MDEV-22084 Squared brackets missing from JSON_ARRAYAGG when used in a view.

Item_func_groupconcat::print() should be fixed to work for the derived
classes.

mysql-test/main/func_json.result

@@ -1235,6 +1235,11 @@ JSON_ARRAYAGG(NULL)
 SELECT JSON_ARRAYAGG("null") FROM (SELECT 1 AS t) AS A;
 JSON_ARRAYAGG("null")
 ["null"]
+create view v as (select json_arrayagg(json_object("type", "permPeriod", "id", "asd")) as JSON_DATA);
+select * from v;
+JSON_DATA
+[{"type": "permPeriod", "id": "asd"}]
+drop view v;
 #
 # End of 10.5 tests
 #

mysql-test/main/func_json.test

@@ -755,6 +755,10 @@ select json_objectagg(a, b) over () from (select 1 a, 2 b) t;
 SELECT JSON_ARRAYAGG(NULL) FROM (SELECT 1 AS t) AS A;
 SELECT JSON_ARRAYAGG("null") FROM (SELECT 1 AS t) AS A;
 
+create view v as (select json_arrayagg(json_object("type", "permPeriod", "id", "asd")) as JSON_DATA);
+select * from v; 
+drop view v;
+
 --echo #
 --echo # End of 10.5 tests
 --echo #

sql/item_sum.cc

@@ -4305,7 +4305,7 @@ String* Item_func_group_concat::val_str(String* str)
 
 void Item_func_group_concat::print(String *str, enum_query_type query_type)
 {
-  str->append(STRING_WITH_LEN("group_concat("));
+  str->append(func_name());
   if (distinct)
     str->append(STRING_WITH_LEN("distinct "));
   for (uint i= 0; i < arg_count_field; i++)
@@ -4328,9 +4328,13 @@ void Item_func_group_concat::print(String *str, enum_query_type query_type)
         str->append(STRING_WITH_LEN(" DESC"));
     }
   }
-  str->append(STRING_WITH_LEN(" separator \'"));
-  str->append_for_single_quote(separator->ptr(), separator->length());
-  str->append(STRING_WITH_LEN("\'"));
+
+  if (sum_func() == GROUP_CONCAT_FUNC)
+  {
+    str->append(STRING_WITH_LEN(" separator \'"));
+    str->append_for_single_quote(separator->ptr(), separator->length());
+    str->append(STRING_WITH_LEN("\'"));
+  }
 
   if (limit_clause)
   {