From 36779e624d81fc1cad83b3de7401f0631fbb9a5a Mon Sep 17 00:00:00 2001
From: Varun Gupta <varunraiko1803@gmail.com>
Date: Fri, 18 May 2018 17:42:12 +0530
Subject: [PATCH] MDEV-14623: Output of show function code does not show FETCH
 GROUP NEXT ROW for custom aggregates

The print() function was missing from the FETCH GROUP NEXT ROW instrunction class, so there was no
output for this particular instruction when we use the query SHOW FUNCTION CODE function_name
---
 mysql-test/main/sp-code.result | 21 +++++++++++++++++++++
 mysql-test/main/sp-code.test   | 19 +++++++++++++++++++
 sql/sp_head.cc                 | 11 ++++++++++-
 sql/sp_head.h                  |  2 +-
 4 files changed, 51 insertions(+), 2 deletions(-)

diff --git a/mysql-test/main/sp-code.result b/mysql-test/main/sp-code.result
index 3a4dc9db6f8..001b03a0e3b 100644
--- a/mysql-test/main/sp-code.result
+++ b/mysql-test/main/sp-code.result
@@ -1301,3 +1301,24 @@ Pos	Instruction
 28	jump 4
 29	cpop 1
 DROP PROCEDURE p1;
+#
+# MDEV-14623: Output of show function code does not show FETCH GROUP NEXT ROW
+# for custom aggregates
+#
+create aggregate function f1(x INT) returns int
+begin
+declare continue handler for not found return 0;
+loop
+fetch group next row;
+insert into t2 (sal) values (x);
+end loop;
+end|
+show function code f1;
+Pos	Instruction
+0	hpush_jump 2 1 CONTINUE
+1	freturn int 0
+2	agg_cfetch
+3	stmt 5 "insert into t2 (sal) values (x)"
+4	jump 2
+5	hpop 1
+drop function f1;
diff --git a/mysql-test/main/sp-code.test b/mysql-test/main/sp-code.test
index 1f2f5191f0a..f8c1b4f0a92 100644
--- a/mysql-test/main/sp-code.test
+++ b/mysql-test/main/sp-code.test
@@ -927,3 +927,22 @@ $$
 DELIMITER ;$$
 SHOW PROCEDURE CODE p1;
 DROP PROCEDURE p1;
+
+--echo #
+--echo # MDEV-14623: Output of show function code does not show FETCH GROUP NEXT ROW
+--echo # for custom aggregates
+--echo #
+
+delimiter |;
+create aggregate function f1(x INT) returns int
+begin
+  declare continue handler for not found return 0;
+  loop
+    fetch group next row;
+    insert into t2 (sal) values (x);
+  end loop;
+end|
+
+delimiter ;|
+show function code f1;
+drop function f1;
diff --git a/sql/sp_head.cc b/sql/sp_head.cc
index 1514689d8b3..ac88f05a866 100644
--- a/sql/sp_head.cc
+++ b/sql/sp_head.cc
@@ -4409,7 +4409,7 @@ sp_instr_cfetch::print(String *str)
 int
 sp_instr_agg_cfetch::execute(THD *thd, uint *nextp)
 {
-  DBUG_ENTER("sp_instr_cfetch::execute");
+  DBUG_ENTER("sp_instr_agg_cfetch::execute");
   int res= 0;
   if (!thd->spcont->instr_ptr)
   {
@@ -4434,7 +4434,16 @@ sp_instr_agg_cfetch::execute(THD *thd, uint *nextp)
   DBUG_RETURN(res);
 }
 
+void
+sp_instr_agg_cfetch::print(String *str)
+{
 
+  uint rsrv= SP_INSTR_UINT_MAXLEN+11;
+
+  if (str->reserve(rsrv))
+    return;
+  str->qs_append(STRING_WITH_LEN("agg_cfetch"));
+}
 
 /*
   sp_instr_cursor_copy_struct class functions
diff --git a/sql/sp_head.h b/sql/sp_head.h
index f588f79b599..c0c0c83b77e 100644
--- a/sql/sp_head.h
+++ b/sql/sp_head.h
@@ -1957,7 +1957,7 @@ public:
 
   virtual int execute(THD *thd, uint *nextp);
 
-  virtual void print(String *str){};
+  virtual void print(String *str);
 }; // class sp_instr_agg_cfetch : public sp_instr