Parse a parenthesed LATERAL FROM item

isParenthesedFromItemAhead() declines ParenthesedFromItem when the token
after "(" is LATERAL, on the basis that LateralSubSelect handles it.
LateralSubSelect begins at <K_LATERAL>, so it can never match input that
begins at "(", and no later alternative accepts it either. Every
parenthesed LATERAL item therefore fails at the opening parenthesis with
"Encountered: <OPENING_BRACKET>".

Remove the guard so ParenthesedFromItem is tried, as it was before
2d2ee4b replaced the syntactic LOOKAHEAD(ParenthesedFromItem()) with
this two-token predicate.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

Author: edeadington

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

@@ -1202,7 +1202,6 @@ public class CCJSqlParser extends AbstractJSqlParser<CCJSqlParser> {
             if (k2 == K_TABLE && isTableQueryAhead(2)) return false;
             // ( ( SELECT ) UNION ( SELECT ) ) → isNestedSetOperationAhead handles it
             // Other (( patterns: ( (SELECT...) JOIN ... ) or ( (table) ) → ParenthesedFromItem
-            if (k2 == K_LATERAL) return false; // handled by LateralSubSelect
             if (k2 == CLOSING_BRACKET) return false; // empty "()" is not valid
             // EXASOL: ( IMPORT ... ) is a SubImport; handled at the outer FromItem level
             // by LOOKAHEAD(2, Dialect.EXASOL...) SubImport() - must NOT go into ParenthesedFromItem

src/test/java/net/sf/jsqlparser/statement/select/SelectTest.java

@@ -2728,6 +2728,13 @@ public void testLateral1() throws JSQLParserException {
         assertSqlCanBeParsedAndDeparsed(stmt);
     }
 
+    @Test
+    public void testParenthesedLateral() throws JSQLParserException {
+        String stmt =
+                "SELECT O.ORDERID, O.CUSTNAME, OL.LINETOTAL FROM ORDERS AS O, (LATERAL(SELECT SUM(NETAMT) AS LINETOTAL FROM ORDERLINES AS LINES WHERE LINES.ORDERID = O.ORDERID)) AS OL";
+        assertSqlCanBeParsedAndDeparsed(stmt);
+    }
+
     @Test
     public void testLateralComplex1() throws IOException, JSQLParserException {
         String stmt = IOUtils.toString(

src/test/java/net/sf/jsqlparser/statement/select/TableFunctionTest.java

@@ -33,6 +33,19 @@ void testLateralFlat() throws JSQLParserException {
         TestUtils.assertSqlCanBeParsedAndDeparsed(sqlStr, true);
     }
 
+    /**
+     * A LATERAL item may be wrapped in parentheses, in which case it is a parenthesed FROM item
+     * whose content happens to be lateral, not a bare LateralSubSelect.
+     */
+    @Test
+    void testParenthesedLateralFlat() throws JSQLParserException {
+        String sqlStr = "SELECT DIM, count(value) AS COUNT_\n"
+                + "FROM t a,\n"
+                + "(LATERAL FLATTEN(input => a.user_items)) b\n"
+                + "group by 1";
+        TestUtils.assertSqlCanBeParsedAndDeparsed(sqlStr, true);
+    }
+
     /**
      * The SQL keyword "OUTER" is a valid parameter name for Snowflake's FLATTEN table function.
      */