!2058 修复group by负数的core问题

Merge pull request !2058 from pengjiong/array

src/common/backend/parser/analyze.cpp

@@ -4681,7 +4681,7 @@ static void transformGroupConstToColumn(ParseState* pstate, Node* groupClause, L
                 }
 
                 long target_pos = intVal(val);
-                if (target_pos <= list_length(targetList)) {
+                if (target_pos > 0 && target_pos <= list_length(targetList)) {
                     TargetEntry* tle = (TargetEntry*)list_nth(targetList, target_pos - 1);
                     lfirst(lc) = copyObject(tle->expr);
 

src/test/regress/expected/aggregates_part2.out

@@ -457,6 +457,11 @@ select count(*) from (select distinct(c*d) from t_agg1);
    343
 (1 row)
 
+-- group by with negative value
+SELECT ( 'x' , 'x' ) x GROUP BY -128 , ( );
+ERROR:  GROUP BY position -128 is not in select list
+LINE 1: SELECT ( 'x' , 'x' ) x GROUP BY -128 , ( );
+                                        ^
 reset current_schema;
 drop schema if exists distribute_aggregates_part2 cascade;
 NOTICE:  drop cascades to 3 other objects

src/test/regress/sql/aggregates_part2.sql

@@ -76,5 +76,8 @@ select count(*) from (select distinct(c) from t_agg1);
 explain (costs off) select count(*) from (select distinct(c*d) from t_agg1);
 select count(*) from (select distinct(c*d) from t_agg1);
 
+-- group by with negative value
+SELECT ( 'x' , 'x' ) x GROUP BY -128 , ( );
+
 reset current_schema;
 drop schema if exists distribute_aggregates_part2 cascade;