[FIX](agg)fix group by constant child expr bug (#13485)

fe/fe-core/src/main/java/org/apache/doris/analysis/GroupByClause.java

@@ -93,20 +93,12 @@ public class GroupByClause implements ParseNode {
     }
 
     public void reset() {
+        groupingExprs = new ArrayList<>();
         analyzed = false;
         exprGenerated = false;
-        if (groupingType != GroupingType.GROUP_BY) {
-            groupingExprs = new ArrayList<>();
-            if (oriGroupingExprs != null) {
-                Expr.resetList(oriGroupingExprs);
-                groupingExprs.addAll(oriGroupingExprs);
-            }
-        } else {
-            if (groupingExprs != null) {
-                for (Expr e : groupingExprs) {
-                    e.reset();
-                }
-            }
+        if (oriGroupingExprs != null) {
+            Expr.resetList(oriGroupingExprs);
+            groupingExprs.addAll(oriGroupingExprs);
         }
         if (groupingSetList != null) {
             for (List<Expr> s : groupingSetList) {

fe/fe-core/src/main/java/org/apache/doris/analysis/SelectStmt.java

@@ -1389,7 +1389,19 @@ public class SelectStmt extends QueryStmt {
             }
             List<Expr> oriGroupingExprs = groupByClause.getOriGroupingExprs();
             if (oriGroupingExprs != null) {
+                // we must make sure the expr is analyzed before rewrite
+                try {
+                    for (Expr expr : oriGroupingExprs) {
+                        expr.analyze(analyzer);
+                    }
+                } catch (AnalysisException ex) {
+                    //ignore any exception
+                }
                 rewriter.rewriteList(oriGroupingExprs, analyzer);
+                // after rewrite, need reset the analyze status for later re-analyze
+                for (Expr expr : oriGroupingExprs) {
+                    expr.reset();
+                }
             }
         }
         if (orderByElements != null) {

regression-test/data/correctness_p0/test_group_by_constant.out

@@ -2,3 +2,6 @@
 -- !sql --
 D
 
+-- !sql --
+D
+

regression-test/suites/correctness_p0/test_group_by_constant.groovy

@@ -57,6 +57,20 @@ suite("test_group_by_constant") {
         end;
     """
 
+    qt_sql """
+        SELECT
+        case
+            when (inc_day = date_sub(curdate(), interval 1 day)) then 'A'
+            when (inc_day = date_sub(curdate(), interval 8 day)) then 'B'
+            when (inc_day = date_sub(curdate(), interval 365 day)) then 'C'
+            else 'D'
+        end val
+        from
+        table_group_by_constant
+        group by
+        val;
+    """
+
     sql """
         DROP TABLE IF EXISTS `table_group_by_constant`;
     """