setMode(typeDdlEnum(RoutineReference.Argument.Mode.class, mode.image)); } )
+          | mode=<S_IDENTIFIER> { result.setMode(allowOrderBy
+              ? typeDdlEnum(RoutineReference.Argument.Mode.class, mode.image)
+              : accessEnum(RoutineReference.Argument.Mode.class, mode.image)); } )
     ]
     (
         LOOKAHEAD(ColDataType() ("," | ")" | <K_ORDER>)) type=ColDataType()
         | name=RelObjectName() { result.setName(name); } type=ColDataType()
     )
-    { result.setDataType(type); return result; }
+    {
+        requireAccessSyntax(allowOrderBy || getToken(1).kind != K_ORDER,
+                "ORDER BY requires an aggregate signature");
+        result.setDataType(type);
+        return result;
+    }
 }
 
 RoutineReference RoutineReference(boolean aggregate):

src/test/java/net/sf/jsqlparser/statement/create/PostgreSqlRoutineArgumentTest.java

@@ -0,0 +1,72 @@
+/*-
+ * #%L
+ * JSQLParser library
+ * %%
+ * Copyright (C) 2004 - 2026 JSQLParser
+ * %%
+ * Dual licensed under GNU LGPL 2.1 or Apache License 2.0
+ * #L%
+ */
+package net.sf.jsqlparser.statement.create;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+
+import net.sf.jsqlparser.JSQLParserException;
+import net.sf.jsqlparser.parser.CCJSqlParserUtil;
+import net.sf.jsqlparser.statement.Statement;
+import net.sf.jsqlparser.statement.alter.AlterExtension;
+import net.sf.jsqlparser.statement.grant.Grant;
+import net.sf.jsqlparser.statement.RoutineReference;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.ValueSource;
+
+class PostgreSqlRoutineArgumentTest {
+    @ParameterizedTest
+    @ValueSource(strings = {"integer", "text[]", "IN value integer", "OUT result text",
+            "INOUT state app.custom_type", "VARIADIC items text[]",
+            "\"argument name\" double precision"})
+    void privilegeAndExtensionArgumentsHaveEquivalentAst(String argument)
+            throws JSQLParserException {
+        Grant grant = (Grant) CCJSqlParserUtil.parse(
+                "GRANT EXECUTE ON FUNCTION app.f(" + argument + ") TO reader");
+        AlterExtension extension = (AlterExtension) CCJSqlParserUtil.parse(
+                "ALTER EXTENSION example ADD FUNCTION app.f(" + argument + ")");
+        RoutineReference.Argument access =
+                grant.getTarget().getRoutines().get(0).getArguments().get(0);
+        RoutineReference.Argument member = extension.getMember().getRoutine().getArguments().get(0);
+        assertEquals(access.getMode(), member.getMode());
+        assertEquals(access.getName(), member.getName());
+        assertEquals(access.getDataType().toString(), member.getDataType().toString());
+        assertRoundTrip(grant);
+        assertRoundTrip(extension);
+    }
+
+    @Test
+    void aggregateKeepsOrderByArgumentBoundary() throws JSQLParserException {
+        AlterExtension extension = (AlterExtension) CCJSqlParserUtil.parse(
+                "ALTER EXTENSION example ADD AGGREGATE app.percentile(double precision ORDER BY integer)");
+        RoutineReference routine = extension.getMember().getRoutine();
+        assertEquals(1, routine.getArguments().size());
+        assertEquals(1, routine.getOrderByArguments().size());
+        assertEquals("double precision", routine.getArguments().get(0).getDataType().toString());
+        assertRoundTrip(extension);
+    }
+
+    @ParameterizedTest
+    @ValueSource(strings = {
+            "GRANT EXECUTE ON FUNCTION app.f(integer ORDER BY integer) TO reader",
+            "GRANT EXECUTE ON FUNCTION app.f(*) TO reader",
+            "ALTER EXTENSION example ADD FUNCTION app.f(integer ORDER BY integer)",
+            "ALTER EXTENSION example ADD FUNCTION app.f(*)",
+            "GRANT EXECUTE ON FUNCTION app.f(IN) TO reader"
+    })
+    void aggregateSyntaxDoesNotLeakIntoOtherRoutineContexts(String sql) {
+        assertThrows(JSQLParserException.class, () -> CCJSqlParserUtil.parse(sql));
+    }
+
+    private static void assertRoundTrip(Statement statement) throws JSQLParserException {
+        assertEquals(statement.toString(), CCJSqlParserUtil.parse(statement.toString()).toString());
+    }
+}