fix: allow arbitrary column aliases in LATERAL VIEW

Hive/Spark LATERAL VIEW supports an arbitrary number of column aliases
(e.g. json_tuple yielding many output columns), but the grammar only
absorbed the first two aliases (#2088). Any further aliases were
silently parsed as comma-separated tables in the FROM clause (implicit
cross joins), and because toString() re-emitted them as the join list
the broken AST round-tripped identically and was hard to detect by
inspection.

Generalise the column-alias production to consume any number of
aliases after the first two.

Fixes #2433

Signed-off-by: 付典 <fudianchn@gmail.com>

Author: fudianchn

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

@@ -5053,6 +5053,9 @@ LateralView LateralView() #LateralView:
     [
         LOOKAHEAD(2) ","  { columnAlias.setName(null);  columnAlias.addAliasColumns( columnName); }
         columnName = RelObjectName() { columnAlias.addAliasColumns( columnName); }
+        (
+            LOOKAHEAD(2) "," columnName = RelObjectName() { columnAlias.addAliasColumns( columnName); }
+        )*
     ]
     {
         return new LateralView(

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

@@ -9,13 +9,17 @@
  */
 package net.sf.jsqlparser.statement.select;
 
-import net.sf.jsqlparser.schema.Table;
-import org.junit.jupiter.api.Test;
-
 import static net.sf.jsqlparser.test.TestUtils.assertSqlCanBeParsedAndDeparsed;
 import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertNotNull;
+import static org.junit.jupiter.api.Assertions.assertNull;
 import static org.junit.jupiter.api.Assertions.assertTrue;
 
+import net.sf.jsqlparser.expression.Alias;
+import net.sf.jsqlparser.parser.CCJSqlParserUtil;
+import net.sf.jsqlparser.schema.Table;
+import org.junit.jupiter.api.Test;
+
 public class HiveTest {
 
     @Test
@@ -54,4 +58,30 @@ public void testGroupSimplified() throws Exception {
                 + "GROUP BY GROUPING SETS (())";
         assertSqlCanBeParsedAndDeparsed(sql, true);
     }
+
+    @Test
+    public void testLateralViewManyColumnAliasesIssue2433() throws Exception {
+        // Hive/Spark LATERAL VIEW allows an arbitrary number of column aliases
+        // (e.g. json_tuple yielding many columns). Only the first two were absorbed;
+        // any further aliases leaked into the FROM clause as implicit cross-join
+        // tables, so the failure was silent and even round-tripped identically.
+        String sql = "SELECT a FROM t"
+                + " LATERAL VIEW json_tuple(j, 'a', 'b', 'c', 'd', 'e', 'f', 'g')"
+                + " x AS c1, c2, c3, c4, c5, c6, c7";
+
+        Select select = (Select) CCJSqlParserUtil.parse(sql);
+        PlainSelect plainSelect = (PlainSelect) select.getSelectBody();
+
+        // The extra aliases must not leak as cross-join tables.
+        assertNull(plainSelect.getJoins());
+
+        java.util.List<LateralView> lateralViews = plainSelect.getLateralViews();
+        assertNotNull(lateralViews);
+        assertEquals(1, lateralViews.size());
+
+        Alias columnAlias = lateralViews.get(0).getColumnAlias();
+        assertNotNull(columnAlias);
+        assertNotNull(columnAlias.getAliasColumns());
+        assertEquals(7, columnAlias.getAliasColumns().size());
+    }
 }