Bug#30875669 CORE CLIENT CANNOT SEND QUERY WITH NUMBER SIGN OR DOUBLE

DASH IN HINT COMMENT

Problem:
Server do not allow using '#' and '-- ' inside hint comment if preserve
comments is turned off.

Fix:
Allow using '#' and '-- ' inside hint comment irrespective of preserve
comments status because that is what is documented.

Change-Id: I976f98e2954d9bc7f007b4acd6627726416b72ba

Author: Samar Pratap Singh

client/mysql.cc

@@ -1,5 +1,5 @@
 /*
-   Copyright (c) 2000, 2023, Oracle and/or its affiliates.
+   Copyright (c) 2000, 2024, Oracle and/or its affiliates.
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License, version 2.0,
@@ -2679,8 +2679,8 @@ static bool add_line(String &buffer, char *line, size_t line_length,
       }
       buffer.length(0);
     }
-    else if (!*ml_comment && (!*in_string && (inchar == '#' ||
-                                              (inchar == '-' && pos[1] == '-' &&
+    else if (!*ml_comment && (!*in_string && ss_comment != SSC_HINT && (inchar == '#' ||
+        (inchar == '-' && pos[1] == '-' &&
                               /*
                                 The third byte is either whitespace or is the
                                 end of the line -- which would occur only

mysql-test/r/bug30875669.result

@@ -0,0 +1,7 @@
+# Bug#30875669 CORE CLIENT CANNOT SEND QUERY WITH NUMBER SIGN OR DOUBLE DASH IN HINT COMMENT
+CREATE USER myuser;
+id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	filtered	Extra
+1	SIMPLE	NULL	NULL	NULL	NULL	NULL	NULL	NULL	NULL	NULL	No tables used
+id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	filtered	Extra
+1	SIMPLE	NULL	NULL	NULL	NULL	NULL	NULL	NULL	NULL	NULL	No tables used
+DROP USER myuser;

mysql-test/t/bug30875669.test

@@ -0,0 +1,9 @@
+--echo # Bug#30875669 CORE CLIENT CANNOT SEND QUERY WITH NUMBER SIGN OR DOUBLE DASH IN HINT COMMENT
+
+CREATE USER myuser;
+
+--exec $MYSQL --user=myuser --skip-comments -e "explain select /*+ QB_NAME(`select#1`) */ 1;"
+
+--exec $MYSQL --user=myuser --skip-comments -e "explain select /*+ QB_NAME(`select-- `) */ 1;"
+
+DROP USER myuser;